Part 2 book “Clinical management of binocular vision heterophoric, accommodative, and eye movement disorders” has contents: Accommodative dysfunction, eye movement disorders , cyclovertical heterophoria, fixation disparity, refractive amblyopia, interactions between accommodation and vergence,… and other contents.
13 Eye Movement Disorders his chapter discusses the characteristics, diagnosis, and management of fixational, saccadic, and pursuit eye movement disorders We use the term ocular motor dysfunction to refer to the condition in which there are problems in all three areas of eye movement function In our experience, this is the most common clinical presentation It is unusual to find saccadic dysfunction in isolation of fixational or pursuit anomalies, or pursuit dysfunction in isolation of fixational or saccadic anomalies Eye movement disorders are a diagnostic and management concern of optometrists because of the effect such problems may have on the functional capability of an individual Unlike accommodative (1) and binocular vision skills (2), which reach adult levels of development very early in infancy, clinical assessment indicates that eye movement development is considerably slower, continuing through the early elementary school years (3,4) The clinical picture of slow development is not consistent with the basic research data that suggest the presence of normal eye movements by approximately age or years This apparent difference is likely to be related to cognitive and attentional factors affecting eye movements through about age 12 Because of the long developmental process for eye movement control, slow development can leave a child with inadequate skills to meet the demands of the classroom (5) Saccadic and pursuit dysfunction, therefore, primarily interfere with performance in schoolchildren, although some authors have reported the presence of these problems in adults as well (6,7) Much of the emphasis of both researchers and clinicians has been on the relationship between eye movements and reading During reading, the three important components of eye movements are saccades, fixations, and regressions Saccades take up approximately 10% of the reading time The average saccade is about to character spaces, which is about a 2-degree visual angle (8) The duration of the saccade is a function of the distance covered For instance, a 2-degree saccade takes about 25 to 30 milliseconds (ms), and a 5-degree saccade takes about 35 to 40 ms (8) Between saccades, the eye is relatively still in a fixational pause For normal readers, the average duration of the fixation is 200 to 250 ms An important characteristic of normal reading eye movements is the great variability both within and between subjects Saccade lengths can vary from to 18 character spaces, and fixation duration values can range from 100 to over 500 ms, for a single reader within a single passage (8) The third important characteristic of reading eye movements is the regression A regression is a right-to-left movement, and it occurs 10% to 20% of the time in skilled readers Regressions occur when the reader overshoots the target, misinterprets the text, or has difficulty understanding the text Because eye movement deficiencies intuitively seem to be so closely linked with reading, there have been numerous studies investigating this relationship Unfortunately, the results of these investigations are equivocal and, at times, confusing Limitations and differences in experimental design, methodology, statistical procedures, and assumptions among these studies have created difficulty in their interpretation (6) Two basic viewpoints have evolved about the relationship between eye movements and reading The first suggests that eye movement disorders can cause below-average reading ability (9–27) Investigators, using a variety of methods to assess eye movements, have found that poor readers tend to make more fixations and regressions than normal readers (10–20,27) The second view is that the random and unskilled eye movement skills observed in poor readers are secondary to deficient language skills that cause reading disorders Thus, the reading difficulty itself leads to erratic and inconsistent eye movements (26,28–32) A third perspective is probably most likely to be correct and is essentially a combination of the first two viewpoints This alternative (4) suggests that, in some cases, problems with fixation and saccadic abilities may be a primary factor interfering with a child’s ability to read quickly, comfortably, and with adequate comprehension In other cases, the eye movement deficiencies observed during reading may simply be a reflection of poor reading ability T 368 (c) 2015 Wolters Kluwer All Rights Reserved Chapter 13 / Eye Movement Disorders 369 Another important background issue is that during reading, eye movements are integrated with higher cognitive processes such as attention, memory, and the utilization of the perceived visual information (3,33–40) Some optometrists believe that there is a relationship between poor ocular motor skills and attentional problems (41) When such a relationship exists, treatment of eye movement disorders may lead to improvement in attention and concentration (38–41) There have been few studies of the prevalence of eye movement disorders, particularly in the population of normally achieving children and adults In children with reading and other learning difficulties, several studies have found a very high prevalence of eye movement anomalies (42–44) In a sample of 50 children between the ages of and 13 years with learning disabilities, Sherman (42) found that 96% had problems with ocular motor inefficiency (saccadic and pursuit problems) He did not state how eye movements were evaluated or his criteria for establishing a diagnosis of ocular motor inefficiency Hoffman (43) reported on a sample of 107 children between the ages of and 14 years with learning problems He evaluated pursuits and saccades using the qualitative scales described in Chapter along with an objective assessment using the Eye Trac The criteria for a diagnosis of ocular motor dysfunction were performance below a 3+ on the subjective clinical observation or years below age-expected values on the objective assessment His results revealed that 95% of the sample had ocular motor problems He also reported on the results of 25 children without learning problems and found that 24% had ocular motor problems It is interesting to note that both Hoffman and Sherman found that ocular motor dysfunction was the most prevalent vision disorder in their samples of learning disabled children Lieberman (44) studied the prevalence of vision disorders in 55 children between the ages of and 10 years at a school for children with emotional disorders He used observational scales and the New York State Optometric Association King-Devick test (NYSOA K-D) test to evaluate saccades The NYSOA K-D test is similar to the developmental eye movement (DEM) test described in Chapter Pursuits were evaluated using subjective observational scales; 53% of the children had saccadic dysfunction and 43% had pursuit anomalies In this same study, Lieberman reported that in a sample of 1,681 children in a normal population, the prevalence of saccadic dysfunction (using the NYSOA K-D test) was 22.6% Jainta and Kapoula (45) examined the relationship between saccades and vergence control during real text reading Thirteen dyslexic and seven non-dyslexic children read the French text “L’Allouette” in two viewing distances (40 cm vs 100 cm), while binocular eye movements were measured with an objective eye-tracking system They found that the binocular yoking of reading saccades was poor in dyslexic children (relative to non-dyslexics) resulting in vergence errors and fixation disparity The fixation disparity was larger for dyslexic children, making a larger demand on their sensory fusion processes The authors concluded that visual/ocular motor imperfections may exist in dyslexics that lead to fixation instability and thus, to instability of the letters or words during reading In our experience, and in the three studies described above (42–44), eye movement disorders are rarely present in isolation Rather, they are generally found associated with accommodative, binocular, and visual perceptual dysfunctions As a result, treatment of eye movement deficiencies generally occurs within the context of an overall treatment approach designed to deal with other problems as well It is clear that more investigation is needed into the prevalence of eye movement disorders to clarify their role in reading and other areas of function Regardless of these shortcomings in the literature, clinicians are regularly faced with children and adults presenting with signs and symptoms suggestive of fixation, saccadic, and pursuit disorders Psychologists and educators often refer children with concerns about poor tracking, skipping words and lines, and losing place when reading In addition, Solan (6) has demonstrated that there are adults with eye movement problems that interfere with their performance in school and at work Although these individuals often achieve at satisfactory levels, they complain of slow and inefficient reading (7) It is important for clinicians to be able to evaluate eye movement function and to prescribe appropriate treatment if a disorder is detected An important concept that must be emphasized is that optometrists treat eye movement disorders to normalize these functions and eliminate the patient’s symptoms We are not directly treating the reading disorders, although in some cases more accurate and efficient eye movements may lead to better reading performance Prognosis with Treatment The primary treatment approach for ocular motor dysfunction is vision therapy This suggests, of course, that eye movement function can be modified and improved through therapy Two very different approaches have been used to investigate whether eye movement function can be altered and improved with treatment (c) 2015 Wolters Kluwer All Rights Reserved 370 Section III / Management The plasticity and adaptability of the oculomotor system have been studied extensively by basic scientists This approach has uncovered a broad range of behaviorally induced adaptive responses and a strong potential for central nervous system plasticity within the vestibular-oculomotor system (46,47) Many of these studies have involved investigation aimed at identifying adaptive effects in human neuroophthalmologic disorders such as oculomotor paresis This line of investigation has generally found the presence of a daptive mechanisms that serve to offset degradation of ocular motor performance resulting from interference in n eural conduction, neuromuscular transmission, and muscle function due to such factors as aging, injury, and disease (46,47) One investigative approach that has been used to demonstrate that saccades can be modified involves the use of a paradigm called parametric adjustment This is an approach in which the subject’s saccades toward a target are made artificially inaccurate by shifting the target while the eye is already in flight (48) Using this approach, researchers have demonstrated substantial recalibration of saccadic amplitude after only a small number of saccades (48–51) Another basic science approach has been to study the changes that occur in ocular motility function after a paresis Kommerrell et al (52) studied the adaptability of the human saccadic system after the development of a sixth nerve paresis They found evidence that the central nervous system can readjust saccadic innervation and thereby improve performance Abel et al (53) performed a similar study with patients with third nerve palsies They were able to demonstrate that the adaptive readjustment of saccadic amplitude that occurs after a third nerve paresis depends on alteration of saccadic duration, not saccadic velocity These basic science studies have demonstrated ocular motor adaptation and plasticity, even in adult subjects The studies described above have found that saccadic function can be modified in both normal subjects and those with ocular motor disorders Clinical studies have also been performed to investigate the efficacy of treating ocular motor dysfunction Wold et al (54) reported on a sample of 100 patients who had completed a vision therapy program for a variety of problems, including accommodation, binocular vision, pursuits, and saccades Saccadic and pursuit functions were determined using subjective clinical performance scales such as those described in Chapter 1 Vision therapy consisted of three 1-hour visits per week The number of visits ranged from 22 to 53 It is important to understand that these patients did not only have eye movement disorders, but almost all patients had accommodative and binocular vision problems too Pretesting and posttesting revealed statistically significant changes in both saccadic and pursuit function In a study of 63 achieving high school students, Solan (55) found increased reading rate, fewer fixations, and fewer regressions after treatment A shortcoming of this study was that subjects received other forms of treatment along with vision therapy The subjects each received twelve 2-hour sessions of treatment consisting of work with a tachistoscope, a controlled reader, and vocabulary, skimming and scanning, and study skills Rounds, Manley, and Norris (56) used a Visagraph Eye-Movement Recording Systema to assess reading eye movements before and after vision therapy This investigation is one of the few to specifically study eye movement therapy alone They used a study population of 19 adults with reading problems and assigned 12 to the experimental group and to a control group The experimental group received weeks (12 hours) of exclusively oculomotor skill enhancement vision therapy The therapy consisted of three 20-minute office sessions and six 20-minute home sessions per week for weeks The control group received no intervention of any kind The experimental group trended toward improving reading eye movement efficiency (fewer regressions and number of fixations and increased span of recognition) compared to the control group Statistically significant differences, however, were not evident Young et al (57) also used an objective eye-movement recording instrument (Eye Trac) to assess reading eye movements before and after therapy The authors studied 13 schoolchildren who had failed a vision screening Each child had three 5-minute vision therapy sessions per day for weeks, receiving a total of 6 hours of eye movement vision therapy Testing after the therapy revealed a significant decrease in the number of fixations, an increase in reading speed, and a decrease in fixation duration Fujimoto, Christensen, and Griffin (58) investigated the potential for using vision therapy procedures prerecorded on videocassettes for eye movement vision therapy They had three groups of subjects The first group of nine subjects received standard eye movement vision therapy The second group received videocassette-based eye movement therapy, and the third group received no treatment The results showed that both standard eye movement vision therapy and videocassette-based therapy were equally effective in improving saccadic ability, whereas the control group showed no significant change Punnett and Steinhauer (59) also studied two different approaches for eye movement therapy They compared the effectiveness of vision therapy for eye movements using feedback versus no feedback They used the Eye Trac to monitor eye movements and studied nine subjects They found that the use of verbal feedback and reinforcement during vision therapy led to better treatment results (c) 2015 Wolters Kluwer All Rights Reserved Chapter 13 / Eye Movement Disorders 371 Solan, Feldman, and Tujak (7) provided vision therapy to improve the efficiency of reading eye movements in 20 older adults (aged 62 to 75 years) Subjects were divided into a training group and a control group The training group received 16 sessions of vision therapy over an 8-week period The control group did not receive any treatment for weeks After posttesting, of the 12 subjects in the control group were randomly selected to receive the 16 sessions of vision therapy The authors reported statistically and clinically significant improvement in all aspects of reading efficiency, including reduced number of fixations and regressions per 100 words, increased average span of recognition, and improved reading rate without loss of comprehension There were no gains in the control group The authors