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8 104 Complications of Excimer Laser Surgery blows nitrogen gas during ablation has decreased the occurrence of central islands. Central islands are usually characterized by undercorrection accompanied by monocular diplopia. With topography, the central elevated area is clear. ese symptoms oen disappear in 3 to 6 months. Several attempts have been made to treat symptomatic central islands [9, 21]. e topography-linked or wavefront-guided laser ab- lation is a helpful tool. Fig. 8.2 Retinal images. Top: wavefront analysis. e higher order aberration is 1.14 μm. Bottom: the reti- nal image evaluated by wavefront analysis (pupil size, 3 mm). e blurred image le improved aer surgery (right) Fig. 8.3 Orbscan (irregular astigmatism). Top : kera- tometric map shows irregular astigmatism. e visual acuity is 0.7 (1.5 × sphere: –0.5 D; cylinder: –2.0 D; axis: 153°). e patient complained of monocular dip- lopia during the day and at night. Bottom: aer wave- front-guided laser ablation, the uncorrected visual acuity improved to 1.5 8.3 Intraoperative Complications 105 8 106 Complications of Excimer Laser Surgery 8.3.4 Undercorrection Undercorrection is the result of incorrect preop- erative evaluation of refraction, excessive mois- ture in the stromal bed, decentration, and prob- lems with laser calibration. If the preoperative refraction is unstable, the refraction should be Fig. 8.4 Retinal images. Top: wavefront analysis. e higher order aberration is 0.66 μm. Bottom: the reti- nal image evaluated by wavefront analysis (pupil size, 3 mm). e blurred image (le) improved aer surgery (right) repeated aer an interval and the ablation post- poned. If the patient uses hard contact lenses, the refraction should be done at least 2 weeks aer the patient stops wearing them. Because the re- fraction is the key to achieving successful results, the examination should be repeated until the sur- geon is comfortable with the status of the refrac- tion. Some patients require more than 2 months to obtain a stable refraction aer wearing contact lenses. If the cycloplegic refraction diers sub- stantially from the non-cycloplegic refraction, the refraction should be repeated using both val- ues at another visit. Using uncertain refractive results will cause unnecessary complications. Excessive moisture in the stromal bed can re- sult in undercorrection. is oen happens when the surgeon is inexperienced. Undercorrection also can result if the patient’s xation is poor and the laser is not ideally applied. e laser calibra- tion is also important. e laser operator should be aware of the condition of the laser. e laser should be recalibrated with each use. Enhancement usually results in good refrac- tive outcomes. e timing of the enhancement surgery depends on the cause of the undercor- rection. If the refraction is stable, retreatment can be done at any time. To avoid repeating the problems that arose in the initial surgery, the cause should be well considered. In addition, the postoperative corneal thickness should be conrmed. If the total corneal thickness is less than 400 μm, further laser ablation should be avoided to prevent corneal ectasia. e patient’s age also should be considered. If the patient is over 40 years, monovision may be an option. A surgeon can perform unilateral enhancement and see both far and near visual function. Some patients enjoy unplanned monovision. 8.3.5 Overcorrection e causes of overcorrection are similar to those of undercorrection: the accuracy of the refrac- tion, the condition of the stromal bed, and the laser calibration. Dryness of the stromal bed usu- ally causes overcorrection. If the surgeon delays starting the laser ablation, the cornea becomes dry and the eect of the laser is intensied. Tran- sient overcorrection aer PRK is a well-known phenomenon. Although this problem has de- creased with the latest generations of excimer lasers, the changes in the refraction should be observed over time. Patient age also plays an important role. Younger patients can tolerate overcorrection; however, older patients are very sensitive to over- correction. Unfortunately, the risk factors for overcorrection are age and attempted correction. e higher these factors are, the more frequently patients encounter this complication. If overcorrection occurs aer PRK, the admin- istration of steroid eye drops should be stopped. Some physicians also recommend stopping the use