concluded that vision therapy to improve reading eye movement skills is appropriate at all age levels More recently, Solan et al (38) identified 31 sixth graders with reading comprehension scores about 1.5 to 3.5 years below grade level The Visagraph II was used to evaluate eye movements and obtain baseline data The 31 subjects were divided into two groups Half of the subjects received individualized reading comprehension therapy first, while the others received individual eye movement therapy for twelve 1-hour sessions After 12 sessions of treatment, reading comprehension and eye movements were reassessed The eye movement and reading comprehension treatment groups were reversed for the next 12 sessions After completion of 24 sessions, reading comprehension and eye movement ability were reevaluated They found significant improvements in the number of fixations, regressions, and rate of reading after the eye movement therapy This was true whether the eye movement therapy was done first or second In a subsequent study Solan et al (40) identified 30 children (mean age 11.3 years) with moderate reading disorders; 15 children received attention therapy, and 15 children were placed in a control group The treatment therapy group received twelve 1-hour sessions of individually monitored, computer-based attention therapy This attention therapy included five procedures commonly used in traditional vision therapy treatment: three programs from Computerized Perceptual Therapyb and two programs from the Perceptual Accuracy/Visual Efficiency (PAVE) Program.a Attention and reading scores improved significantly in the treatment group, whereas there were no significant improvements in reading scores after 12 weeks in the control group Other researchers have investigated the use of biofeedback to improve ocular motor ability in patients with nystagmus and eccentric fixation Goldrich (60) used a technique called emergent textual contour training to provide visual biofeedback regarding eye position and was successful in improving fixational ability Other investigators have used auditory biofeedback to treat nystagmus Ciuffreda, Goldrich, and Neary (70) and Abadi, Carden, and Simpson (61) achieved significant reduction in the amplitude and velocity of eye movements in congenital nystagmus Flom, Kirschen, and Bedell (62) were able to improve fixational skills in amblyopes with eccentric fixation using auditory biofeedback Fayos and Ciuffreda (63) studied the effectiveness of vision therapy for improvement of reading eye movements in adults They studied 12 young adult subjects (aged 18 to 38 years) using oculomotor auditory biofeedback training; 12 subjects read with auditory biofeedback during four half-hour training sessions over a 2-week period Their eye movements were recorded during the first and last sessions In addition, three control subjects followed the same protocol but did not receive any auditory feedback; 11 of the 12 subjects who received auditory feedback exhibited varying degrees of improvement in overall reading eye-movement efficiency (decreased number of fixations and regressions and increased reading rate) The training effect was most evident in subjects who initially read at a low-normal reading level on the Visagraph apparatus There was no consistent trend in the control subjects The authors concluded that oculomotor auditory biofeedback can be an effective training tool, particularly in low-normal readers The basic research and clinical studies reviewed demonstrate that eye movement skills can be modified in children and adults Additional research is necessary to study larger numbers of subjects and subjects who only have eye movement disorders It would also be important to clarify which vision therapy techniques are most efficacious Overview of General Management Principles for Ocular Motor Dysfunction The sequential management considerations for ocular motor dysfunction are Optical correction of ametropia Added lens power Vision therapy (c) 2015 Wolters Kluwer All Rights Reserved 372 Section III / Management Prescribing for any significant refractive error should be the first management consideration As discussed, it is unusual for eye movement problems to be present in isolation of other refractive, accommodative, or binocular vision disorders If these other conditions are present, it is important to also follow the guidelines recommended in Chapter with regard to correction of refractive error In the presence of uncorrected significant refractive error, fixational skills, saccades, and pursuits may be less than optimal Accurate fixation, saccades, and pursuits depend on adequate acuity The strategy of first prescribing for significant refractive error is therefore based on the assumption that there may be a cause-and-effect relationship between refractive error and eye movement anomalies If an eye movement disorder is present in isolation of other problems, vision therapy is the treatment of choice Prism and surgery have no role in the treatment of eye movement disorders, except for some patients with nystagmus (Chapter 18) Added lenses may be helpful if there is an associated accommodative or binocular problem Sohrab-Jam (64) studied the effect of added plus lenses on the eye movement skills of 38 elementary schoolchildren Book retinoscopy was used to determine whether an add would be appropriate The sample was then divided into one group that would benefit from added lenses (positive response group) and another that would not be expected to benefit (negative response group) The eye movements of the subjects were then tested using the Eye Trac instrument, first with no added lenses and then with a +0.50 add The results showed significant improvement in reading speed, fewer regressions, and higher relative efficiency with the +0.50 add in the positive response group In the negative response group, the use of added plus lenses actually caused a deterioration in eye movement skills This study underscores the value of prescribing added plus lenses if there is an associated accommodative or binocular vision problem along with the eye movement disorder It also suggests, however, that it is inappropriate to prescribe added plus lenses if the data not support such a prescription Vision therapy for eye movement skills generally involves more than mere treatment techniques for saccades and pursuits As a general rule, accommodative and binocular vision techniques are incorporated into the therapy program because eye movement anomalies are usually associated with accommodative, binocular, or visual perceptual disorders Even if the eye movement problem is present in isolation, there are two reasons for incorporating other techniques into the therapy program First, one objective of eye movement therapy is to improve fixational skills and attention All accommodative and binocular vision procedures require precise fixation and attention The second reason is that in everyday life, patients make saccadic and pursuit eye movements together with vergence changes and alteration of accommodative level It is therefore important to simulate natural seeing conditions in therapy by combining eye movements with changes in accommodative response and vergence eye movements Ocular Motor Dysfunction BACKGROUND INFORMATION Saccades are eye movements that enable us to rapidly redirect our line of sight so that the point of interest stimulates the fovea Saccades are the fastest eye movement, with velocities as high as 700 degrees per second (65) The saccadic peak velocity of normal observers is related to the size of the saccade This relationship, known as the main sequence, is so consistent between people that a 10% slower velocity is considered pathologic The normal latency for saccadic eye movements is about 200 ms, although the reaction time can vary depending on the luminance, size, and contrast of the target, motivation, and attention (65) The ideal saccade is a single eye movement that rapidly reaches and abruptly stops at the target of interest Saccades may be inaccurate, however, in two ways The most common inaccuracy is a slight undershoot In most cases, the saccade is slightly short of the target and the eye “glides” to alignment; in more extreme cases, however, a second, smaller saccade is made to reach the target A less common inaccuracy is an overshoot of the target As discussed, eye movements and, in particular, saccades have been a diagnostic and management concern of optometrists because of their importance in the act of reading Figure 13.1 is an illustration of the output from the Visagraph instrument described in Chapter The staircase-like plot displays the series of saccades and fixations that occur during reading Accurate saccades are important in almost any visual activity, including other aspects of school performance such as copying from the board or a book, sports, and many job-related activities Pursuit eye movements enable continuous clear vision of moving objects This visual following reflex ideally produces eye movements that ensure continuous foveal fixation of objects moving in space The maximum pursuit predictive velocities are approximately 60 degrees per second Smooth pursuit movements have a (c) 2015 Wolters Kluwer All Rights Reserved Chapter 13 / Eye Movement Disorders 373 n Figure 13.1 Output from a Visagraph instrument shorter average latency than saccades Their normal latency is about 130 ms (65) Pursuit movements are affected by age, attention, and motivation Because pursuit eye movements are only involved when a target is moving, they are more difficult to relate to reading and school performance than saccades Pursuits may play a more significant role in activities such as driving and sports CHARACTERISTICS Symptoms Most symptoms related to saccadic dysfunction (Table 13.1) are associated with reading These include head movement, frequent loss of place, omission of words, skipping lines, slow reading speed, and poor comprehension Another common symptom is a short attention span Teachers and parents often comment that children who not perform well in school not pay attention A child with inadequate fixation and saccadic ability may look away from the task more often than other children This “off-task” behavior may give the impression that the child is inattentive or impulsive Richman (33) was able to demonstrate that “off-task looking time” during a sustained visual attention test is significantly related to a classroom teacher’s observation of a child’s personal or social behavior Saccadic dysfunction may also lead to symptoms related to other school tasks, such as copying from the chalkboard, solving arithmetic problems with columns of numbers, and taking standardized psychological or educational tests with computer scan sheets (66) Although pursuit difficulties have been reported in children who have reading problems (67), pursuit dysfunction is probably more likely to interfere with activities such as sports Any sport that involves, for instance, following the flight of a ball will place significant demand on the pursuit eye movement system Symptoms such as trouble catching and hitting a baseball and difficulty with other sports involving timing and following a moving object may be related to pursuit dysfunction Signs Chapter described the three available methods for assessing saccadic ability: objective eye movement recording devices such as the Visagraph or the Readalyzer, standardized tests such as the DEM, and direct observations by the clinician using the Northeastern State University College of Optometry (NSUCO) oculomotor test Signs indicating saccadic difficulty include poor performance on one or more of these tests (Table 13.1) A score below the 15th percentile on the DEM (in either the ratio or error scores) or below age-expected-level performance on the NSUCO oculomotor test, the Visagraph, or the Readalyzer is suggestive of saccadic dysfunction Because saccadic eye movements are believed to play a significant role in reading, school performance, and the workplace, a great emphasis has been placed on diagnostic testing for saccades Fewer clinical assessment techniques are available for evaluating pursuit function The most common method, direct observation, is described in Chapter Another method that has been available for quite some time is the Groffman tracing procedure (68) This test is designed to evaluate pursuits in children A shortcoming of the procedure, however, is that there has been no study of its reliability and validity (c) 2015 Wolters Kluwer All Rights Reserved 374 TABLE 13.1 Section III / Management Symptoms and Signs of Ocular Motor Dysfunction Saccades Symptoms These symptoms are generally related to the use of the eyes for reading: Excessive head movement Frequent loss of place Omission of words Skipping lines Slow reading speed Poor comprehension Short attention span Difficulty copying from the chalkboard Difficulty solving arithmetic problems with columns of numbers Difficulty taking standardized psychological or educational tests with computer scan sheets Signs Below age-level performance on the Visagraph Score below 15% on the developmental eye movement test Score below age-expected norms on NSUCO oculomotor test Pursuits Symptoms Excessive head movement Poor performance in sports Reading difficulty Signs Score below age-expected norms on NSUCO oculomotor test NSUCO, Northeastern State University College of Optometry DIFFERENTIAL DIAGNOSIS The mild form of ocular motor dysfunction discussed here is a functional disorder with no significant underlying pathology It must always be differentiated, however, from other eye movement anomalies that may be related to more serious etiologies Saccadic and pursuit anomalies can be caused by abnormalities in the supranuclear control centers for these two functions and their connections to the extraocular muscles The saccadic and pursuit systems have separate and distinct neurologic pathways With the exception of saccades to visual stimuli, all saccades probably originate in the contralateral frontal eye fields (Brodmann area 8) (69) Stimulation from area 8, in the right frontal lobe, results in conjugate movement of the eyes to the left side The pathway is from the frontal eye fields to the conjugate gaze centers in the midbrain pons and then to the nuclei of the third, fourth, and sixth cranial nerves Saccades to visual stimuli are probably initiated in the general area of the occipitoparietal junction The control center for pursuit eye movements is believed to be the occipitoparietal junction (69) In contrast to saccadic control, supranuclear control of pursuits is ipsilateral The right occipitoparietal junction controls smooth pursuit to the right, and the left junction controls smooth pursuit to the left The pathway is from the occipitoparietal junction to the midbrain and to the nuclei of the extraocular muscles Because the pathways are distinct for saccades and pursuits, underlying neurologic disease can affect one system, leaving the other intact Thus, if a patient has abnormal pursuit movements with normal saccadic function, a problem in the occipitoparietal–supranuclear center should be suspected Conversely, an abnormality is likely in the frontal eye fields if pursuits are normal while saccades are abnormal Pathologic Causes of Saccadic Dysfunction Pathology of saccades can be divided into four categories: disorders of velocity, accuracy, initiation, and inappropriate saccades (Table 13.2) (65) Disorders of velocity include saccades that appear to be either too fast or too slow Saccades that appear too fast usually occur when the saccade is interrupted in midflight and its intended target is never reached These truncated saccades are common in myasthenia gravis Slow saccades are commonly associated with ocular motor nerve paresis or abnormalities in the medial longitudinal fasciculus (c) 2015 Wolters Kluwer All Rights Reserved Chapter 13 / Eye Movement Disorders TABLE 13.2 375 Differential Diagnosis of Saccadic Dysfunction Serious Underlying Disease to Rule Out Disorders of velocity Saccades that appear too slow Saccades that appear too fast Truncated saccades Possible Etiology Ocular motor nerve paresis Internuclear ophthalmoplegia Internuclear ophthalmoplegia Myasthenia gravis Disorders of accuracy Dysmetria Cerebellar disease Wallenberg syndrome Alzheimer disease Most basal ganglia degenerations Visual field defects Visual field defects Hypometria Hypermetria Disorders of initiation Congenital ocular motor apraxia Acquired ocular motor apraxia Inappropriate saccades Square wave jerks Macrosquare wave jerks Flutter