of articial tears. Regarding hyperopic cor- rection, transient overcorrection is the goal be- cause subsequent regression is common. Patients should be well informed about this before sur- gery. e treatment of overcorrection aer the treatment of myopia is mandatory. Recently, the use of diclophenac eye drops with contact lenses produced good results. If the correction meets the desired target, the eye drops should be stopped immediately. If this does not change the results, excimer laser with hyperopic correction or holmium laser thermoplasty is frequently per- formed. Summary for the Clinician ■ Preoperative examination of the refrac- tion and calibration of the laser are fun- damental to achieving the best visual outcomes. ■ Corneal topography should be per- formed even if the patient achieved good visual outcome to conrm the ideal laser ablation. ■ Wavefront-guided ablation is a helpful tool in patients with decentered ablation or irregular astigmatism. 8.4 Postoperative Complications Even though patients achieve good outcomes, some complications can develop later. Since pa- 8.4 Postoperative Complications 107 8 108 Complications of Excimer Laser Surgery tients enjoy their improved uncorrected visual acuity, even a slight decrease in visual acuity is unacceptable. However, the cause of decreased uncorrected visual acuity should be well evalu- ated and the treatment planned. 8.4.1 Regression Regression is a common problem for any laser surgery including LASIK. If regression occurs, retreatment is considered. Regression accompa- nied by corneal haze requires a dierent treat- ment approach, such as the application of steroid eye drops, PRK, or phototherapeutic keratec- tomy (PTK). Recently, the use of beta-blocker eye drops to decrease the intraocular pressure has achieved good results. e eect of improv- ing the vision in these cases is still under dis- cussion. Why beta-blocker eye drops work and Latanoprost eye drops do not is a question for future research. is approach does not work in every case; however, it is worth trying beta- blocker eye drops. e interval since the time of laser surgery, patient gender and age, and the pre- operative refraction are not correlated with the amount of improvement. If this does not produce a satisfactory result, retreatment is planned aer conrming that the refraction is stable. Gener- ally, enhancements should be planned at least 3 months aer the previous surgery. If the cor - rection exceeds 6 D, waiting more than 6 months may be necessary to achieve a stable refraction. 8.4.2 Corneal Haze Corneal haze is a well-known complication aer PRK. Histopathologic and confocal microscopic studies revealed that haze is induced by activa- tion and proliferation of corneal keratocytes [3]. e haze usually appears 1–3 months aer sur - gery and gradually resolves within 1 year. With slit-lamp microscopy, subepithelial haze can be observed in the central area and classied from grades 0 to 4 [16]. Recently, objective scoring was introduced using digital images and con- focal microscopy [2, 6, 10]. e incidence of haze was higher with previous laser treatment [30]; however, the incidence decreased with re- cent technological advances that produced a smoother ablation. e risk factors are greater tissue ablation such as in the treatment of high myopia, ultraviolet exposure, atopic dermatitis, and autoimmune conditions [8, 12, 24]. Despite the appearance of haze, most cases achieve good visual acuity. If the haze becomes substantial, the best-corrected visual acuity decreases with some regression (Fig. 8.5). Problems may develop with night vision and decreased contrast sensitivity [13, 18]. Most surgeons use steroid eye drops immediately or shortly aer laser treatment and gradually taper the drops. Although the eects of corticosteroid eye drops used clinically have been positively or negatively reported, theoretical ben- ets have been described in experimental stud- ies. Special attention should be paid to the side eects of corticosteroids, especially increased intraocular pressure. Recently, the eects of chilled irrigation solu- tion and mitomycin C were reported. Mitomy- cin C is used for glaucoma ltering surgery and pterygium surgery and has been introduced into laser surgery [17, 28, 34]. e concentration of mitomycin C and the duration of its application have been discussed; 0.01 mg/ml is the mini - mum concentration reported to be eective and 0.4 mg/ml is the maximum to avoid