Opsoclonus Parietal lesions Parkinson disease Cerebellar Cerebellar Cerebellar Cerebellar disease disease disease disease For instance, when a patient is requested to produce a saccade under binocular conditions to one side or the other, the adducting eye will either not follow or will lag behind in latency This is referred to as internuclear ophthalmoplegia and suggests a lesion in the medial longitudinal fasciculus in the brainstem Disorders of accuracy are referred to as dysmetria and can involve either undershooting (hypometria) or overshooting (hypermetria) the target Dysmetria is characterized by a series of small saccades necessary to attain fixation Clinically it appears as a to-and-fro saccadic oscillation around the fixation target before foveation is attained (69) It usually occurs at the end of a refixation It is the hallmark of cerebellar disease, but can also be caused by brainstem lesions, such as in the Wallenberg syndrome Hesitant long-latency hypometric saccades are common in Alzheimer disease and most basal ganglia degenerations Visual field defects can also cause both hypermetric and hypometric saccades to keep the target within an intact part of the visual field Disorders of saccadic initiation can vary from slight increases in saccadic reaction time, which are difficult to perceive clinically, to latencies greater than several seconds (70) In some conditions, there is a difference in saccadic performance between random saccades and voluntary saccades For instance, ocular motor apraxia is a condition in which a patient has nearly normal random saccades, but delayed initiation of voluntary saccades Ocular motor apraxia can be congenital or acquired When acquired, it is usually associated with parietal lesions Patients with Parkinson disease show a characteristic disorder of initiation When asked to make voluntary saccades between two targets, they undershoot, and the intersaccadic latencies gradually increase (71) The last category is inappropriate saccades Saccades are called inappropriate if they tend to interfere with foveal fixation A variety of conditions are included in this category: square wave jerks, macrosquare wave jerks, flutter, and opsoclonus Square wave and macrosquare wave jerks are relatively rare disorders and can be confused with nystagmus They are unwanted saccades that occur at random, and they interrupt fixation, followed by a corrective saccade to bring the eye back to the target There is usually a just-perceptible latency between the saccade away from and back to the target The disorder is called a square wave jerk when the amplitude is to degrees, and a macrosquare wave jerk when the movement is large (10 to 40 degrees) In either case, these eye movement disorders give the patient a shifty-eyed or noncooperative appearance because of the inability to sustain gaze with concentrated effort and are clearly abnormal (72) An ocular flutter is a burst of springlike decreasing horizontal oscillations that may either accompany small saccades or occur spontaneously during fixation (72) Cerebellar disease is usually the underlying cause of ocular flutter A more advanced form of ocular flutter is called opsoclonus or saccadomania, where the clinician (c) 2015 Wolters Kluwer All Rights Reserved 376 Section III / Management observes a more pronounced, almost constant, chaotic series of saccades in all directions This disorder is also generally caused by cerebellar disease and is easily recognized as abnormal Pathologic Causes of Pursuit Dysfunction Disorders of pursuits (Table 13.3) may be caused by lesions that involve the occipitoparietal junction, the pathways to the brainstem, and the brainstem itself The most common neurologic abnormality affecting pursuits is cogwheeling This refers to steplike eye movements that are used instead of smooth pursuits to follow an object This problem may be caused by basal ganglia disease, such as Parkinsonism or cerebellar disease It is also possible for cogwheeling to be asymmetrical, occurring, for instance, on rightward but not leftward pursuits Asymmetrical cogwheeling is also associated with nystagmus in primary gaze (69) The other common pursuit abnormality is low pursuit gain (eye velocity/target velocity) This disorder is commonly associated with aging or a variety of medications, particularly tranquilizers and anticonvulsants After medications, disease of the cerebellum or its brainstem connections is the most common cause of slow pursuit gain (69) In most cases, saccadic and pursuit disorders that have a serious underlying etiology can be readily differentiated from functional eye movement dysfunction Medically significant eye movement disorders are often dramatic in presentation, and the patient presents with a shifty-eyed or noncooperative appearance The history regarding onset and performance is important As you can see from Tables 13.2 and 13.3, patients presenting with these serious saccadic and pursuit disorders are often sick and present with other signs of neurologic disease It is always important to question the patient about use of medications, particularly the types listed in Table 13.4 Pursuits, in particular, are susceptible to a large variety of medications The history regarding onset will also be suggestive of a nonfunctional disorder Children with functional ocular motor dysfunction usually have a history of school-related problems—trouble with skipping lines, words, and loss of place—for several years A history of a child with strong academic performance in previous years and a sudden onset of tracking problems is more suspect TABLE 13.3 Differential Diagnosis of Pursuit Dysfunction Serious Underlying Disease to Rule Out Possible Causes Cogwheeling Basal ganglia disease Parkinsonism Cerebellar disease Aging Tranquilizers Anticonvulsants Slow pursuit gain TABLE 13.4 Drugs and Toxins that Affect Eye Movement Function Drug Possible Effects Diazepam Impaired saccadic velocity Impaired smooth pursuits Poor fixation Impaired smooth pursuits Poor fixation Impaired smooth pursuits Poor fixation Phenytoin Phenobarbital and other barbiturates Methadone Chloral hydrate Saccadic hypometria Impaired smooth pursuits Impaired smooth pursuits Poor fixation Impaired smooth pursuit Chlordecone, lithium, thallium Opsoclonus Alcohol and marijuana (c) 2015 Wolters Kluwer All Rights Reserved Chapter 13 / Eye Movement Disorders 377 TREATMENT As discussed, saccadic, pursuit, and fixational disorders generally occur together, and we use the term ocular motor dysfunction to refer to the condition in which problems are present in all three areas The treatment approach described is based on the assumption that problems are present in all areas If this is not the case with a particular patient, it is easy enough to leave out the inappropriate part of the treatment plan We recommend the management sequence listed on page 371 After correction of any significant refractive error and consideration of added lenses to manage an associated accommodative or binocular problem, the best treatment approach is vision therapy Vision Therapy A vision therapy program for ocular motor dysfunction generally requires from 12 to 24 in-office visits if vision therapy is office based If home vision therapy can be effectively administered, the total number of office visits can be reduced As stated in previous chapters, the key concept is that a given amount of vision therapy is necessary Whether it takes place in the office or at home is less important, as long as the therapy can be effectively administered The total number of therapy sessions also depends on the age of the patient and his or her motivation and compliance Specific Vision Therapy Program All the vision therapy techniques recommended here are described in detail in Chapters to Phase This first phase of therapy is designed to accomplish the objectives listed in Table 13.5 under Phase After establishing a working relationship with the patient, the primary goal of this first phase of therapy is to improve large or gross saccadic ability and small excursion pursuit ability It is important to note that the training progression is from large to small movements for saccades and from small to large excursions for pursuits (67,73) One of the important changes in vision therapy equipment has been the introduction of the computer Computers are ideally suited for creating the stimuli and variability necessary for vision therapy techniques This is particularly true for eye movement training Several excellent programs are available for this purpose The two primary systems available are the software from Computer Aided Vision Therapya and Computer Orthoptics,b both of which have many programs designed for saccadic or pursuit training TABLE 13.5 Objectives of Vision Therapy for Oculomotor Dysfunction Phase • Develop a working relationship with the patient • Develop an awareness of the various feedback mechanisms that will be used throughout therapy • Develop more accurate gross saccades and fine pursuits • Equalize gross saccadic and pursuit ability in the two eyes • Normalize positive fusional vergence (PFV) and negative fusional vergence (NFV) amplitudes (smooth or tonic vergence demand) • Normalize accommodative amplitude and ability to stimulate and relax accommodation Phase • Develop more accurate fine saccades and large excursion pursuits • Equalize fine saccadic and pursuit ability in both the eyes • Normalize PFV and NFV amplitudes (smooth or tonic vergence demand) • Normalize PFV and NFV facility (jump or phasic vergence demand) Phase • Integrate accurate saccades and pursuits with changes in vergence and accommodation • Develop ability to change from a convergence to a divergence demand (c) 2015 Wolters Kluwer All Rights Reserved 708 Index Bernell-N-Stein Bears cards, 177f, 178 Bernell-O-Scope stereoscope, 139f, 187f Bevel changes, in iseikonic lenses, 533, 533t Bifocal lenses, 97, 126 explanation of proposed treatment using, 677 flattop, 558 plus, 97, 126, 287 prescribing of, 287 BIM See Base-in prism Binocular accommodative facility (BAF) test, 3t, 3, 18, 19t, 20, 60, 73t, 121t for accommodative insufficiency, 339 with minus lenses, 60, 319 NFV tested by, 60, 279, 311, 548 PFV tested by, 58, 237, 311, 327 with plus lenses, 58, 327 red/green glasses used in, 218 Binocular accommodative facility (BAF) therapy in accommodative insufficiency vision therapy program, 344 Aperture Rule for, 217–218, 218f bar reader used in, 199, 200f description and setup of, 217–218, 217f endpoint of, 218 equipment needed for, 217 objectives of, 217 with variable tranaglyphs, 166 Binocular vergence interactions, 456–460 AC/A ratio in, 456–460, 458f–459f, 460t CA/C ratio in, 456–458, 457f Binocular vision fixation disparity analysis and, 5–9, 54, 120 nystagmus and, 498 testing for, 3–15, 3t, 4f, 5f, 6t, 8t, 14f, 19t, 19–22, 24 zone of singular, 463 Binocular vision disorders, 56–57 See also High AC/A conditions; Low AC/A conditions; Nonstrabismic binocular vision disorders; Normal AC/A conditions from ABI, 573–574 accommodative excess associated with, 350 accommodative insufficiency associated with, 340 asymptomatic, 318, 326 classification of, 56–57, 65–70, 65t, 73t, 103t, 113t–114t, 124, 129t, 292–293 primary care of, 112–120, 113t–114t, 124 treatment of, 92, 129t vertical, 70, 129t Binocular vision therapy accommodative therapy integrated with, 359, 372 computerized procedures for, 172 direction of difficulty stressed in, 154–156 factors to emphasize during, 175t NFV in, 155 office-based computer vision software for, 172–176, 174f, 175t PFV in, 155 specific guidelines for, 154–158 underlying concepts of, 152–154, 152f–154f Binocular vision–based model, for refractive error management, 616–618, 617f, 649 amblyopia and, 645 anisometropia and, 642–647 astigmatism and, 647–649 case studies of hyperopia treatment, 641–642 myopia treatment for patient with IXT, 643–644 myopia treatment incorporating atropine, 636–637 myopia treatment with atropine and contact lenses, 636–639 refractive treatment of hyperopia concurrent with treatment of anisometropic amblyopia, 645–646 successful myopia treatment, 634 treatment of myopia and astigmatism with RGP lenses, 648–649 unsuccessful myopia treatment, 635 clinical aspects of, 629 dual intersecting feedback loops in, 618f genetically programmed ocular growth, 623–625, 623f–624f, 625t, 629 hyperopia and, 641–642, 644–647 myopia and, 630 accommodation-vergence interactions, 632 amount and direction of peripheral retinal blur, 631–632 amount of lag, 631 amount of near work performed, 632 case studies of, 634–639, 643–644 normal visual acuity, 631 range of sensitivity to blur, 631–632 treatment of, 632–640, 633f ocular component growth in, 619–622, 621f–622f, 626 propositions of, 618f, 619, 622–623, 625–626, 640 rate of refractive change in, 626–628, 627f–628f refractive error distribution in, 619, 620f sequential management protocol for, 629 visually driven growth in, 625 Biocular loose lens rock description and setup of, 216 endpoint of, 216 equipment needed for, 216 Biofeedback auditory, 105, 140t, 144, 371, 510–511 in cyclovergence therapy, 425 therapy for ocular control, 510–511, 511f–513f Bioptograms, 188f Bitoric iseikonic lenses, 542 Blephamide SOP See Prednisolone/ sulfacetamide SOP Blur, 350–351, 351–352, 401–402 accommodation and, 616–618, 616f, 625 allowing of, 155 base-in to, 49, 50f base-out to, 49, 50f enhanced detection of, 640 feedback from, 145, 618 range of sensitivity to, 631 source of, 616, 616f–617f sustained retinal, 625 Boder Test of Reading-Spelling Patterns, 595 Book retinoscopy, 372 BOP See Base-out prism Brain injury See Acquired brain injury Brewster stereoscopes, 140t, 143 accommodative and convergence demands determined with, 188–189 convergence demand, 189 description and setup of, 187–188, 187f–188f endpoint of, 190 equipment needed for, 187 objectives of, 186 therapy procedures for, 190 Brock string, 140t, 142f, 381 description and setup of, 194, 195f endpoint of, 197 equipment needed for, 194 objectives of, 194 for physiologic diplopia, 142 task difficulty changed with, 197 therapy procedures for explanation of, 195–196 other types of, 196–19, 197f steps of, 195–196, 195f as voluntary convergence procedure, 194–197, 195f, 197f B-type case, 51 “Bug on string” procedure, 196 C CA/C ratios See Convergence accommodation to convergence ratios Calculated AC/A, 9–10, 119, 127–128, 127t, 459 Case analysis fixation disparity, 54 graphical accommodation-vergence interactions in, 451–452, 452f advantages of, 49 disadvantages of, 50–51 NPC in, 50, 50f sample worksheet of, 50, 50f Sheard’s criterion in, 51–52 integrative, 468 details of, 54–55 expected findings for optometric tests and, 55 optometric data grouping in, 55 steps of, 55, 85 normative, 50, 52, 429 accommodation-vergence interactions in, 452 advantages of, 53 disadvantages of, 54 expected findings in, 52, 53t three groups in, 52, 53t OEP analytical advantages of, 52 disadvantages of, 52, 55 expected findings of, 51, 51t requirements of, 51 primary entry points to, 76, 77f–78f, 133 prism in, 57–59, 62 of specific groups, 57–64 system used in, 72–85, 74f, 77f–79f, 83f, 85f decision-making process, 75f initial testing, 72–76, 74f, 75b phoria not present, 83–85, 85f sample cases, 79–84, 83f–84f significant phoria present at distance or near, 76–83, 77f–79f, 83f vision disorder classification and identification in, 57, 64–65, 65t Case history, 72, 75, 74f, 75b, 84, 87, 113t, 494 of accommodative insufficiency, 341 of deviation, 319, 328 importance of, 319, 343, 601 for learning-related vision disorders, 602, 603t–604t, 607f–609f Case presentation for child requiring vision therapy, 674–676 (c) 2015 Wolters Kluwer All Rights Reserved Index for conditions not requiring vision therapy, 677 importance of, 674 sequence of, 675t Case reports, 102, 102f Case typing, 51 CAVT See Computer Aided Vision Therapy Center of symmetry, 431, 431f, 433, 439 Central nervous system stimulants, 342t Central tranaglyph targets, 162f, 163 Central vestibular nystagmus, 499 Cerebellar disease, 389–390, 376t Cerebrovascular accident (CVA), 572 Cheiroscope, 140t, 420 diagnostic procedure for, 190, 191f interpretation and, 191–192, 191f Keystone Correct-Eye-Scope, 190, 191f in red-red rock therapy procedure, 210f therapy procedures for, 192, 192f Cheiroscopic tracings, 16 in divergence excess vision therapy, 302 drifting during, 191, 191f forms for, 191f interpretation of, 191–192, 191f scribbling during, 192, 192f short pencil strokes used during, 192, 192f suppression and, 192 Chiastopic fusion, 177, 183, 183f, 184 Children with accommodative dysfunction, 338 with astigmatism, 647–648 bifocal prescriptions for, 287 contact lenses worn by, 637–638 with convergence insufficiency, 674–677 with CUC, 547 developmental milestones of, 606t with divergence excess, 295, 495 with learning-related vision disorders, 594–597, 600–606 myopia development in, 620, 626, 627f–628f noncomputerized techniques for, problems with, 172 with nystagmus, children with, 491–492, 494–495, 503 with ocular motor dysfunction, 156, 376 “off-task looking time” of, 373 parallax and, 152 parents of, 605–606, 607f–609f, 686–688, 690–691 preschool, 295, 495 vision therapy for, 103, 148, 675–676 Chloral hydrate, 376t Chlordecone, 376t ChromaGen lenses, 620 Chromatic aberration error signal, 637–638 Chronic hyperinsulinemia, 640 Ciliary muscle, tonus of, 93 Ciliary spasm See Accommodative excess CISS See Convergence Insufficiency Symptom Survey CITT See Convergence Insufficiency Treatment Trial Classification system, of common vision problems accommodative, 56, 64–65, 65t, 70–71 alternative system of, 64, 65t binocular, 56–57, 65–70, 65t, 73t, 103t, 113t–114t, 124, 129t, 292–293 case analysis and, 57–59, 64–65, 65t Duane’s, 64, 124, 309, 335 ocular motor, 57, 63, 65t, 72, 73t vertical, 57, 62, 65t, 70 Clinical interview, 602 Clinically significant aniseikonia, 517 Clip-on aniseikonia correction, 521, 522t Cognitive testing, 601–602 Cogwheeling, 376, 376t College of Optometrists in Vision Development Quality of Life Outcomes Assessment (COVD-QOL), 91–92, 91f, 239 Colored circle cards for convergence, patient instructions for, 700–701 Colored filters effectiveness of, 598–599 reading and, 598–600 studies on, 598–600 Communication in case presentation, 674–677, 675t insurance letters, 683–684, 688–690 letters to parents, 686–688, 690–691 with other professionals, 678, 686–688 Complications, of refractive surgery, 657t case studies of accommodative spasm, 664–666 contact lens occluder to treat intractable diplopia, 669–670 decompensation of strabismus, 662–663 previous prism wear, 660–661 residual hyperopia causing decompensated esotropia, 659–660 surgically induced anisometropia, 661–662 surgically induced anisometropia causing aniseikonia, 657–659 surgically induced monovision causing diplopia, 663–664 vision therapy used to treat postrefractive surgery convergence insufficiency, 670–671 monovision accommodative issues, 664–666 convergence issues, 664–666 decompensation and, 662–663 diplopia caused by, 663–664 pre-Lasik trial and, 663 prevalence of, 655 risk stratification of, 667t sequential management considerations for, 668t added lenses, 669 occlusion, 669 optical correction of ametropia, 669 prism, 669 resistance and, 669 resistance to optical correction of ametropia, added lenses, and prism, 669 vision therapy, 670–671 surgery-associated aniseikonia, 656–659, 661–662 anisometropia, 656–659, 661–662 causes of, 657t esodeviation, 656 exodeviation, 656 fourth nerve weakness, 656 test battery for identification of, 666t Computer Aided Vision Therapy (CAVT) benefits of, 684 Computer Vergences program of, 175, 175t, 206, 231 description and setup of, 226–230 home use of, 175, 175t, 206 ocular motor dysfunction treated with, 377 Random Dot Stereograms in, 175, 206, 231 Track and Read program of, 228, 231 Wayne engineering, 228 Wayne membrane saccadic fixator, 229–230 (c) 2015 Wolters Kluwer All Rights Reserved 709 Computer home therapy procedures, 231, 206 advantages and disadvantages of, 679–680 for ocular motility, 231 Computer orthoptics, 231 home therapy system, 231 computer-aided vision therapy, track and read, 231 Computer Orthoptics VTS3 Liquid Crystal System accommodative program of, 211 benefits of, 684 description and setup of, 211 factors to emphasize with, 175, 175t Jump-Jump Vergence program, 175 multiple choice vergence program, 172–175, 174f ocular motor dysfunction treated with, 377–378 random dot stereopsis in, 174f, 175 Step-Jump Vergence program, 174 Computer Orthoptics VTS4 Liquid Crystal System, 172, 226 Computer software/Advanced technology procedures Computer Orthoptics Liquid Crystal Automated Vision Therapy (VTS4), 226–227 Computer Perceptual Therapy (CPT), 227 instrumentation, 684 neurovision rehabilitator (NVR), 228, 228f office-based, 172–176, 174f, 175t Sanet Vision Integrator (SVI), 227 Wayne membrane saccadic fixator, 229f–230f description and setup of, 230 equipment needed for, 230 objectives of, 229 Computer use complex (CUC), 547 binocular and accommodative data analysis and, 548 case studies of added lenses for near, 556–557 ergonomic issues, 564–566 medical treatment, 563–564 prism correction, 559–560 vision therapy, 561–562 children with, 547 clinical evaluation of accommodative ranges (NRA/PRA), 555 accommodative accuracy, 555 history and symptoms, 554 tests in, 555–556, 556f workstation, 554, 570 Computer Use Questionnaire for, 553, 559–560, 568–571 differential diagnosis of, 548, 549t etiology of, 547 NFV and, 548 prevalence of, 547 signs and symptoms of, 548, 549t, 566, 568–569 terminology of, 547 treatment of added lenses, 550, 556–557 ametropia correction, 550 best refractive correction, 556–558 computer monitors, 553 course and prognosis, 554 ergonomic issues, 551, 552f, 562, 564–566 key points of, 554 lens design issues in, 558–559, 558f 710 Index Computer use complex (CUC) (continued ) lighting conditions and glare, 551 ocular health, 551, 556 prism, 550, 559–560 refresh rate, changing of, 553 rest breaks, 553 seating position, 552 sequential management protocol for, 549–550, 550t, 556 surgery, 551 vision therapy, 551, 560–562 working distances and positions, 552 Computer Use Questionnaire, 553, 559–560, 568–571 Computer Vergences program, 175, 175t, 206, 231 Computer vision syndrome, 547–548 See also Computer use complex Computerized binocular therapy procedures advantages of, 173 programs for, 172 Computerized Perceptual Therapy, 371 Computerized tomography (CT) scans, 499 Conjugate prism, 507 Contact lenses, 481, 504 aniseikonia and, 529–530 children wearing, 637–638 intractable diplopia treated with, 669–670 myopia treated with, 638–639 occluder, 669–670 in pre-Lasik monovision trial, 663–664 reverse geometry, 638–639, 648–649 rigid gas-permeable, 504, 637–639, 648–649 soft, 637, 640, 647 Contour stereopsis, 17, 17f Convergence See also Near point of convergence amplitude of, 3t, Brewster stereoscope determining demands of, 188–189 colored circle cards for, 700–701 cyclophoria associated with, 400–401 decreased nystagmus with, 506 divergence alternated with, 250, 285 jump, 13, 240 spasm of, 280 training techniques of, 313 Convergence accommodation to convergence (CA/C) ratios, 57, 59, 292, 444, 453, 454f, 461–463, 467 AC/A ratios’ relationship with, 460, 616–617, 617f in binocular vergence interactions, 456–458, 457f lag of accommodation minimized through, 632–633, 633f significance of, 11 stimulus v response, 11 test for, 3t, 10–11, 57 Convergence excess, 78t–79t, 97t, 261 binocular and accommodative data analysis and, 279 case studies of, 80–82, 285–290, 286–290 classification of, 64 deviation characteristics of, 277 diagnostic findings summary for, 73t differential diagnosis of, 279–280, 280t hyperopia associated with, 278, 280–281 NFV and, 278 PFV and, 282t prevalence of, 277, 290 reading and, 664 refractive error and, 278 sequential management considerations of, 274t signs and symptoms of, 68–69, 277–279, 278t treatment of, 105 added plus lenses, 280–281, 281, 281t lenses, 280 pharmacologic, 278 prism, 281 surgery, 285 vision therapy, 281–285, 282t, 283t–284t Convergence insufficiency, 293 binocular and accommodative data analysis and, 240 case studies of, 241 convergence insufficiency and vertical deviation treated with prism and lenses, 582–584 convergence insufficiency complicated by right hemianopia, 584–586 convergence insufficiency complicated by visual processing defects, 586–588, 588t with hyperopia, 253–255 with presbyopia, 255–257 pseudoconvergence insufficiency, 257–258 with secondary accommodative excess, 251–253, 357 vision therapy used to treat postrefractive surgery convergence insufficiency, 670–671 children with, 674–677 classification of, 64 definite, 237 definition of, 237 deviation characteristics of, 240 diagnostic findings summary for, 73t differential diagnosis of, 241–242, 242t hyperopia associated with, 235–236, 235t, 243, 253–255 management of, 235–236, 235t myopia associated with, 235–236, 242 NFV and, 249–250 NPC and, 239 PFV and, 240–241 prevalence of, 237 pseudoconvergence insufficiency v., 241–242, 257–258, 339, 349 refractive error and, 239 symptoms and signs of, 65–66, 65t, 90–92, 90f, 237–240, 238t treatment of, 105 lenses, 242–243, 582–584 prism, 243–244, 582–584 surgery, 251 vision therapy, 244–251, 246t–250t, 670–671, 674–676 Convergence Insufficiency Symptom Survey (CISS), 90–92, 90f, 112, 115, 115f two-factor symptom analysis in, 238 validity of, 238 Convergence Insufficiency Treatment Trial (CITT), 90, 133, 244–246 Convergence paralysis, 242, 328t Convergence therapy in accommodative excess vision therapy program, 356 in accommodative infacility vision therapy program, 361 in accommodative insufficiency vision therapy program, 344 Aperture Rule with single aperture for, 177, 177f–178f, 180 for cyclovertical heterophoria, 424, 425f difficulty increased and decreased in, 167–168, 167t Eccentric Circles for, 182–183, 182f, 696–697 float and, 148 Free Space Fusion Cards A for, 182–183, 182f Free Space Fusion Cards B for, 185 Lifesaver cards for, 186 localization and, 148 planes of accommodation and vergence during, 152–154, 153f–154f, 178–180, 180f, 182–183, 182f Corneal curvature in aniseikonia, 519–520 RS related to, 621, 621f Corneal radius, 623, 623f–624f, 634 Corneal refractive therapy (CRT), 638 Cosmesis, 293 Counseling, patient, 415, 503–504 COVD-QOL See College of Optometrists in Vision Development Quality of Life Outcomes Assessment Cover test, 3, 3t, 5, 56, 73t in absence of strabismus, 5, 5f, 118 accommodation control for, 5, 118–119 alternate, 36, 522 objectivity of, 119 for phoria size and direction assessment, 5–7, 5f, 6t, 36–37, 63, 118 setup and administration of, 36–37 unilateral, 36 for vertical deviation assessment, 392 Critical period, of amblyopia, 473 Crossed eyes, 289, 325 Crowding phenomenon, 475–476 CRT See Corneal refractive therapy CT scans See Computerized tomography scans C-type case, 51 CUC See Computer use complex CVA See Cerebrovascular accident Cyclodeviations, 389 Cyclofixation disparity, 396 Cyclofusion, 400 Cyclopentolate hydrochloride, 93, 495 Cyclophoria convergence associated with, 400–401 definition of, 389 double Maddox prism evaluation of, 392, 393f double Maddox rod evaluation of, 392–393, 393f incidence of, 390, 390t symptomatic, 400–401 Cycloplegic refraction, 93, 252 Cycloplegic retinoscopy, 495 Cycloplegics, 342t Cyclovergence therapy biofeedback, 425 case study of, 424 dove prism, 425 indications for, 430 Maddox rod, 424–425 rotating cylinder, 424–425 stereoscope, 425, 425f Cyclovertical heterophoria case studies of cyclovergence therapy, 424, 425f latent hyperphoria, 408 recent-onset vertical diplopia, 399 secondary vertical deviation, 419 slab-off prism correction, 410–412 symptomatic cyclophoria, 400–401 vertical diplopia treated with sector occlusion and counseling, 416 vertical prism prescription, 414 (c) 2015 Wolters Kluwer All Rights Reserved Index vertical vergence therapy, 421–422 well-compensated vertical deviation, 421 causes of, 390 diagnostic testing of diagnostic occlusion, 397, 397t dissociated, 392–393, 393f, 393f, 395f fixation disparity, 393–395, 396f out of phoropter, 396–397 differential diagnosis of, 397–340 historical perspective of, 389 incidence of, 390, 390t, 574 motor and sensory fusion and, 391 signs and symptoms of, 391–392 terminology of, 389 treatment of convergence and accommodative facility procedures, 420 cyclovergence therapy, 423–425, 425f management considerations sequence for, 400t prism, 401–416, 401t, 405f, 407f refractive correction, 400–401 reluctance in, 389 stereoscope, 420 surgery, 425–426, 425 therapeutic occlusion, 416 vision therapy, 417–425, 418t, 423f, 425f Cyclovertical phoria, 83, 86f, 87 D Dartmouth Eye Institute, 517 Decompensated esodeviation, 656, 669 Decompensated exodeviation, 656 Decompensated fourth nerve weakness, 656 Definite convergence insufficiency, 237 DEM test See Developmental eye movement test Developmental eye movement (DEM) test, 25t, 27, 28f, 29–30, 56, 369, 687 Developmental milestones, 606t DFP ointment See Diisopropyl fluorophosphates ointment Diabetes, 342, 342t Diagnosis See also Diagnostic testing diagnostic evaluation, 117–118 history and symptoms, 112–117, 115f, 117f Diagnostic codes, 683 Diagnostic occlusion, 397, 397t, 521 Diagnostic testing See also specific tests accommodative disorders assessment, 18–23, 18t–19t, 22f–23f electrodiagnostic, 477 eye movement evaluation, 25–32, 25t–28t, 28f–29f, 31t for learning-related vision disorders defining problem in, 603, 603t family history in, 605, 605t–606t, 607f–609f infrared eye tracking in, 602 medical or developmental problems in, 605–606, 605t–606t parent questionnaire in, 605–606, 607f–609f previous testing for, 604, 604t nonstrabismic binocular vision disorders assessment, 3–15, 3t, 4f–5f, 6t, 8t, 117–118 refractive error determination, 2, 117–118 sensory status evaluation in, 3t, 4, 15–18, 16f–17f Diazepam, 376t Diet, myopia influenced by, 640 Diisopropyl fluorophosphate (DFP) ointment, 278 Diplopia, 436, 505t, 660 awareness of, 296–297 contact lenses for, 669–670 divergence excess and, 293, 296, 298 divergence insufficiency and, 260 feedback from, 145 fixation switch, 663–664 intractable, 669–670 pathologic, 296–297 physiologic, 142, 148–149 size comparison and, 522 surgically induced monovision causing, 663–664 vertical recent-onset, 399 sector occlusion and counseling treatment for, 416 Direct assessment of positive and negative fusional vergence, 119 Disparometer, 54, 396f, 432f, 433–434, 434 Dissociated phoria, 49, 50f Dissociated testing associated testing v., 453 cover, 392 Maddox double prism, 392, 393f Maddox rod, 392–393, 393f prism dissociation, 393, 395f three-step, 392, 393t Distance sphere modification, of forced vergence fixation disparity, 443–444, 445f Divergence convergence alternated with, 250, 285 localization and, 148–150, 148f, 152f Divergence excess background information about, 290 case studies of, 303–305 characteristics of, 291 children with, 295, 495 classification of, 64 cosmetic appearance of, 293 deviation characteristics of, 291 diagnostic findings summary for, 73t differential diagnosis of, 293–294 diplopia and, 293, 296, 298 forced vergence fixation disparity curve of, 445f NFV and, 298 PFV and, 292, 298 refractive error and, 293 sensory adaptations to, 293 sequential management considerations of, 274t signs and symptoms of, 69–70, 291–293, 291t simulated, 292, 294 treatment of added minus lenses, 295, 295t antisuppression therapy, 296–297 lenses, 294–295 prism, 295 surgery, 276, 294, 303 vision therapy, 276–277, 295–303, 297t, 299t–301t, 301f–302f true, 292, 294 Divergence insufficiency anisometropia present with, 236 background information about, 258 case studies of, 266–269 classification of, 64 clinical significance of, 269 comitancy and, 260 deviation characteristics of, 258–259 (c) 2015 Wolters Kluwer All Rights Reserved 711 diagnostic findings summary for, 73t differential diagnosis of, 260–262, 260t, 269 diplopia and, 260 divergence paralysis v., 260–262, 260t, 269 hyperopia present with, 236 management of, 236–237, 235t NFV, 260 refractive error and, 260 signs and symptoms of, 66, 258–260, 259t treatment of lenses, 262 prism, 236–237, 262 surgery, 266 vision therapy, 263–266, 263t–265t Divergence paralysis divergence insufficiency v., 261–262, 261t, 269 etiology of, 261 signs and symptoms of, 261, 261t Divergence therapy in accommodative excess vision therapy program, 356 in accommodative infacility vision therapy program, 361 in accommodative insufficiency vision therapy program, 344 Aperture Rule with double aperture for, 177, 177f, 180–181, 298, 301f difficulty increased and decreased in, 167–168, 167t distance in, 323–324 Eccentric Circles for, 182–183, 695–696 float and, 148 Free Space Fusion Cards A for, 182–183 Free Space Fusion Cards B for, 185 Lifesaver cards for, 186 localization and, 148–150, 152f Double Maddox rod, 392–393, 393f Double mirror stereoscope, 138, 139f Double vision, 325 Dove prism, 424 Duane’s classification, of vision disorders, 64, 124, 309, 335 Dynamic aniseikonia, 517, 529, 529 Dynamic reading, 231 Dyseidesia, 595t Dyslexia publicity of, 595 reading dysfunction v., 