complica - tions [4]. e 0.02% concentration is widely used. Aer laser application, a 6-mm diameter Fig. 8.5 Corneal haze. e best corrected visual acuity decreases sponge is soaked in 0.02% mitomycin C diluted with balanced saline solution (BSS) and applied over the ablated cornea for 2–3 min. e eye then is washed with BSS. Complications such as thinning of the scleral tissue and delayed epithe- lialization were reported in cases of glaucoma-l- trating surgery and pterygium. An experimental study showed dose-dependent corneal edema and endothelial apoptosis. However, the prophy- lactic use of 0.02% mitomycin C in laser surgery seems to be safe and eective at preventing haze [33] and achieved better visual acuity [7]. Mito- mycin C is also used to treat haze [20, 29] in the same technique used during PRK, or the drug can be administered as an eye drop. Use of vita- min C and amniotic membranes also have been reported; however, the eects need to be studied further [33, 36]. 8.4.3 Delayed Epithelialization Following PRK, LASEK, and Epi-LASIK, ban- dage contact lenses are applied. Aer 3 days, most eyes achieve re-epithelialization and the contact lenses can be removed. e preservative in the eye drops sometimes delays the recovery of the epithelium. e use of eye drops without pre- servatives is preferable. If the eye developed epi- thelial problems due to the toxicity of eye drops, the drops should be discontinued. 8.4.4 Infections Infections aer refractive surgery are rare, but can be the most severe complications aer any ophthalmic surgery. Regarding laser surgery, corneal opacity remains even though the infec- tion was treated with antibiotics. e common cause is staphylococcus and mycobacteria; the prophylactic application of antibiotics is recom- mended [15]. An epithelial defect is the optimal site for the development of a bacterial infection. If the process of re-epithelialization is prolonged, spe- cial steps should be taken to avoid infections. In LASIK cases, the focus of the infection is under the ap and the risk of perforation increases. Cultures should be performed to conrm the bacteria in severe cases; however, topical antibi- otics should be started immediately. Liing the ap and irrigation are necessary in certain cases. Aer treatment, PTK can be performed if the opacity remains on the corneal surface. Penetrat- ing or lamellar keratoplasty is needed in patients with poor visual acuity. Infection usually results in poor corrected visual acuity. 8.4.5 Adverse Eects on the Corneal Endothelium Experimental and clinical studies have shown no side eects from refractive procedures on the corneal endothelium [3, 11]. One study reported that the number of endothelial cells decreased af- ter a tranquilizer was administered to the patient before PRK [25]. 8.4.6 Corneal Ectasia Aer LASIK was introduced, a new complica- tion, keratectasia, was reported [5, 26, 31] in which continuous regression with irregular astigmatism develops. e risk factors are form fruste keratoconus, thin cornea with high myo- pia, and pellucid marginal degeneration. Preop- erative evaluation with corneal topography and pachymetry are necessary. e postoperative corneal condition should be assessed to maintain a corneal thickness greater than 400 μm or a re - sidual stromal bed greater than 250–300 μm. En - hancements performed without measuring the corneal thickness can cause ectasia. Orbscan can be performed to diagnose kera- tectasia. e posterior oat map shows obvious thinning. If this complication occurs, hard con- tact lenses are tted. If the vision cannot be cor- rected with contact lenses, ICR or cross-linking may be performed, followed if not successful by corneal transplantation. If the surgeon does not recognize the corneal thinning and continues to treat with the excimer laser to improve the vi- sion, the cornea may be perforated. 8.4 Postoperative Complications 109 8 110 Complications of Excimer Laser Surgery Summary for the Clinician ■ Some postoperative complications are well treated with eye drops. ■ Regarding postoperative complications concerning the refractive error, en- hancement should be considered when the refraction is conrmed to be stable. ■ Before enhancement, the corneal thick- ness and shape should be considered. ■ Some postoperative complications are related to the failure of the indication. References 1. Alkara N, Genth U, Seiler T. Diametral abla- tion—a technique to manage decentered photore- fractive keratectomy for myopia. J Refract Surg 1999;15:436–440. 