593, 594–595 tests for, 595 types of, 595, 595t Dyslexia Determination Test, 595 Dyslexia Screener, 595 Dysmetria, 375, 375t, 503t Dysnemkinesia, 595t Dysphonesia, 595t E Eccentric Circles, 140t, 182, 250–251 for convergence therapy, 182–183, 182f, 695–696 description and setup of, 182–184, 182f–183f for divergence therapy, 182–183, 695–696 endpoint of, 185 equipment needed for, 182 misconceptions about, 183 objectives of, 182 patient instructions for, 695–698 at 10–15 feet, 697–698 therapy procedures for, 184 two or more sets of, 184 Eccentric fixation, 371 712 Index Echothiophate iodide (Phospholine Iodide), 278 Educational history, to determine nature of learning problem, 603t Educational testing, 602 Educators, 613 Efferent infantile nystagmus, 501 Electrodiagnostic tests, 477 Electrophysiologic techniques classification of, 138, 140t instrumentation, 140, 143 types of, 140t, 143 Electroretinogram (ERG), 477 Emmetropia, 620, 623–624, 624t, 641, 643, 649, 649t Emotional testing, 602 Encephalitis, 342t, 343 Encyclophoria, 389 Entoptic phenomena classification of, 140 types of, 140t, 143 Epi-LASIK, 656 Equipment See Instrumentation ERG See Electroretinogram Eserine, 280 Esophoria, 50, 56, 57, 60, 63–64, 76, 93, 95t, 96, 97t, 98–100, 261, 460t See also Basic esophoria accommodative excess and, 350 computer-related vision problems and, 549t at distance, 67–69, 65t, 89 in fixation disparity analysis, 431 near, 127–128 Esotropia, 93, 259, 501–502, 659–660, 664 Estimated magnification prescriptions, 529 Evidence pyramid, 102, 102f Excyclophoria, 389 Excyclotorsion, 580 Exophoria, 49–50, 65t, 460t See also Basic exophoria accommodative excess and, 350 computer-related vision problems and, 549t at distance, 66–68, 69, 65t, 89 Exotropia, 277, 291, 580–581, 631, 643–644 Expenses, 682, 682t Eye movement disorders See also Ocular motor dysfunction from ABI, 574–575 functional capability influenced by, 368–369, 385 other disorders associated with, 369–371 prevalence of, 369 primary care of, 112–134, 113t–114t reading and, 368–369, 372–373, 381–383, 597, 598 treatment for, 104–106 Eye movement evaluation, 499 in diagnostic testing, 25–32, 25t–28t, 28f–29f, 31t fixation stability, 25–32, 25t–28t, 28f–29f, 31t important aspects of, 25, 25t pathological conditions in, 25t Eye tracking, 687 Eyestrain, 87 Eyewire distance changes, in iseikonic lenses, 532–533, 532t, 532f, 533t F Facial symmetry, 644 Fee slip, 683 Feedback See also Biofeedback from blur, 145, 618 from diplopia, 145 dual intersecting loops of, in binocular vision–based model for refractive error management, 618f from float, 148, 171 from kinesthetic awareness, 146, 171, 178 learning from, 172 from localization, 148–150, 148f, 150f–152f from luster, 146 from parallax, 152 patients receiving, 145 proportional-controller-based, 618 from SILO response, 146–148, 147f from suppression, 145 in vision therapy for convergence insufficiency, 247t Fees, 679, 681, 684 Fine motor developmental milestones, 606t First-degree targets See Superimposition targets Fixation disparity case analysis of, 54 definition of, 429 nonlinearities in, 467f phoria associated with, 431f, 432, 435 treatment of, 432, 444, 446f–447f, 447 vision therapy for, 432, 444, 446f as y-intercept, 432, 438 Fixation disparity analysis, 49, 54, 83, 86f, 120 See also Forced vergence fixation disparity curves advantages of, 54, 63–64 analysis approaches to, 429–430 associated phoria in, 431f, 431–432, 435 for cyclovertical heterophoria, 393–396, 395f disadvantages of, 54 esophoria in, 431 fusional vergence in, 430 horizontal prism in, 395, 404–406 Percival’s criterion and, 99–100 prism and, 99, 429–430 sensory factor in, 429 Sheard’s criterion and, 99 tests for, 56 accommodation-vergence interactions and, 464–466, 467f associated phoria v forced vergence fixation disparity assessment in, 9, 395, 406, 431 under binocular conditions, 5–9, 54, 120 equipment used in, 432f horizontal, 395 issues of, 120 technique for, 3, 3t, vertical, 395–397, 395f, 406 vertical relieving prism and, 100–101 x-intercept in, 431–432, 431f–432f, 431–432, 8, 438 y-intercept in, 432, 432, 438 Fixation misalignment See Fixation disparity Fixation stability evaluation, 56 pursuit in, 25t, 30–31, 31t, 48 saccades in, 25t–28t, 25–30, 28f–29f Fixation status test, 56, 63–64 Fixation switch diplopia, 663–664 Fixational pause, 368 Flashlight tag, 226 Flat fusion targets, 205–206, 205f–206f, 298, 301f, 701–702 Flattop bifocal lenses, 558 Flip lens test, 463 Flip lenses, 140t, 165–166, 165t, 463 Flip prism, 140t, 165, 165t procedures for, 176 tests with, 404, 405f, 461 Float, feedback from, 148 Flutter, 375t, 503t Focus, depth of, 128, 455, 455f, 462 Forced vergence fixation disparity curves, 396, 406, 407f associated phoria assessment v., 9, 395, 406, 431 clinical usefulness for prescribing, 439 lateral prism correction design, 439–442, 440f–441f vertical prism correction design, 442–443 of divergence excess, 445f generation of available instrumentation, 433–434, 434t horizontal fixation disparity curve, 435–437, 435f–437f with lens, 437, 438f phoropter setup, 434 vertical associated phoria, 435 graphing findings of, 437–438 interpretation of, 439 parameters of center of symmetry, 431, 431f, 433, 439 shape, 430–431, 430f slope, 430f, 430, 437–441, 437f, 438f, 440f–441f sphere modification in distance sphere modification, 443–444, 445f near addition determination, 443 vision therapy planning and monitoring, 444, 446f vertical fixation disparity analysis and, 9, 396, 405–406 Fourth nerve weakness, 656 Foveations, 492 Frame selection, 535 Free Space cards, 140t, 149, 151f, 250–251 Fusion Cards A for convergence therapy, 182–183, 182f description and setup of, 182–182 for divergence therapy, 182–183 endpoint of, 185 equipment needed for, 182 objectives of, 182 therapy procedures for, 184 two or more sets of, 184 Fusion Cards B for convergence therapy, 185 description and setup of, 185, 185f–186f for divergence therapy, 185 endpoint of, 186 equipment needed for, 185 objectives of, 185 therapy procedures for, 186 in modified Remy separator, 181, 181f Free space training, 138 Full refractive correction, 131, 132t, 481 Full Scale IQ score, 601 Functional amblyopia, unequal accommodation caused by, 338 Fused cross-cylinder test, 3, 3t, 19t, 24, 56, 62 ACC analysis with, 62 for accommodative insufficiency, 339 accommodative response assessed by, 19t, 24 NFV tested by, 60 PFV tested by, 60 (c) 2015 Wolters Kluwer All Rights Reserved Index Fusion chiastopic, 177, 183, 183f, 184 cyclo-, 400 horizontal, 391 orthopic, 177, 182–184 qualitative v quantitative aspects of, 313, 330 vertical, 62, 95, 391 Fusion enhancement therapy antisuppression, 508 horizontal vergence, 508–509 Fusional vergence See also Negative fusional vergence; Positive fusional vergence assessment of direct measures, 3–4, 3t, 8t, 11–12, 119 indirect measures, 3–4, 3t, 13–15, 318t, 319, 327t suppression and, 15–16 in fixation disparity analysis, 430 Fusional vergence dysfunction, 83, 86f background information about, 309–310 binocular and accommodative data analysis and, 311 case studies of, 84, 316–317 deviation characteristics of, 310 diagnostic findings summary for, 73t differential diagnosis of, 311, 312t dismissing of, 310 Duane’s classification not describing, 309 NFV and, 313 PFV and, 312–313 prevalence of, 310 refractive error and, 310 sequential management considerations of, 308t signs and symptoms of, 67, 310, 311t terminology of, 310 treatment of, 313t lenses, 312 prism, 312 surgery, 309, 316 vision therapy, 154, 312–316, 313t–315t Fusional vergence therapy, 154 anaglyphs, Polaroids, and liquid crystal filters, 160–176, 161f–163f, 164t–165t, 166f, 167t, 168f–171f, 174f, 175t lenses, prisms, and mirrors, 176 paper, pencil, and miscellaneous tasks, 182–186, 182f–183f, 185f–186f 192–196, 192f–193f, 196f septums and apertures, 187f–191f, 176–181, 177f–181f stereoscope, 186–194, 187f–188f, 190f–194f with voluntary convergence procedures, 194–197, 195f, 197f–198f G Gabapentin, 513 Ganglion blockers, 342t General skills case See Fusional vergence dysfunction Genetically programmed ocular growth heredity influencing, 624–625, 625t influence of, 629 relative strength of, 623–624, 623f–624f, 626 Genetics counseling for, 501 myopia influenced by, 623–625, 25t RS and, 618–619 Glasses See also Red/green glasses learning-related vision disorders and, 598–600 liquid crystal, 172–173 reading and, 341, 598–600 Global targets, 16, 16f Gradient AC/A, 9–10, 458–459 Graphical analysis accommodation-vergence interactions in, 451–452, 452f advantages of, 49 disadvantages of, 50–51 NPC in, 50, 50f sample worksheet of, 50, 50f Sheard’s criterion in, 51–52 Graphing, of forced vergence fixation disparity curves, 437–438 Groffman tracings, 31, 378 Gulden fixation sticks, 5, 5f, 36 H Habitual spectacle lenses, 408, 414 Haidinger brush, 140t, 144 Hand-held acuity test cards, 495, 496f Hand-held mirrors, 140t Haploscope, 140t Hart chart, 140t distance-to-near accommodative rock (monocular) description and setup of, 218, 219f endpoint of, 219 equipment needed for, 218 objectives of, 219 for saccadic therapy, 702–703 description and setup of, 222 equipment needed for, 222 objectives of, 222 patient instructions for, 703–704 Hawthorne effect, 337 Hemianopia, 584–586 Heredity, genetically programmed ocular growth influenced by, 624–625, 625t Hering-Bielschowsky afterimage test, 293 Heterophoria, 63, 89, 98 See also Cyclovertical heterophoria AC/A ratio and, 56–57, 64, 124, 234–236, 273–277, 460t analysis of, 124 horizontal, 64 magnitude of, 402 occlusion and, 101 space eikonometer and, 525, 526f vertical, 57, 64, 124, 392, 393f, 401t High AC/A conditions, 68–70, 73t, 103t, 113t–114t, 124, 129t, 279, 292, 460t See also Convergence excess; Divergence excess added lenses and, 273–276 general management principles for, 274–276, 274t, 305 treatment of, 276–277 Hofstetter’s formula, 20, 337 Home Therapy System (HTS), 206, 231, 250–251 ADRiNet Dynamic Reader and, 231 effectiveness of, 244 Home-based vision therapy, 133, 172 for accommodative excess, 354t–356t, 356 for accommodative infacility, 361, 363t for accommodative insufficiency, 344, 344t–345t accommodative therapy with, 219–220 for basic esophoria, 322t–323t, 323 for basic exophoria, 331t–332t, 332 (c) 2015 Wolters Kluwer All Rights Reserved 713 computer home therapy procedures in, 175, 175t, 206, 228, 231, 679–680 for convergence excess, 283t–284t for convergence insufficiency, 251, 248t–250t for cyclovertical heterophoria, 420 for divergence excess, 299t–301t, 303 for divergence insufficiency, 262t–265t effectiveness of, 244–246 for fusional vergence dysfunction, 314t–315t, 315 HTS, 206, 231, 250–251 in-office therapy v., 679–680 modified Remy separator for, 181 for ocular motor dysfunction, 378t–380t patient instructions for Ann Arbor letter tracking, 703 beads and string, 699–700 colored circle cards for convergence, 700–701 Eccentric Circles at 10–15 feet, 697–698 Eccentric Circles for convergence, 696–697 Eccentric Circles for divergence, 695–696 first- or second-degree targets at 10–15 feet, 701–702 Hart chart for saccadic therapy, 702–703 monocular loose lens rock, 704 red lens and penlight technique to eliminate suppression, 694 tranaglyph slides, 698–699 TV trainer, 694–695 visual tracing, 703–704 PPT, 244–246 Horizontal fixation disparity curve examples of, 435–436, 436f, 437f measurement of, 435–436, 436f modified curve generation and, 436–437, 437f Horizontal fusion, 391 Horizontal prism, 236, 281, 295 basic esophoria treated with, 320 basic exophoria treated with, 329 description of, 97–100, 103t, 128–130 in fixation disparity analysis, 393, 405–406 Horizontal rectus tenotomy, 514 Horizontal vergence therapy, 417–418 cyclovertical heterophoria treated with, 417–418, 418t fusion enhancement with, 508–509 nystagmus treated with, 508–509 vertical vergence therapy v., 417–418, 418t Horror fusionis, 573 HTS See Home Therapy System Hyperopia, 92, 92t, 133, 616 accommodative esotropia secondary to, 664 accommodative fatigue secondary to, 335 amblyopia and, 474 basic esophoria associated with, 318 basic exophoria associated with, 328 in binocular vision–based model for refractive error management, 641–642, 644 convergence excess associated with, 278, 280–281 convergence insufficiency associated with, 235–236, 235t, 243, 253–255 divergence insufficiency present with, 236 latent, 83, 86f rate of refractive change in, 626, 627f residual, causing decompensated esotropia, 659–660 treatment of, 641–642 714 Index Hyperopic anisometropia, 644–645 Hyperphoria, 57, 64, 65t, 385 definition of, 389 incidence of, 390 latent, 407–408 Hypometra, 389, 375t I Ill-sustained accommodation, 57, 65, 65t, 71, 73t, 124, 336 case study of, 347–348 description of, 338 diagnostic findings summary for, 73t difficulty diagnosing, 348 signs and symptoms of, 71 Inappropriate saccades, 374, 375t Inefficient binocular vision See Fusional vergence dysfunction Infantile nystagmus, 491–492, 499–501 afferent v efferent, 501 astigmatism associated with, 504 characteristics of, 500t genetic counseling for, 501 jerk nystagmus in, 501, 501f Infravergence test, 56, 62 Initiation disorders, of saccades, 374, 375t Instrument training See Stereoscopes Instrumentation afterimages, 140, 140t, 143, 230–231 anaglyphs, 140, 140t apertures, 138, 139f, 140t, 141 basic, 684 categorization of, 138–144, 140t computer software, 684 electrophysiologic techniques, 140, 143 entopic phenomena, 140, 143 for forced vergence fixation disparity curves generation, 433–434, 434t lenses, 138–141, 140t for paper, pencil, and miscellaneous tasks, 140, 140t, 141–142, 142f for phoria measurement, 433–434, 443t Polaroids, 140t, 141 septums, 138, 140t, 141, 142f stereoscopes, 138, 139f, 140t, 143 Insurance coverage, 691–692 appeal letters for, 683–684, 689–690 basic issues of, 683 diagnostic codes for, 683 payment systems of, 683–684 predetermination letters for, 688–689 problems with, 682 Integrative analysis, 468 details of, 54–55 expected findings for optometric tests and, 55 optometric data grouping in, 55 steps of, 55, 85 Intelligence Quotient (IQ) test, 601–602, 604 Interagency Committee on Learning Disabilities, 594 Intermittent exotropia (IXT), 277, 291, 580–581, 631, 643–644 Intermittent photic stimulation, 512 Internuclear opthalmoplegia, 375, 375t Interpupillary distance (IPD), 434 Interview, clinical, 602 Intractable diplopia, 669–670 Intuitive colorimeter, 599 IPD See Interpupillary distance IQ test See Intelligence Quotient test Irlen filters, 599 Iseikonic lenses, 525 antireflective coating, 535 bitoric, 542 design examples of, 539–542 inadvertent corrections frame eye size changes, 543–544, 544f, 544t refractive index changes, 545 lens edge coating, 535 magnification by changing base curve, 533, 533t magnification by changing eyewire distance and bevel, 532–533, 532t, 532f, 533t magnification by changing lens thickness, 535, 536t–537t prescription considerations for, 535, 539t recommendations for, 529–542, 545 Isoametropic amblyopia, 472–473 case study of, 478 etiology of, 472 prevalence of, 473 sequential management protocol for, 478 suppression and, 475 IXT See Intermittent exotropia J Jackson cross-cylinder (JCC) testing, 2, 118 Jerk nystagmus, 493, 493f, 497, 501, 501f, 505t Jump convergence, 13, 240 Jump vergence training See Phasic vergence training Jump vertical vergence therapy, 422 Jump-Jump Vergence program, 175 K Keystone cards, 188f Keystone Correct-Eye-Scope, 190–191, 191f Kinesthetic awareness, feedback from, 146, 171, 175 King-Devick test See New York State Optometric Association KingDevick test Knapp’s law, 94, 518 L Lag, accommodation, 128, 455, 455f, 462, 468, 631–632, 633f Language milestones, 606t Lasek See Laser-assisted subepithelial keratectomy Laser in situ keratomileusis (Lasik), 655–660, 662–663 Laser-assisted subepithelial keratectomy (Lasek), 656 Lasik See Laser in situ keratomileusis Latent hyperopia, 83, 86f, 407–410 Latent hyperphoria, 407–408 case study of, 408 prism prescriptions for, 407–408 Latent nystagmus, 500t, 501, 508–509 Late-onset myopia, 620, 626, 627f Lateral associated phoria, 432 Lateral prism correction design, 439–442, 440f–441f Learning-related vision disorders See also Reading dysfunction case history for, 602, 603t–604t, 607f–609f case studies of therapy directly improving reading performance, 609–610 therapy unlikely to directly improve reading performance, 611–612 children with, 594–597, 600–606 classroom accommodations for, 613 colored filters and, 598–600 comanagement of, 594, 613 definition of, 594 diagnostic testing for defining problem in, 603, 603t family history