2. Allerman N, Charmon W, Silverman RG, et al. High-frequency ultrasound quantitative analysis of corneal scarring following excimer laser kera- tectomy. Arch Ophthalmol 1993;111:968–973. 3. Amm M, Wertzel W, Winter M, et al. Histopatho- logical comparison of photorefractive keratec- tomy and laser in situ keratomileusis in rabbits. J Refract Surg 1996;12:758–766. 4. Ando H, Ido T, Kawai Y, et al. Inhibition of corneal wound healing. Ophthalmology 1992;99:1809–1814. 5. Argento C, Cosentino MJ, Tytium A, et al. Cor- neal ectasia aer laser in-situ keratomileusis. J Cataract Refract Surg 2001;27:1440–1448. 6. Braustein RE, Jain S, McCally RL, et al. Objec- tive measurement of corneal light scattering af- ter excimer laser keratectomy. Ophthalmology 1996;103:439–443. 7. Carons F, Vigo L, Scadola E, Vacchini L. Evaluation of the prophylactic use of mitomycin C to inhibit haze formation aer photorefractive keratectomy. J Cataract Refract Surg 2002;28:2088–2095. 8. Carson CA, Taylor HR Excimer laser treatment for high and extreme myopia. Arch Ophthalmol 1995; 113:431–436. 9. Castill A, Romero F, Martin-Valverde JA, et al. Management and treatment of steep islands aer excimer laser photorefractive keratectomy. J Re- fract Surg 1996;12:15–20. 10. Chew SJ, Beuerman RW, Kaufman HE, et al. In vivo confocal microscopy of corneal wound heal- ing aer excimer laser photorefractive keratec- tomy. CLAO J 1995;25:273–280. 11. Colin J, Cochener B, Le Floch G. Corneal en- dothelium aer PRK and LASIK. J Refract Surg 1996;12:674. 12. Corbett MC, O’Brart DPS, Warburton FG, Mar- shall J. Biological and environmental risk factors for regression aer photorefractive keratectomy. Ophthalmology 1996;103:1381–1391. 13. Corbett MC, Prydol JI, Verma S, et al. An in vivo investigation of the structures responsible for cor- neal haze aer photorefractive keratectomy and their eect on visual function. Ophthalmology 1996;103:1366–1380. 14. Doanne JG, Cavanaugh TB, Durrie DS, Hassa- nein KH. Relation of visual symptoms to topo- graphic ablation zone decentration aer excimer laser photorefractive keratectomy. Ophthalmol- ogy 1995;102:42–47. 15. Donnefeld ED, O’Brien TP, Solomon R, et al. Infectious keratitis aer photorefractive keratec- tomy. Ophthalmology 2003;110:740–747. 16. Fantes FE, Hanna KD, Waring GO III, et al. Wound healing aer excimer laser keratomileusis (photorefractive keratectomy) in monkeys. Arch Ophthalmol 1990;108:665–675. 17. Gambato C, Ghirlando A, Moretto E, et al. Mito- mycin C modulation of corneal wound healing af- ter photorefractive keratectomy in highly myopic eyes. Ophthalmology 2005;112:208–218. 18. Hersh PS, Stulting RD, Steinert RF, et al. e Summit PRK Study Group. Results of phase III excimer laser photorefractive keratectomy for myopia. Ophthalmology 1997;104:1535–1553. 19. Krueger R, Saedy NF, McDonnell PJ. Clinical analysis of steep central islands aer excimer laser photorefractive keratectomy. Arch Ophthalmol 1996;114:377–381. 20. Majmudar PA, Forstot SL, Dennis RF, et al. Topi- cal mitomycin C for subepithelial brosis af- ter refractive corneal surgery. Ophthalmology 2000;107:89–94. 21. Manch EE, Maloney RK, Smith RJ. Treatment of topographic central islands following refractive surgery. J Cataract Refract Surg 1998;24:464–470. 22. Mulhern MC, Foley-Nolan A, O’Keefe M, et al. Topographical analysis of ablation centration aer excimer laser photorefractive keratectomy and laser in situ keratomileusis for high myopia. J Cataract Refract Surg 1997;23:488–494. 23. Nagy ZZ, Hiscott P, Seitz B, et al. Ultraviolet- B enhances corneal stromal response to 193- nm excimer laser treatment. Ophthalmology 1997;104:375–380. 24. Nakaya-Onishi M, Kiritoshi A, Hasegawa T, et al. Corneal endothelial cell loss aer excimer laser keratectomy, associated with tranquillizers. Arch Ophthalmol 1996;114:1282–1283. 25. Pallikaris IG, Kymionis GD, Astyrakakis NR. Cor- neal ectasia induced by laser in-situ keratomileu- sis. J Cataract Refract Surg 2001;27:1796–1802. 26. Pande M, Hillman JS. Optical zone centration in keratorefractive surgery; entrance pupil cen- ter, visual axis, coaxially sighted corneal reex. Or geometric corneal center? Ophthalmology 1993;100:1230–1237. 27. Porges Y, Ben-Haim O, Hirsh A, et al. Photothera- peutic keratectomy with mitomycin C for corneal haze following photorefractive keratectomy for myopia. J Refract Surg 2003;19:40–43. 28. Raviv T, Majmudar PA, Dennis RF, et al. Mitomy- cin-C for post-PRK corneal haze. J Cataract Re- fract Surg 2000;26:1105–1106. 29. Seiler T, Holschbach A, Derse M, et al. Com - plications of myopic photorefractive keratec- tomy with the excimer laser. Ophthalmology 1994;101:153–160. 30. Seiler T, Koufala K, Richter G. Iatrogenic keratec- tasia aer laser in-situ keratomileusis. J Refract Surg 1998;14:312–317. 31. Stojanovic A, Ringvoid A, Nitter T. Ascorbate prophylaxis for corneal haze aer photorefractive keratectomy. J Refract Surg 2003;19:338–343. 32. Suzuki T, Bissen-Miyajima H, Nakamura T, et al. Use of mitomycin C for enhancement following photorefractive keratectomy (in Japanese). Jpn J Clin Ophthalmol 2004;58:461–464. 33. Talamo JH, Collamudi S, Green WR, et al. Modu- lation of corneal wound healing aer excimer la- ser keratomileusis using topical mitomycin C and steroids. Arch Ophthalmol 1991;109:1141–146. 34. Tamayo GE, Serrano MG. Computerized topo- graphic ablation using the VisX CAP method. In: MacRae SM, Krueger RR, Applegate RA, eds. Customized corneal ablation. orofare, NJ: SLACK, 2001. 35. Tsai Y, Lin JM. Ablation centration aer active eye-tracker-assisted photorefractive keratectomy and laser in situ keratomileusis. J Cataract Refract Surg 2000;26:28–34. 36. Wang MX, Gray TB, Park WC, et al. Reduction in corneal haze and apoptosis by amniotic mem- brane matrix in excimer laser photoablation in rabbits. J Cataract Refract Surg 2001;27:310–319. References 111 Core Messages ■ Refractive lens exchange in myopic eyes carries a signicant risk of postoperative retinal detachment. ■ Particular risk factors are: ■ Higher myopia; ■ Younger age, (less then 50 years); ■ Surgical complications (capsule rup- ture and vitreous loss); ■ Neodymium:YAG capsulotomy re- lation to rhegmatogenous retinal detachment aer refractive lens ex- change is controversial and indeter- minate 9.1 Introduction About 60 years ago the concept of intraocular lens implantation was pioneered. About 30 years ago, small incision lens extraction by phacoemulsi- cation was realized. Both pioneering eorts have subsequently led to perfecting the respective pro- cesses. us, refractive surgery, the correction of ametropia through lens-based surgery was initiated. e era of corneal laser surgery com- mencing about 25 years ago focused public and professional attention on the wider opportunity for permanent refractive correction and thereby created in practice the sub-specialty of refractive surgery. Lens-based refractive surgery was side- tracked for a time as the surgical process matured until it was able to oer ophthalmic surgeons with that interest more security and scope for in- tervention. Initially, surgical techniques evolved more rapidly than lens implant technology. e crystalline lens, whether cataractous or ‘clear,’ could be removed by sub-2.5-mm incisions. However, intraocular lens implants (IOLs), made of PMMA before the foldable materials were ap- proved, required a 5- to 6-mm incision, not the ideal basis for a refractive surgical procedure. Gradually, though, lens implants became more rened and eventually developed spectacularly in form, eect, and enhanced small incision ca- pability, an essential component of the refractive surgical process. Today, modern lens extraction and implant replacement is a safe, predictable, and stable process in general; however, nothing is absolute in this sense. All surgeons are aware that no surgical intervention is absolutely risk-free. As we age, the crystalline lens is the ever-chang- ing element in the eye. Its replacement (the lens implant) provides a permanent result in the op- tical sense, leaving the cornea for enhancement of eect if necessary. As with all surgical proce- dures there are risk factors to be weighed against the benets. Refractive surgery in general is about risk management. One issue that requires in-depth exploration is retinal complications of refractive surgery. is applies in particular to refractive lens exchange (RLE) and especially its application in myopic eyes, which are more vul- nerable in the retinal sense than hyperopic eyes. 9.2 RLE: Need to Know A refractive surgeon needs to know the risks inherent in an RLE procedure, risks for hyper- metropic eyes, and those for myopic eyes. e surgeon needs to know the risk odds so that the patient can be reliably informed what they are getting into. In the case of myopic eyes, evidence suggests that the degree of myopia or size of the