in, 605, 605t–606t, 607f–609f infrared eye tracking in, 602 medical or developmental problems in, 605–606, 605t–606t parent questionnaire in, 605–606, 607f–609f previous testing for, 604, 604t epidemiology of, 594 glasses and, 598–600 language disorders, 604 optometrist’s role in management of, 593–594, 606, 613 research on, 597–598 signs and symptoms of, 597t three-component model of vision and, 594, 594t treatment of challenges in, 613 educational intervention v., 606 educators and, 613 objectives of, 606–613 other professionals and, 613 sequential treatment approach to, 613 vision therapy, 606, 608 visual efficiency disorders, 603–604, 606–613, 687–688 visual information processing disorders, 603–604 Lens edge coating, 535 Lens flipper testing, 463 Lens sorting (monocular) description and setup of, 212 difficulty level changed in, 214 endpoint of, 214 equipment needed for, 212, 213f–214f important factors in, 214 objectives of, 212 Lenses See also Added lenses; Contact lenses; Iseikonic lenses accommodation-vergence interactions treated with, 467 accommodative excess treated with, 353–354 accommodative infacility treated with, 359–362 accommodative insufficiency treated with, 343 accommodative therapy with, 212–218, 213f, 215f, 217f–218f advantages of, 141 basic esophoria treated with, 320 basic exophoria treated with, 328 bifocal, 97, 126, 287, 558, 677 categorization, 140, 140t ChromaGen, 620 coatings of, 535–536, 559 convergence excess treated with, 280 convergence insufficiency treated with, 242–243, 582–584 disadvantages of, 141 divergence excess treated with, 294–295 divergence insufficiency treated with, 262 fixation disparity curves generated with, 437, 438f (c) 2015 Wolters Kluwer All Rights Reserved Index flip, 140t, 165–166, 165t, 463 forced vergence fixation disparity curves generated with, 437, 438f fusional vergence dysfunction treated with, 312 fusional vergence therapy with, 176 habitual spectacle, 408, 414 instrumentation, 140, 140t loose, 140t, 165, 165t ocular motility procedures with, 221 phakic IOL, 656 procedures for, 176 rate of refractive change influenced by, 626 sag of, 543–544, 544f, 544t SILO response associated with, 147 TV trainer and, 202 vision therapy prescribed after, 328 Letter tracking, 140t Ann Arbor, 703 description and setup of, 222–224, 223f endpoint of, 224 equipment needed for, 222 objectives of, 222 Letters See Written correspondence Lid-suture myopia, 619 Lifesaver cards, 140t, 151f for convergence therapy, 186 description and setup of, 185, 185f–186f for divergence therapy, 186 endpoint of, 186 equipment needed for, 185 in modified Remy separator, 180, 181f objectives of, 185 therapy procedures for, 186 Liquid crystal filters, 172–175 See also Computer Orthoptics VTS3 Liquid Crystal System accommodative therapy with, 209–212, 210f, 211t fusional vergence therapy with, 160–176, 161f–163f, 164t–165t, 166f, 167t, 168f–171f, 174f, 175t Liquid crystal glasses, 172–173 Lithium, 376t Local stereopsis See Contour stereopsis Localization Aperture Rule and, 178, 178f convergence and, 148–149 divergence and, 149–150, 150f feedback from, 148–151, 148f, 150f–152f patients’ cues for, 148–151 Loose lens rock See Biocular loose lens rock; Monocular loose lens rock Loose lenses, 140t, 165–166, 165t Loose prism, 140t, 165, 165t, 176, 221 Loose prism jumps, 221 Low AC/A conditions, 56, 65t, 73t, 95–97, 103t, 113t–114t, 124, 129t, 240, 260, 460t See also Convergence insufficiency; Divergence insufficiency case studies of, 234–236 general management principles for, 234–236, 235 treatment of, 237 Low refractive error, 94 Luster, feedback from, 146 M M pathway See Magnocellular pathway MA See Meter angle Macrosquare wave jerk, 375, 375t Maddox double prism, 392, 393f Maddox rod for aniseikonia, 523 cyclophoria evaluated with, 392–393, 394f cyclovergence therapy with, 424–425 dissociated testing with, 392–393, 393f single v double, 392–393, 393f, 394f for vertical heterophoria, 392, 393f MAF test See Monocular accommodative facility test Magnetic resonance imagery (MRI), 499, 501 Magnocellular (M) pathway, 599 MAIT See Motor Alignment and Interaction Tests Malaria, 352, 342t Mallett unit, 16, 54, 131, 395, 396f, 432f Marijuana, 342t, 376t Marsden ball, 152f Maximum-plus refraction technique, 118 Maxwell spot, 140t, 144 Meares-Irlen syndrome, 598–600 Measured aniseikonia prescriptions, 529 Medial rectus weakness, 328t Medicare, 683 MEM retinoscopy See Monocular estimation method retinoscopy Memantine, 513 Meta-analysis, 102, 102f Meter angle (MA), 457f Methadone, 376t Minification, 20 Minus lens amplitude test, 18t, 20–22, 45–46 Minus lenses AC/A ratio measured by, 458 accommodative insufficiency treated with, 343 amblyopia treated with, 481 BAF test with, 60, 319 bevel changes in, 533, 533t at distance, 295 divergence excess treated with, 295, 295t MAF test with, 61 nystagmus treated with, 506 plane of accommodation influenced by, 153f PRA tests with, 319 prescribing of, 95–97, 95t–97t, 126, 128 retinal images minified by, 147 Mirror superimposition description and setup of, 205 endpoint of, 206 equipment needed for, 205 objectives of, 205 targets used in, 205, 205f–206f therapy procedures for, 205–206, 205f–206f Mirrors accommodative therapy with, 176, 212–218, 213f–215f, 217f–218f advantages of, 141 categorization of, 138–140 disadvantages of, 141 fusional vergence therapy with, 176 hand-held, 140t ocular motility procedures with, 221 Modified Remy separator description and setup of, 180–181, 181 equipment needed for, 180 in home-based vision therapy, 181 objectives of, 180 therapy procedures for, 181 Modified Thorington test accommodation control for, 7–8 phoria assessed by, 3, 3t, 7–8, 8t, 38–40, 63 Monocular accommodative facility (MAF) test, 18, 19t, 21, 56, 73t, 240 (c) 2015 Wolters Kluwer All Rights Reserved 715 for accommodative infacility, 358–359 for accommodative insufficiency, 339 accommodative system tested by, 61 fusional vergence dysfunction and, 311 with plus and minus lenses, 61 Monocular estimation method (MEM) retinoscopy, 3t, 3, 18, 47, 55, 73t, 121, 121t, 123t, 128 for accommodative insufficiency, 339 accommodative response assessed by, 18t, 19t, 23–24, 24f, 121, 121t, 455, 555, 555f accommodative system tested by, 61, 122 cards used for, 23, 24f issues of, 122 NFV tested by, 58, 279, 327, 548 for nystagmus, 497 PFV tested by, 58–59, 240–241, 339 Monocular loose lens rock, 214 description and setup of, 215, 215f endpoint of, 215 equipment needed for, 215 patient instructions for, 704 Monocular suppression, 527 Monovision accommodative issues, 664–666 convergence issues, 664–666 decompensation and, 662–663 diplopia caused by, 663–664 pre-Lasik trial and, 663 Monthly fee, 684 Morgan’s system of clinical analysis See Normative analysis Motor alignment analysis of, 63–64 nystagmus and, 498–499 Motor Alignment and Interaction Tests (MAIT), 56 Motor milestones, 606t Moving text dynamic reading, 231 MRI See Magnetic resonance imagery Multiple choice vergence program, 173–175, 174f Multiple sclerosis, 342t, 343 Myasthenia gravis, 374, 375t Myopia, 92t, 616 accommodative spasm and, 664–666 amblyopia and, 474–475 anisometropia and development of, 642–643 facial symmetry and, 644 head position and, 643 suppression of one eye in, 643 basic exophoria associated with, 328 in binocular vision–based model for refractive error management accommodation-vergence interactions, 632 amount and direction of peripheral retinal blur, 631–632 amount of lag, 631 amount of near work performed, 632 case studies of, 634–639, 643–644 normal visual acuity, 631 range of sensitivity to blur, 631–632 treatment of, 632–640, 633f children developing, 620, 626, 627f–628f convergence insufficiency associated with, 235–236, 242 genetics influencing, 624–625, 625t late-onset, 620, 626, 627f lid-suture, 619 overcorrection of, 625 rate of refractive change in, 626, 627f 716 Index Myopia (continued ) risk factors for, 632–640 treatment of contact lenses, 637–640 diet, 640 enhanced blur-detection ability, 640 IXT and, 643–644 pharmacologic, 636–637 reduced amount of near work, 640 successful, 634 undercorrection, 640 unsuccessful, 635 unilateral high, 473 N National Institutes of Health (NIH), 594 Near AC/A, 127–128, 127t Near addition power, 126, 128, 443, 633 Near astigmatic axis shift, 390t Near Mallett unit, 16 Near point of convergence (NPC), 55, 73t basic exophoria and, 326 convergence insufficiency and, 239 in graphical analysis, 50, 50f refractive error and, 326 tests for, 3t, 6, 8t, 13–14, 15, 43 accommodation-vergence interactions and, 461 important issues in, 120 PFV tested by, 58–59 recovery point in, 239 repetition of, 239 Negative fusional vergence (NFV), 55, 96, 462 accommodative insufficiency and, 340 in accommodative therapy, 155 analysis of, 69–60, 76, 78f, 80, 83f basic esophoria and, 309, 318, 318t, 321 basic exophoria and, 330 in binocular vision therapy, 155 computer-related vision problems and, 548 convergence excess and, 278 convergence insufficiency and, 239 CUC and, 548 divergence excess and, 298 divergence insufficiency and, 260 fusional vergence dysfunction and, 313 normalization of, 321, 380 ocular motor dysfunction and, 380 tests for BAF, 60, 279, 311, 327, 548 direct, 318t, 319, 327t at distance, 318t, 327t fused cross-cylinder, 60 indirect, 3–5, 3t, 13–15, 318t, 319, 327t MEM retinoscopy, 58, 279, 327, 548 at near, 318t, 327t PRA, 59–60, 279, 319, 548 smooth vergence, 59 step vergence, 59 vergence facility, 59 Negative relative accommodation (NRA) testing, 3–4, 3t, 19t, 42–43, 49, 50f, 55, 59–60, 73t for CUC, 555 PFV tested by, 58, 240, 311, 327 plus lenses with, 327 Neurologic testing, 604t Neurosurgery, 385 New Aniseikonia Test, 524, 524f New York State Optometric Association King-Devick (NYSOA K-D) test, 27, 369 Newcastle control score, NFV See Negative fusional vergence NIH See National Institutes of Health Nonfunctional etiology, testing to rule out, 72–76, 74f, 75b, 75 Nonstrabismic binocular vision disorders amblyopia and, 236, 275 anisometropia and aniseikonia managed in, 94–95 assessment of, in primary care optometry, 118–120, 124 common, analysis of, 124 diagnostic testing of, 3–15, 3t, 4f, 5f, 6t, 8t, 117–118 direct assessment of positive and negative fusional vergence in, 8t, 11–12, 119 fixation disparity assessment in, 5–7, general considerations in, 3–5, 3t, 4f, 118 indirect assessment of positive and negative fusional vergence in, 13–15, 120 phoria size and direction assessment in, 3t, 5–11, 5f, 6t, 120 sequential management considerations for, 235t Nonvariable tranaglyphs description and setup of, 170–171, 171f equipment needed for, 170 objectives of, 170 therapy procedures with, 171 Normal AC/A conditions, 65t, 67–68, 73t, 100, 100t, 103t, 113t–114t, 129t, 292, 311, 319, 327, 460t See also Basic esophoria; Basic exophoria; Fusional vergence dysfunction added lenses and, 307 differences among, 307 general management principles for, 307–309, 308t treatment of, 307–309 key points, 309 sequential considerations, 308t vertical deviations and, 307 Normative analysis, 50, 52, 429 accommodation-vergence interactions in, 452 advantages of, 53 disadvantages of, 54 expected findings in, 52, 53t three groups in, 52, 53t Nott retinoscopy, 18 NRA See Negative relative accommodation NSUCO oculomotor test, 25t, 26, 26t–27t, 30, 31t, 47–48, 63 Null region, 501 NYSOA K-D test See New York State Optometric Association KingDevick test Nystagmus, 371–372, 375 accommodation and, 497–498 blockage syndrome, 501–502, 514 case studies of biofeedback therapy, 509–510 conjugate prism, 507 high plus addition for near, 506 intermittent photic stimulation, 512 manifest latent nystagmus, 508–509 vertical line counting, 511–512 causes of, 494–495 characteristics of, 492–494, 492t, 493f children with, 491–492, 494–495, 503 clinical evaluation of, 494 binocular vision, 497–498 ocular health, 498–499 ocular motility, 296, 498–499 patient history, 494–495 refractive error, 495 systemic health, 498–499 visual acuity, 495–497, 496f conditions mimicking, 503t decreased, with convergence, 506 definition of, 491 differential diagnosis of, 499–503, 500t, 501f, 503t difficulty diagnosing, 491, 514 etiology of, 491 genetic counseling for, 503–503 infantile, 491–492, 499–501, 500t, 501f, 504 jerk, 493, 493f, 497, 501, 501f, 505t latent, 501, 500t, 501, 508–509 motor alignment and, 498–499 OKN, 498–499 pendular, 492, 493f, 505t physiologic, 500t, 502 prevalence of, 491 signs and symptoms of, 503t spasmus nutans, 502 suppression and, 498 treatment of added lenses, 504–506 contact lenses, 504 occlusion, 507–508 pharmacologic therapy, 513 pleoptics, 512 prism, 506–507 recommendations for, 514 refractive correction, 504, 510 surgery, 513–514 vision therapy, 508–512, 511f–513f vestibular, 502–503, 500t, 499 voluntary, 500t, 503 Nystagmus blockage syndrome, 501–502, 514 O Oblique astigmatism, 400 Occipitoparietal junction, 374, 376 Occlusion for amblyopia, 481–482, 482f aniseikonia and, 521 complications of refractive surgery treated with, 578–579 for cyclovertical heterophoria, 397, 397t, 416 diagnostic, 397, 397t, 521 heterophoria and, 101 prism, 507–508 sector, 416 test for, 294 Occlusion therapy ABI and, 578–579 cyclovertical heterophoria treated with, 416 for nystagmus, 507–508 as passive therapy, 89, 101, 131–132, 132t, 308, 481–482, 482f Occupational therapy, 604t Ocular bobbing, 503t Ocular flutter, 375, 375t, 503t Ocular growth component, 618–622, 621f–622f, 625 genetically programmed, 623–625, 623f–624f, 625t, 629 relative strength of, 626 variations in, 620 visually driven, 625 Ocular inflammation, 280 (c) 2015 Wolters Kluwer All Rights Reserved Index Ocular motility procedures afterimage techniques, 230–231 computer home therapy, 231 lenses, prisms, and mirrors, 221 nystagmus and, 296, 498–499 paper, pencil, and miscellaneous tasks, 222–230, 223f–225f Ocular motor apraxia, 375, 375t Ocular motor dysfunction, 64–65, 65t, 72, 83, 83f, 124 added lenses, 372 background information about, 372–373, 373f case studies of, 87, 381–385 children with, 156, 376 classification of, 59, 64–65, 65t, 72, 73t diagnostic findings for, 73t differential diagnosis of, 374–376 pursuit, 376, 376t saccadic, 375–376, 375t drugs and toxins influencing, 376, 376t functional v medically significant, 376 general management principles for, 371 NFV and, 380 PFV and, 380 prevalence of, 369 reading and, 387–388 refractive error and, 372 signs and symptoms of, 72, 373–374, 374t terminology of, 368 tests for, 373 treatment of, 89, 104–105, 377 added lenses, 371–372 prognosis of, 369–371 surgery, 385 vision therapy, 104–105, 372, 377–378, 377t–380t Visagraph II and, 372, 373f Ocular motor nerve paresis, 374, 375t Ocular motor system adaptability of, 370 assessment of, 56 OKN in, 498 problems with, 57 vestibular system in, 498–499 Ocular motor therapy, specific guidelines for, 156–157 Oculomotor paresis, 370 Oculomotor-based auditory biofeedback, 105 OEP analytical case analysis See Optometric Extension Program analytical case analysis OEP minus lens procedure See Optometric Extension Program minus lens procedure Office policy, for vision therapy, 691–692 Office space, 681 OKN See Optokinetic nystagmus Opsoclonus, 375, 375t, 503t Opthalmoscopy, 261, 476f, 498 Optokinetic nystagmus (OKN), 498 Optometric Extension Program (OEP) analytical case analysis advantages of, 52 disadvantages of, 52, 55 expected findings of, 51, 51t requirements of, 51 Optometric Extension Program (OEP) minus lens procedure, 18 Optometrists learning-related vision disorders and, 593–594, 606, 613 primary care, 112 refractive surgery and, 666–669, 666t therapists v., 678–679 Orthokeratology, 638 Orthophoria, 56, 65–68, 65t, 80–83, 84, 89 Orthopic fusion, 177, 182–183, 184 Oscillopsia, 505t, 510, 513 Out of phoropter testing, 396 P P pathway See Parvocellular pathway PALs See Progressive addition lenses Paper, pencil, and miscellaneous tasks accommodative therapy with, 218–219 advantages of, 143 classification of, 140 disadvantages of, 143 fusional vergence therapy with, 182–186, 182f–183f, 185f–186f instrumentation for, 140, 140t, 141–142, 142f ocular motility procedures for, 222–230, 223f–225f types of, 140t, 142f Papilledema, 261–262 Parallax children and, 152 definition of, 152 feedback from, 152 Paralysis of accommodation description of, 337–338 prevalence of, 338 Parametric adjustment, 370 Parents letters to, 686–688, 690–691 questionnaire for, 606–609, 607f–609f Parietal lesions, 374, 375t Parkinson disease, 375, 375t, 376t Parvocellular (P) pathway, 599 Passive therapy, 131–134, 132t, 202 for amblyopia, 481–483, 482f atropine, 131–132, 132t, 482–483 occlusion, 89, 101, 131–132, 132t, 308, 481–482, 482f Pathologic diplopia, 296–297 Patient instructions, for home-based vision therapy Ann Arbor letter tracking, 703 beads and string, 699–700 colored circle cards for convergence, 700–701 Eccentric Circles at 10–15 feet, 697–698 Eccentric Circles for convergence, 696–697 Eccentric Circles for divergence, 695–696 first- or second-degree targets at 10–15 feet, 701–702 Hart chart for saccadic therapy, 702–703 monocular loose lens rock, 704 red lens and penlight technique to eliminate suppression, 694 tranaglyph slides, 698–699 TV trainer, 694–695 visual tracing, 703–704 Patients See also Children age and intelligence of, 103–104, 361 change created by, 114 compliance of, 377, 479 counseling for, 415, 503–504 feedback provided to, 145 financial issues of, 106 frustration of, 144 history of, 494–495, 601 individual v multiple per session, 679 level of, 144, 154–155 localization cues for, 148–149 motivation of, 106, 377, 479 positive reinforcement for, 144 (c) 2015 Wolters Kluwer All Rights Reserved 717 prognosis determination for, 104–106 SILO response elicited from, 148 vision therapy issues and, 674–678, 675t Pattern glare, 600 PAVE Program See Perceptual Accuracy/ Visual Efficiency Program Payment, 682–684, 691–692 Pencil push-up treatment (PPT) effectiveness of, 244–246 technique for, 244 Pendular nystagmus, 492–493, 493f, 492t Penlight, 157 red/green glasses used with, 203, 694 in vertical prism dissociation, 204 Perceptual Accuracy/Visual Efficiency (PAVE) Program, 371 Percival’s criterion, 99–100 Peripheral fusion, 164–165 Peripheral tranaglyph targets, 161f–162f, 163 Peripheral vestibular nystagmus, 502–503 Personality testing, 602 Per-visit payment method, 683 PFV See Positive fusional vergence Phakic intraocular (IOL) lens, 656 Pharmacologic treatment with atropine, 131–132, 132t, 482–483, 618–619, 636–637 of convergence excess, 278 of myopia, 636–637 of nystagmus, 513 Phasic vergence training, 155 in accommodative infacility vision training program, 362t in basic esophoria vision training program, 324 in basic exophoria vision training program, 333 CAVT Random Dot Stereograms and, 175 in fusional vergence dysfunction vision training program, 312 with tranaglyphs, 165, 165t, 166f Phenobarbital, 376t Phenothiazides, 342t Phenytoin, 376t Phoria accommodative problems and, 133–134 associated and dissociated combinations of, 418, 418t cyclovertical, 83, 86f, 87 definition of, 389 dissociated, 49, 50f fixation disparity associated with, 431f, 432, 435 insignificant, in case analysis, 83, 87, 86f lateral associated, 432 predictors of, 460t significant, in case analysis, 76–83, 77f–79f, 83f vertical associated, 130–131, 395–396, 395f–396f, 406, 434–435 as x-intercept, 431–432, 431f–432f, 438 Phoria size and direction assessment, 3t, 5–11, 5f, 8t, 56, 100, 395, 414 AC/A ratio technique for, 9–10, 39–40 CA/C ratio technique for, 10–11 cover test for, 5–7, 5f, 6t, 36–37, 63, 118 instrumentation for, 433–434, 443t modified Thorington test for, 3, 3t, 7–8, 8t, 38–40, 63 von Graefe test for, 3, 3t, 7, 8t, 37–39, 63 Phoropter setup, in fixation disparity analysis, 434 testing outside, 8, 434 Phospholine Iodide See Echothiophate iodide Photic stimulation, 512 718 Index Photorefractive keratectomy (PRK), 656, 661–662, 669–670 Physiologic diplopia Brock string for, 142 vectogram for, 148–149 Physiologic nystagmus, 500t, 502 Pierce saccade test, 27 Pilocarpine, 280, 625 Pirenzepine, 636 Placebo effects, 336, 337 Plane of accommodation, 152–153, 152f–153f, 179, 180, 180f, 182, 182f Plane of regard, 152, 153 Plane of vergence, 152–153, 154f, 180, 180f, 182, 182f Plastic period, of amblyopia, 473 Pleoptics, 512–513 Plus lenses accommodative insufficiency treated with, 337, 343–344 amblyopia treated with, 481–482 BAF test with, 58, 327 basic esophoria treated with, 320, 320t bifocal, 97, 126, 287 convergence excess treated with, 280–281, 281, 281t CUC treated with, 550, 556–557 MAF test with, 61 at near and calculated AC/A ratio, 126–127, 127t NRA test with, 327 nystagmus treated with, 504–506 plane of accommodation influenced by, 153f prescribing of, 95–97, 95t–97t, 320 retinal images magnified by, 147 single vision, 287 Polachrome illuminated trainer, 149–150, 150f, 164, 166, 166f, 171 Polaroid bar reader, 199 Polaroid target, 17, 22, 23f, 122 Polaroids accommodative therapy with, 209–212, 210f, 211t advantages of, 141 categorization of, 138 disadvantages of, 141 fusional vergence therapy with, 160–176, 161f–163f, 164t–165t, 166f, 167t, 168f–171f, 174f, 175t instrumentation, 140–141, 140t recommended procedures for, 164t types of, 140t Positive fusional vergence (PFV) accommodative excess and, 350 in accommodative therapy, 155 analysis of, 57–59 BAF testing, 58, 237, 311, 327 fused cross-cylinder testing, 60 MEM retinoscopy testing, 58–59, 240–241, 339$$ NPC, 58–59 NRA testing, 58, 240, 311, 327 smooth vergence testing, 57 step vergence testing, 57 vergence facility testing of, 57 basic esophoria and, 309, 323 basic exophoria and, 309, 330 in binocular vision therapy, 155 convergence excess and, 282t convergence insufficiency and, 240–241 divergence excess and, 292, 298 fusional vergence dysfunction and, 312–313 normalization of, 312, 329t, 380 ocular motor dysfunction and, 380 refractive error and, 94, 292 Positive reinforcement, 144 Positive relative accommodation (PRA), 49, 50f, 56, 60–62, 73t discontinuation of, 14 tests, 3, 3t, 14–15, 19t, 42–43 for accommodative insufficiency, 340–341 for CUC, 555 with minus lenses, 319 for NFV, 59–60, 279, 319, 548 PPT See Pencil push-up treatment PRA See Positive relative accommodation Prednisolone/sulfacetamide (Blephamide) SOP, 564 Pre-Lasik monovision trial, 663–664 Presbyopia accommodative insufficiency v., 338 convergence insufficiency associated with, 255–257 Primary care optometry accommodative disorders assessment, 121–124, 121t, 123t, 124 of binocular vision disorders, 112–120, 113t–114t, 124 common vision problems analyzed in, 124 definition of, 112, 113t–114t diagnosis, 112–117, 115f, 117f of eye movement disorders, 112–134, 113t–114t model for establishment of vision therapy in fees, 679, 681, 684 home v in-office therapy, 679–680 individual v multiple patients per session, 679 insurance coverage for vision therapy, 683–684 office space, 681 payment, 682–684, 691–693 revenue and expenses, 682, 682t therapists v optometrists, 678–679 vision therapy schedule, 680–681 nonstrabismic binocular vision disorder assessment, 118–120, 124 treatment modalities, guidelines, and prognosis in, 125–134, 125t, 127t, 129t, 132t PRIO instrument, 555, 555f Prism, 120 ABI and, 578, 582–584 accommodation-vergence interactions treated with, 467 accommodative dysfunction treated with, 134, 336 accommodative therapy with, 212–218, 213f, 215f, 217f–218f advantages of, 141 amblyopia treated with, 481 bar, 140t basic esophoria treated with, 320 basic exophoria treated with, 328 BIM, 167–168, 329 BOP, 168, 320 in case analysis, 57–59, 62 categorization of, 140–141 complications of refractive surgery and, 669 conjugate, 507 convergence excess treated with, 281 convergence insufficiency treated with, 243–244, 582–584 CUC treated with, 550, 559–560 cyclovertical heterophoria treated with clinical management of vertical heterophoria and, 401t patient counseling, 415 prescription criteria for, 401t, 402–406, 405f, 407f prism adaptation, 406–408 diopter, 161 disadvantages of, 141 dissociation evaluation, 393, 395f divergence excess treated with, 295 for divergence insufficiency, 236–237, 262 dove, 425 effectiveness of, 97–101, 103t, 104, 129, 129t explanation of proposed treatment using, 677 fixation disparity analysis and, 99, 429–430 flip, 140t, 165, 165t, 176, 404, 405f, 461 fusional vergence dysfunction treated with, 312 fusional vergence therapy with, 176 horizontal, 236, 281, 295 basic esophoria treated with, 320 basic exophoria treated with, 329 description of, 97–100, 103t, 128–130 in fixation disparity analysis, 393, 405–406 latent hyperopia treated with, 407–410 lateral correction design, 439–442, 440f–441f loose, 140t, 165, 165t, 176, 221 Maddox double, 392, 393f nystagmus treated with, 506–507 occlusion, 507–508 ocular motility procedures with, 221 plane of vergence influenced by, 152–153, 154f prescription considerations of, 130 resistance to, 669 Risley, 436 treatment with, 97–101, 103t, 131–132, 132t, 320 TV trainer and, 202 vergence ranges of, 402–404 vertical prism, 100–101, 130–131, 243, 281, 295 adaptation to, 406 basic esophoria treated with, 320 basic exophoria treated with, 329 correction design, 442–443 dissociation, 204 vision therapy and, 101 PRK See Photorefractive keratectomy Progressive addition lenses (PALs), 558, 558f Proportional-controller-based negative feedback systems, 618 Proximal vergence, 456, 467 Pseudoconvergence insufficiency, 241–242, 257–258, 339, 349 Pseudomyopia See Accommodative excess Psychoeducational testing, for reading dysfunction achievement testing and, 602 basic components of, 600–602, 601t cognitive testing and, 601–602 comprehensive history and, 601 emotional or personality testing, 602 importance of, 600 previous, 604t Pull-away method, of accommodative amplitude assessment, 45 Pupil size, 556 Pursuit dysfunction, 368 functional v medically significant, 376 pathological causes of, 376, 376t saccadic v., 376 (c) 2015 Wolters Kluwer All Rights Reserved Index Pursuit eye movements, 63, 196, 197f activities influenced by, 372–373 expected values for, 32, 31t in fixation stability evaluation, 25t, 30–31, 31t, 47–48 medications influencing, 376 neurologic pathways of, 374 ocular motor dysfunction and, 376, 376t, 375t slow pursuit gain and, 376, 376t testing format for, 25t, 30–31, 31t, 47–48 Push-up amplitude test, 19–20, 18t–19t, 121–122, 121t Q Questionnaires See Symptom and quality of life questionnaires Quoit vectogram, 148–150, 148f, 150f, 152f, 166f R Radial keratotomy (RK), 530 Random Dot Stereograms, 175, 206, 231 Random dot stereopsis, in Computer Orthoptics VTS3 Liquid Crystal System, 174f, 175 Randot stereotest, 16–18, 16f–17f Rate of refractive change ametropia progression and, 626–628, 627f–628f in hyperopia, 626, 627f lenses influencing, 626 in myopia, 626, 627f Readalyzer, 25t, 26, 29–30, 602 Reading accommodative infacility influencing, 597–598 colored filters and, 598–600 comprehension of, 596t convergence excess and, 664 dynamic, 231 eye movement and, 368–369, 372–373, 381–383, 597–598 glasses and, 341, 598–600 higher cognitive processes in, 369 improvement of, 609–612 learning to read v reading to learn and, 595, 596t saccades in, 368, 372–373 signs and symptoms of problems with, 597t visual basis of, 596t Reading dysfunction comanagement of problems related to, 594, 613 definition of, 594 dyslexia v., 593, 594–595 psychoeducational testing in diagnosis of, 600–602, 601t, 603t remediation strategies for, 600 risk factors for, 605t symptoms of, 596t therapy for, 609–613 vision problems’ relationship with, 595–596, 596t–597t Recent-onset vertical diplopia, 399 Red/green bar reader, 199, 200f, 217, 217f Red/green glasses, 13, 17, 157, 160, 171, 209 in BAF therapy, 217 penlight used with, 203, 694 Red/green targets See Anaglyphs Red-red rock description and setup of, 209–210, 210f endpoint of, 210 equipment needed for, 209 objectives of, 209 Refractive amblyopia See Amblyopia Refractive correction for amblyopia, 470–480 case study of, 479 for CUC, 549–550 for cyclovertical heterophoria, 400–401 full, 131, 132t, 481–482 for nystagmus, 504 Refractive error See also Binocular vision– based model, for refractive error management accommodative dysfunction and, 335 amblyopia and, 471, 474–475 aniseikonia and, 519 basic esophoria and, 318 basic exophoria and, 326 convergence excess and, 278 convergence insufficiency and, 239 CUC and, 550–551 determination of, 2, 117–118 diagnostic testing of, 2, 117–118 distribution of, 619, 619f divergence insufficiency and, 260 fusional vergence dysfunction and, 310 guidelines for, 125t hypersensitivity to, 578 low, 94 NPC and, 326 nystagmus with, 495 ocular motor dysfunction and, 371 PFV and, 94, 292 significant degrees of, 92–93, 92t, 125, 125t type of, 93 Refractive modification, 638 Refractive state (RS) anterior chamber depth related to, 620, 621f axial length related to, 620, 621f–622f at birth, 616 changes in, from visually driven emmetropization mechanism, 649, 649t corneal curvature related to, 621, 621f genetic basis of, 618–619 lens power unrelated to, 621, 621f rates of change of, 626–628, 627f refractive error distribution and components of, 619, 619f suppression influencing, 618 Refractive surgery, 486 See also Complications, of refractive surgery LASIK, 655–660, 662–663 optometrist’s role in, 666–669, 666t phakic IOL lens, 656 popularity of, 655, 672 surface ablation techniques epi-LASIK, 656 Lasek, 656 PRK, 656, 661, 669 Regard, plane of, 152 Relative accommodation, 462 Relative distance magnification, 121 Relative stimulus strength, 157 Relative vergence, 456, 461 Remy separator, 140t, 142f See also Modified Remy separator Response CA/C, 11 Retinoscopy, 93, 117–118 book, 372 cycloplegic, 495 (c) 2015 Wolters Kluwer All Rights Reserved 719 MEM, 3t, 3, 18, 47, 55, 73t, 121, 121t, 123t, 128 for accommodative insufficiency, 339 accommodative response assessed by, 18t, 19t, 23–24, 24f, 121, 121t, 455, 555, 555f accommodative system tested by, 61, 122 cards used for, 23, 24f issues of, 122 NFV tested by, 58, 279, 327, 548 for nystagmus, 497 PFV tested by, 58–59, 240–241, 339 Nott, 18 static, Retraction, 503t Revenue, 682, 682t Reverse geometry contact lenses, 638–639, 648–649 RGP contact lenses See Rigid gas-permeable contact lenses Rheostat, 203 Rigid gas-permeable (RGP) contact lenses, 504, 637, 648 Risley prisms, 436 RK See Radial keratotomy Room illumination, 157 Rotating cylinder cyclovergence therapy, 424–425 Rotating pegboard, 225, 225f Rotator-type instruments automatic rotator, 225, 226f description and setup of, 225, 225f–226f equipment needed for, 225, 225f–226f objectives of, 225 rotating pegboard, 225, 226f RS See Refractive state S Saccades, 63, 196 accuracy disorders of, 375, 375t challenges of testing formats for, 26–27 direct observation, 27, 26t–27t in fixation stability evaluation, 25t–27t, 25–31, 28f–29f from gross to fine, 156 hypometric, 375, 375t inappropriate, 375, 375t initiation disorders of, 375, 375t main sequence of, 372 neurologic pathways of, 374 objective eye movement recording, 29–30, 28f–29f peak velocity of, 372 Pierce test for, 27 in reading, 382, 372–373 testing recommendations for, 30, 47, 56, 63 velocity disorders of, 374, 375t vergence procedures integrated with, 315, 324, 332 visual-verbal, 27 Saccadic dysfunction, 368, 373–374, 374t functional v medically significant, 376 pathologic causes of, 374–376, 375t pursuit v., 376 vision therapy for, 218–219, 702–703 Saccadomania, 375 Scotopic sensitivity syndrome, 598 Secondary vertical deviations, 419 Second-degree targets See Flat fusion targets Sensitive period, of amblyopia, 473 Sensory cyclofusion, 391 Sensory fusion deficiency See Fusional vergence dysfunction 720 Index Sensory fusion disruption syndrome, 573, 579, 588–590, 590t Sensory motor therapy, 420 Sensory status assessment, 3t, 4–5 general considerations in, 15 stereopsis evaluation in, 16–17, 16f–17f suppression evaluation in, 15–16 Septums advantages of, 141 classification of, 140 definition of, 141 disadvantages of, 141 fusional vergence therapy with, 187f–191f, 176–181, 177f–181f instrumentation, 138, 140t, 141, 142f in modified Remy separator, 180–181, 181f types of, 140t, 142f Sheard’s criterion, 49–50, 98–99, 101 SILO response See Small in, large out response Simulated divergence excess, 292–294 Single Maddox rod, 392, 393f Single vision prescriptions, 287 Sixth nerve palsy, 261–262, 269, 370 Size constancy, 146 Slab-off prism, 402, 410 Sliding vergence See tonic vergence Slit lamp evaluation, 498 Slope, of forced vergence fixation disparity curves, 430f, 430, 437–441, 437f, 438f, 440f–441f Slow pursuit gain, 376, 376t Small axis power alterations, 530 Small in, large out (SILO) response clinical relevance of, 147–148 feedback from, 145–148, 147f geometric explanation for, 147, 146f lenses and, 147 from patients, 147–148 size constancy and, 146 SOLI response v., 146 in variable tranaglyph procedures, 164, 164t vergence and, 146–148, 157f Small out, large in (SOLI) response, 146–147, 164 Smooth vergence in convergence excess therapy, 312–313 in convergence insufficiency therapy, 247 testing of, 3–4, 3t, 8t, 11, 40–42, 55, 57 amplitude v facility and, 11 of NFV, 59 of PFV, 57 step vergence v., 11 Smooth vertical vergence