globe is one type of risk that could be graded. Age is another as is surgical complications. A study of the literature enables the risks to be quantied, Refractive Lens Exchange: Risk Management Emanuel Rosen Chapter 9 9 9 114 Refractive Lens Exchange: Risk Management despite the signicant variations in study proles (Tables 9.1, 9.2). e literature is an aid to learning about the risk of RLE as well as the outcomes from cata- ract and lens implant surgery in myopic eyes. It is necessary to dene risk factors as well as the outcome for myopic and hyperopic eyes that have suered pseudophakic retinal detachments. Surgical complications are fortunately very rare in eyes undergoing RLE in experienced surgical hands. However, what are the risks and potential outcomes if complications do occur? 9.3 Cystoid Macular Edema ere are other retinal risks of RLE apart from rhegmatogenous retinal detachment (RRD), but they are of less importance in incidence and ef- fect. Cystoid macular edema, which if unre- solved will lead to permanent visual impairment through cystoid macular changes, is fortunately rare following uncomplicated surgery. It tends to be transient, causing short-term visual distur- bances. Invariably, it will resolve with appropri- ate anti-inammatory medication for it is medi- ated by the post-surgical inammatory cascade and temporary loss of the blood–retinal barrier. e incidence and causes of clinical and angio- graphic cystoid macular edema (CME) aer un- complicated phacoemulsication and intraocu- lar lens implantation in otherwise normal eyes were investigated by Mentes et al. [31]. Clinical and uorescein angiographic macular edema was evaluated 45 days postoperatively in a study comprising 252 eyes following uncomplicated phacoemulsication with in-the-bag acrylic IOL implantation. Clinical CME was not detected in any eye at any postoperative visit, but angio- graphic macular edema was detected in 9.1% of eyes. e visual outcome did not dier between eyes with no clinical edema and those with fun- dus uorescein angiography-detected edema. Treatment of clinically evident and visually dis- abling CME aer RLE is by topical application of steroidal and non-steroidal anti-inammatory agents coupled with low-dose acetazolamide. Only in circumstances where there is a poor re- sponse to topical therapy should systemic high- dose, short course steroid therapy be contem- plated. Other aids include sub-Tenon’s steroid or as a last resort intraocular steroids though this is a remote requirement. 9.4 Risk Management and Rhegmatogenous Retinal Detachment A meta-analysis of papers concerning the inci- dence of retinal detachment aer lens extraction and IOL implantation for 12 years between 1994 and 2005 reveals that these studies are not uni- form in their protocols (Table 9.1) and most were retrospective reviews. ere were many variables that have to be evaluated in an attempt to isolate the identiable risk factors for RRD [1–3, 5–7, 9–12, 14, 16, 18–20, 22, 23, 25, 26, 28–30, 32, 36, 39, 40, 43–45, 48, 50, 52–54]. Factors not apparent from this study, but hinted at in some papers, are the consistently inuential factor of age of the patient. Younger patients, i.e., less than 50 years old, have a dis - proportionately higher risk of RRD according to the general cataract studies of Polkingshorne and Craig [38], e.g. less than 50 years related to an in - cidence of 5.1% RRD (which is a more relevant rate for RLE comparisons) whereas over 70 years the rate was less than 0.7% [8]. One hundred and forty-one patients presented between May 1997 and April 1998 with an RRD, i.e., an annual inci- dence of 1.18 cases per 10,000 people (0.0118%), 5 of whom presented with bilateral RRD and the mean age at presentation was 53.9 years. RRD was more common in males than in females with a ratio of 1.3:1. Ocular trauma, high myopia, and Table . Meta analysis publications on refractive lens exchange (RLE) and myopic cataract surgery (1994– 2005): variables Variables include: Eye axial length Number of eyes studies Follow up duration and range Neodymium:YAG capsulotomy rates Pre-operative retinal prophylaxis Patient age range Operative complications [...]