therapy, 422, 423f Snellen fractions, 687 Soft contact lenses, 637 SOLI response See Small out, large in response Space eikonometer accuracy of, 525 aniseikonia and525–528, 526f–527f availability of, 525 examination difficulties with heterophoria, 527, 527f monocular suppression, 527, 527f image size determination and, 527 settings of, 526–527 target of, 525–526, 526f, 527f Spasm of accommodation, 280, 349, 664 Spasm of convergence, 280 Spasm of the near reflex, 349, 353 Spasmus nutans, 502 Sphere modification, of forced vergence fixation disparity, 443–444, 445f–446f Sports/Action cards, 178f, 177 Square wave jerk, 375, 375t Standard dynamic reading, 231 Static aniseikonia, 517, 519, 529 Static retinoscopy, Step vergence testing, 3–4, 3t, 8t, 41, 55 of NFV, 59 of PFV, 57 smooth vergence v., 11 Step vergence training See Phasic vergence training Step-Jump Vergence program, 174 Stereograms, 175, 188f, 206 Stereopsis evaluation, 3t, 4, 16–17, 16f–17f, 164–165, 173, 174f, 498 Stereoscopes Bernell-O-Scope, 139f, 187f Brewster, 140t, 143 accommodative and convergence demands determined with, 188–189 convergence demand, 189 description and setup of, 187–188, 187f–188f endpoint of, 190 equipment needed for, 187 objectives of, 186 therapy procedures for, 190 cheiroscope, 140t, 420 diagnostic procedure for, 190, 191f interpretation and, 191–192, 191f Keystone Correct-Eye-Scope, 190, 191f in red-red rock therapy procedure, 210f therapy procedures for, 192, 192f circumstances requiring, 143 classification of, 140 in cyclovergence therapy, 425, 425f cyclovertical heterophoria treated with, 420 in divergence excess vision therapy, 298 double mirror, 138, 139f fusional vergence therapy with, 186–194, 187f–188f, 190f–194f haploscope, 140t instrumentation, 138, 139f, 140t, 143 stereograms for, 187, 188f tromboning and, 143, 190 Wheatstone, 140t, 143 Bernell Variable Prismatic Stereoscope, 192f, 193, 193f, 420 description and setup of, 193, 193f endpoint of, 194 equipment needed for, 193 objectives of, 193 therapy procedures for, 193, 194f Stimulus CA/C, 11 Strabismus, 460t constant, 16, 17, 319 cover test in absence of, 5, 5f, 118 decompensation of, as refractive surgery complication, 661 intermittent, 319 management of, 131 Strabismus surgery, 294, 485 Stress vertical vergence therapy, 423 Stroke See Cerebrovascular accident “Successful Treatment” determination, 89–92, 90f–91f Sulfonamides, 280 Superimposition targets, 206, 205f–206f, 298, 301, 701–702 Suppression See also Antisuppression therapy anisometropic amblyopia and, 475–476 assessment of nystagmus and, 498 other tests for, 16 scotoma size in, 15 Worth four-dot test for, 15–16 cheiroscopic tracings and, 192 environment preventing, 156–157 feedback from, 145 isoametropic amblyopia and, 475 IXT and, 643 lack of symptoms and, 106–107 monocular, 527 precipitation of, 141 RS influenced by, 618 space eikonometer and, 527, 527f therapy, amblyopia treated with, 483–485, 485f treatment for, 154, 483–485, 485f, 694 Supranuclear control centers, 374 Supravergence test, 56, 62 Surface ablation techniques, 655–656 Surgery See also Refractive surgery accommodative dysfunction and, 336 for amblyopia, 485–486 for basic esophoria, 324 for basic exophoria, 333 for convergence excess, 285 convergence insufficiency and, 251 for CUC, 551 for cyclovertical heterophoria, 425–426, 425 for divergence excess, 276, 294, 303 divergence insufficiency and, 266 effectiveness of, 107 fusional vergence dysfunction and, 309, 316 for nystagmus, 513–514 for ocular motor dysfunction, 385 strabismus, 294, 485 Sustained processing system, 599 Sustained retinal blur, 625 Symbol tracking description and setup of, 222–223, 223f–224f endpoint of, 224 equipment needed for, 222 objectives of, 222 Sympathetic paralysis, 280 Symptom and quality of life questionnaires CISS, 90–92, 90f, 112, 115, 115f COVD-QOL, 91–92, 91f, 239 VQS, 116f–117f Symptomatic cyclophoria, 400–401 Synthetic Optics targets, 17, 17f Syphilis, 280 Systematic reviews, 102, 102f Systemic toxicity, 482, 636 T Television trainer See TV trainer Testing See Diagnostic testing Thallium, 376t Therapists, optometrists v., 678–680 Third nerve paresis, 370 Three-component model of vision, 594, 594t Three-dot card, 140t, 198t Three-step test, 392, 393t, 397 Tinnitus, 505t Tonic vergence, 63, 113t, 155, 318, 326, 455f, 460t, 468 in accommodation-vergence interactions, 453–456, 457f proximal, 456, 467–468 Tonometry, 498 Track and Read program, 228–231 Training conditions, natural v artificial, 140, 157 (c) 2015 Wolters Kluwer All Rights Reserved Index Tranaglyphs, 140t, 149, 151f, 423f important factors in working with, 167 nonvariable, 170–171, 171f description and setup of, 170, 171f equipment needed for, 170 objectives of, 169–170 therapy procedures with, 171 patient instructions for, 698–699 projection of, 323, 330 variable description and setup of, 161–164, 161f–163f equipment needed for, 160 objectives of, 160 SILO response and, 164, 164t targets of, 161f–162f, 163–164 therapy procedures using, 165–168, 165t, 166f, 167t vectograms v., 168 Tranquilizers, 376, 376t Transient system deficit theory, 599–600 Transilluminator, 157 Translation, 529 Traumatic brain injury (TBI), 571, 574 Treatment See also specific treatment “Successful Treatment” determination, 89–92, 90f–91f rewards of, 108 sequences of, 92 Tromboning, 143, 190 True divergence excess, 292–294 Turville testing, 131, 395, 396f for aniseikonia, 522–524, 523f tasks based on, 140t TV trainer in antisuppression therapy, 201–202, 201 description and setup of, 201–202, 202f endpoint of, 202 equipment needed for, 201 lenses and, 202 objectives of, 201 patient instructions for, 694–695 prism and, 202 task difficulty changed with, 202 working distance of, 202 Typhoid, 343, 360t U Ultraviolet (UV) protection, 558 Unequal accommodation, 338 Unilateral cover test, 36 Unilateral high myopia, 475 UV protection See Ultraviolet protection V Variable prismatic stereoscope See Bernell Variable Prismatic Stereoscope Variable tranaglyphs description and setup of, 161–165, 161f–163f equipment needed for, 160 objectives of, 160 SILO response and, 164, 164t targets of, 161f–162f, 161–162 therapy procedures using BAF, 166 phasic, 165–166, 165t, 165f vergence at working distance, 167–168, 167t Variable vectogram, 168, 168f VDT See Video display terminal Vectograms, 140t, 423f Bernell No 9, 22, 23f for physiologic diplopia, 148–149 Quoit, 148–150, 148f–150f, 152f, 166f tranaglyphs v., 168 variable, 168, 168f Vectographic slide, 2, 54, 131, 395, 396f, 432f Velocity disorders, of saccades, 374, 375t VEP acuity threshold See Visual evoked potential acuity threshold VER See Visually evoked response Vergence, 197f See also Fusional vergence accommodation interactions with, 344, 354, 361, 430 analysis approaches to, 451–452, 452f binocular vergence, 456–460, 457f–459f, 460t clinical testing and, 460–467, 464f–467f dual interactive model of, 616–617, 617f key concepts of, 452–453, 454f lens therapy and, 467 myopia and, 632 prism therapy for, 467 relative fusional vergence and, 461 tests of, 63, 460 theoretical, 453, 454f tonic vergence, 453, 454f accommodative, 461 adaptation of, 463 ancillary testing of, 120 Computer Vergences program, 175, 175t, 206, 231 multiple choice program, 172–174, 174f phasic training for, 155, 165, 165t, 166f, 313, 322, 331t plane of, 152–153, 153f–154f, 178, 179f, 182, 182f prism ranges of, 402–404 procedures for increasing and decreasing demands of, 167, 167t saccades and versions integrated with, 315, 324, 332 proximal, 456, 467 relative, 456, 461 SILO response associated with, 145–147, 147f smooth in convergence excess therapy, 281–282 in convergence insufficiency therapy, 247 testing of, 3, 3t, 8t, 11, 40–42, 55, 57, 59 step, 3–5, 3t, 8t, 41, 55, 57, 59 tonic, 63, 113t, 155, 318, 453, 460t vertical reserves of, 404 Vergence facility testing, 3, 3t, 8t, 11–12, 40–42, 119 amplitude v facility and, 12 of NFV, 59 of PFV, 57–59 prism, 4f Vergence range testing, 119 Vergence therapy endpoint of, 168 fusional, 154 anaglyphs, Polaroids, and liquid crystal filters, 160–175, 161f–163f, 164t–165t, 166f, 167t, 168f, 705f, 174f, 175t lenses, prisms, and mirrors, 176 paper, pencil, and miscellaneous tasks, 182–186, 182f–183f, 185f–186f 192–196, 192f–193f, 196f (c) 2015 Wolters Kluwer All Rights Reserved 721 septums and apertures, 187f–191f, 176–181, 177f–181f stereoscope, 186–195, 187f–188f, 191f–194f with voluntary convergence procedures, 194–197, 195f, 197f–198f horizontal, 417–420, 418t, 508–509 phasic, 155 in accommodative infacility vision training program, 362t in basic esophoria vision training program, 324 in basic exophoria vision training program, 333 CAVT Random Dot Stereograms and, 175 in fusional vergence dysfunction vision training program, 312 with tranaglyphs, 165, 165t, 166f procedures for increasing and decreasing demands of, 167, 167t vertical, 417–418, 418t, 420–424, 423f at working distance, variable tranaglyphs and, 167–168, 167t Versions, vergence procedures integrated with, 315, 324, 332 Vertical associated phoria, 130–131 fixation disparity curves and, 406, 434 forced vergence fixation disparity curves and, 435 vertical fixation disparity analysis of, 395–396, 395f–396f Vertical deviations, 389 ABI and, 582–583 assessment of, 392–393, 394f–395f secondary, 419 well-compensated, 421 Vertical diplopia recent-onset, 399 sector occlusion and counseling treatment for, 416 Vertical fixation disparity analysis cyclofixation disparity, 396 forced vergence disparity curves and, 9, 496, 406 vertical associated phoria, 395–397, 395f VFV analysis and, 62 Vertical fusion, 62, 95, 391 Vertical fusional vergence (VFV) analysis, 62, 95 Vertical heterophoria, 57, 64, 124 clinical management of, 401t Maddox rod evaluation of, 392, 393f prism dissociation evaluation of, 392, 393f Vertical line counting, 510–511, 511f Vertical prism, 100–101, 130–131, 243, 281, 295 adaptation to, 406 basic esophoria treated with, 320 basic exophoria treated with, 329 correction design, 442–443 dissociation, 204 Vertical vergence reserves, 404 Vertical vergence therapy, 420–423 case study of, 421–422 cyclovertical heterophoria treated with, 417–418, 418t horizontal vergence therapy v., 417–418, 418t jump, 422 smooth, 422, 423f stress, 423 Vertigo, 505t Vestibular nystagmus, 498–499 central v peripheral, 502 characteristics of, 500t 722 Index Vestibular system, in oculomotor movement, 498 Vestibulo-ocular reflex (VOR), 499 VFS See Vision Function Scale VFV analysis See Vertical fusional vergence analysis Video display terminal (VDT), 547, 555 Visagraph II, 25t, 26, 29–30, 29f, 56, 372, 373f, 602 Vision deprivation, 471 Vision disorders See also specific disorder classification system of accommodative, 56, 64–65, 65t, 70–71 alternative system of, 64, 65t binocular, 56–57, 65–70, 65t, 73t, 103t, 113t–114t, 124, 129t, 292–293 case analysis and, 57–59, 64–65, 65t Duane’s, 64, 124, 309, 335 ocular motor, 57, 63, 65t, 72, 73t vertical, 57, 62, 65t, 70 identification of, 62, 65t prevention of, 52, 55 Vision Function Scale (VFS), 115 Vision Quality Scale (VQS), 116f–117f Vision shaping treatment (VST), 638 Vision therapy See also specific treatment method ABI and advice for, 580 case study of, 580–581 cognitive and perceptual problems, 579 excyclotorsion, 580 prognosis of, 578–579, 579t, 585t, 590t, 590, 590t sensory fusion disruption syndrome, 580 visual field loss, 580 for accommodative dysfunction, 335–336 for accommodative excess, 354–360, 354t, 355t–356t for accommodative infacility, 361–364, 361t–363t for accommodative insufficiency, 343, 344t–346t for amblyopia, 485 for basic esophoria indications for, 320 objectives of, 321t specific program for, 321–324, 321t–323t for basic exophoria, 307–309 length of, 329 objectives of, 329t specific program for, 329–333, 331t–332t for children, 103, 148 for complications of refractive surgery, 670–671 for convergence excess, 281, 282t, 283t–284t for convergence insufficiency, 236–237, 243–251, 670–671 child requiring, 674–676 feedback cues used in, 246t objectives of, 246t office-based, 253–259, 246t, 248t–250t specific program for, 253–259, 246t, 248t–250t for CUC, 550, 560–562 for cyclovertical heterophoria, 417–425, 423f, 425f antisuppression, 418 horizontal vergence, 417–420, 418t vertical vergence, 417, 418t, 421–423 design v implementation of, 158 for divergence excess, 275–277 Aperture Rule in, 298, 301f cheiroscopic tracings in, 302 length of, 296–297 objectives of, 297t specific program for, 296–303, 297t, 299t–301t, 301f stereoscopes in, 302 strategies for, 295–296 for divergence insufficiency, 263 guidelines for, 263 indications for, 263 objectives of, 263t office-based, 264t–265t specific program for, 263–266, 263t–265t effectiveness of, 101–103, 102f, 277, 309 evaluation for, 682 for fixation disparity, 432, 444, 446f for fusional vergence dysfunction, 154, 307–308 length of, 311 objectives of, 313t, 315 specific program for, 312–316, 314t–315t general principles and guidelines for, 144–152, 147f–152f instrumentation afterimages, 140, 140t, 143, 230 anaglyphs, 140–141, 140t apertures, 140, 139f, 140t, 141 basic, 684 categorization of, 138–139, 140t computer software, 684 electrophysiologic techniques, 140, 143 entopic phenomena, 140 for forced vergence fixation disparity curves generation, 433–434, 433t lenses, 140–142, 140t for paper, pencil, and miscellaneous tasks, 140, 140t, 141–142, 142f for phoria measurement, 433–434, 434t Polaroids, 140–141, 140t septums, 140, 140t, 141, 142f stereoscopes, 140, 139f, 140t, 143 for learning-related vision disorders, 606 lenses prescribed before, 328 as medical care, 683 misconceptions about, 678 necessity of, 103–107 for nystagmus biofeedback, 508–513, 511f–513f categorization of, 508 fusion enhancement, 508–509 for ocular motor dysfunction, 156 computers in, 377–378 effectiveness of, 105, 370–372 objectives of, 377t prognosis of, 369–371 specific program for, 370–372, 377–378, 378t–380t office policy for, 691–692 patient and practice management issues in case presentation, 674–677, 675t communicating findings, 678 insurance coverage, 683–684 model for establishment of vision therapy in primary care practice, 678–684, 682t, 691–692 planning and monitoring, sphere modification in, 444, 446f prism and, 101 procedures, categorization of, 138–144, 139f, 140t, 142f saccadic, 221–222, 702–703 time course of, 107 variety in, 143 Visual acuity, 495–497, 496f, 631, 687 Visual efficiency disorders, 604–605, 606–613, 687–688 Visual evoked potential (VEP) acuity threshold, 495 Visual field defects, 375, 375t, 579 Visual field testing, 498 Visual growth mechanism, 618 Visual system, deterioration of, 52, 55 Visual tracing, 140t description and setup of, 224, 224f endpoint of, 225 equipment needed for, 224 objectives of, 224 patient instructions for, 703–704 Visually driven ocular growth, 625 Visually evoked response (VER), 477 Vitamin B1, 280 Voluntary convergence procedures Barrel card, 140t, 197, 198f Brock string, 194–197, 195f–197f fusional vergence therapy with, 193–197, 195f, 197f–198f Voluntary nystagmus, 500t, 503 Von Graefe test accommodation control for, phoria assessed with, 3, 3t, 7, 8t, 37–39, 63 Von Noorden amblyopia classification, 472, 472t VOR See Vestibulo-ocular reflex VQS See Vision Quality Scale VST See Vision shaping treatment W Wallenberg syndrome, 375, 375t Wechsler intelligence tests, 601 Welch Allyn retinoscope, 23 Well-compensated vertical deviations, 421 Wesson cards, 54, 396f, 432f, 435f Wheatstone stereoscopes, 140t, 143 Bernell Variable Prismatic Stereoscope, 192f, 193, 193f, 420 description and setup of, 193, 193f endpoint of, 194 equipment needed for, 193 objectives of, 193 therapy procedures for, 193, 194f Whole line dynamic reading, 231 Woolf card, 432f Workstation evaluation, 554, 570 Worth four-dot test, 3t, 4, 15–16, 44 Written correspondence insurance letters, 683–684, 688–690 letters to parents, 686–688, 690–691 reports, 102, 102f, 678 Z Zone of singular binocular vision, 463 (c) 2015 Wolters Kluwer All Rights Reserved ... importance of carefully evaluating eye movement skills and always being cognizant of the differential diagnosis of eye movement disorders, as well as accommodative and binocular vision disorders. .. five sets of Groffman tracings without error • Fuse with a convergence demand of 30 base-out and a divergence demand of 15 base-in • Complete 12 cpm of accommodative facility with +2. 00/ 2. 00 lenses... exists, treatment of eye movement disorders may lead to improvement in attention and concentration (38–41) There have been few studies of the prevalence of eye movement disorders, particularly in