... Follow-up 3–60 months cataract extraction were found to be significant risk factors in the development of RRD Lois and Wong [ 27] quoted an incidence of RRD after phacoemulsification cataract surgery ranging from 0 to 3.6% and averaging 0 .7% in the general population They calculated that the excess risk of developing a retinal detachment after cataract surgery in the first 10 years over eyes without surgery. .. [52] 1999 38 0 .7 1 [12] 2002 72 0 .7 1 [39] 1995 430 0.8 4 [18] 19 97 386 0.8 1 [28] 1996 109 0.9 2 [25] 19 97 90 1.1 1 ECCE [50] 2003 73 1.3 1 Aphakia [32] 1998 245 1.4 4 ECCE [22] 2002 125 1 .7 2 [9] 1999 118 1 .7 2 [10] 2004 190 2.1 4 [30] 2005 194 2.1 4 [36] 2002 151 3.0 4 [16] 2005 37 3.2 2 [26] 1994 136 3.6 4 [40] 2001 25 4.0 1 [45] 1999 166 4.8 8 [3] 1998 33 6.1 2 [44] 2003 930 8.0 72 [44] 2003 1020... visual outcome and KPE intraoperative complications including: posterior capsular rupture, vitreous loss, and posteriorly dislocated lens fragments Christensen et al [4] compared pre- and postoperative findings in 120 pseudophakic patients and 280 phakic patients who had RRD surgery over a 4-year period An identical scleral buckling procedure was used for primary surgery in both groups Cataract surgery had... risk factor above and beyond the general risk because of its inherent retinal instability as defined by the above statistics Ripandelli et al [44] discussed cataract surgery as a risk factor for retinal detachment in very highly myopic eyes Studying 930 in a retrospective, paired-eye, case-control trial in which axial length ranged from 29 .7 to 35.5 mm with a follow-up of 36 months and an neodymium:... RLE /cataract surgery is usually assumed to be causally related to the lens surgery The evidence for this relation has been based on the observed frequency of such events following cataract surgery, particularly the excess frequency previously observed after intracapsular cataract extraction Such studies were characterized by the lack of a control group of patients who did not have lens surgery and. .. 0.022% = 2.2:10,000 Phakic blunt trauma 0.009% = 0.9:10,000 Nontraumatic 0.006% = 0.6:10,000 [ 47] General population 0.2% = 20:10,000 [35] More than -1 0 D 0.68% = 68:10,000 [38] After KPE 1. 17% = 1 17: 10,000 70 years 0 .7% = 70 :10,000 Pseudophakia and aphakia 0.008% = 0.8:10,000 [ 17] [24] 0.005% = 0.5:10,000 Overall incidence of RRD following RLE for myopia 2.2% = 220:10,000... retinal detachments occurring in the first year after surgery were the result of the surgery Ivanesivic and colleagues [ 17] studied the epidemiological characteristics of non-traumatic phakic RRD in a defined population of a county in Croatia Of 278 eyes ( 272 patients) developed RRD during an 11-year period, 1988–1998, with a population of 465,9 47 The annual incidence was 0.54 per 10,000 of the population... eyes in 3 patients (18 .75 %) • Mean preoperative spherical equivalent (SE) was – 17. 3±2. 47 D (range, –13 .75 D to –22 D) 9 • Rhegmatogenous retinal detachment occurred between 1 and 70 months after PCP IOL implantation (mean, 29.12 months) • Each of 11 RRDs (68 .75 %) had one causative break • Fourteen breaks (60.86%) were horseshoe tears and 9 (39.14%) were atrophic holes Polkinghome and Craig [38] suggest... after cataract surgery These included Nd:YAG laser capsulotomy (odds ratio [OR] = 3.8; 95% confidence interval [CI], 2.4–5.9), a history of retinal detachment (OR = 2 .7; 95% CI, 1.2–6.1), a history of lattice degeneration (OR = 6.6; 95% CI, 1.6– 27. 1), axial length (OR = 1.21 mm; 95% CI, 1.03–1.43), refractive error (OR = 0.92/diopter; 95% CI, 0.88–0.95), and a history of ocular trauma after cataract surgery. .. warrant that degree of follow-up observation On the other hand Sharma et al [46] studied 64 patients with an RRD in one eye, but who were phakic in the fellow eye During an average follow-up of 57. 4 months, 5 (7. 8%) fellow eyes developed retinal detachment while still phakic In addition to the 5 eyes with a phakic RD, 10 originally phakic fellow eyes underwent cataract surgery Of these, 1 (10%) suffered . chilled irrigation solu- tion and mitomycin C were reported. Mitomy- cin C is used for glaucoma ltering surgery and pterygium surgery and has been introduced into laser surgery [ 17, 28, 34]. e concentration. Astyrakakis NR. Cor- neal ectasia induced by laser in-situ keratomileu- sis. J Cataract Refract Surg 2001; 27: 179 6–1802. 26. Pande M, Hillman JS. Optical zone centration in keratorefractive surgery; entrance. scleral tissue and delayed epithe- lialization were reported in cases of glaucoma-l- trating surgery and pterygium. An experimental study showed dose-dependent corneal edema and endothelial
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