98 Chapter 2 ◆ Optic ataxia: clumsiness or inability to manually respond to visual stimuli, with mislocation in space when pointing to visual targets. ◆ A disturbance of visual attention: resulting in dynamic concentric narrowing of the effective fi eld. ◆ Simultagnosia: an inability to recognize the whole picture despite the ability to perceive its parts. ◆ Inferior altitudinal fi eld defect: not part of Balint syndrome, but upper banks of occipital cortex are usually involved. 3 Treatment: ◆ According to the etiology of stroke. Cavernous sinus syndrome 1 Tumors ◆ Most common cause. ◆ The most common neoplastic lesion in the cavernous sinus is caused by direct invasion from nasopharyngeal carcinoma. Metastatic lesions are the second most common. • The cavernous sinus is a small but complex structure consisting of a venous plexus, carotid artery, cranial nerves, and sympathetic fi bers, surrounded by a dural fold. • The third, fourth cranial nerves, as well as the fi rst and second divisions of the trigeminal nerve (V1 and V2), lie along the lateral wall of the cavernous sinus, whereas the sixth cranial nerve, internal carotid artery, and the third-order oculosympathetic fi bers from the superior cervical ganglion lie more medially. • According to the anatomy described above, cavernous sinus involvement would be suggested by any combination of unilateral third-, fourth-, or sixth-nerve dysfunction, accompanied by hypesthesia of the forehead, cornea, or cheek, or by Horner syndrome. Various degrees of pain may be involved. Complete interruption of all three ocular motor nerves would result in total ophthalmoplegia, ptosis, and/or mydriasis. • Although the classical syndrome of cavernous sinus results from aneurysm or carotico-cavernous fi stula, the most common causes of cavernous sinus lesions include tumors, trauma, and infections. • Except for sparing of V2, lesions of the superior orbital fi ssure are clinically diffi cult to distinguish from those of cavernous sinus, and the differentials are similar. In orbital apex syndrome, patients present with third-, fourth-, and sixth-nerve palsies, V1 distribution sensory loss, oculosympathetic paresis, and visual loss due to optic nerve involvement. Clinical Syndromes 99 2 Trauma ◆ Trauma is reported to be the most common cause of cavernous sinus syn- drome when surgical cases are included. 3 Infections or cavernous sinus thrombophlebitis ◆ Thrombophlebitis of the cavernous sinus is potentially a lethal condition, caused by bacterial or fungal invasion, complicating sinusitis in patients with poorly controlled diabetes or immunosuppression. ◆ Rhinocerebral mucormycosis is a common cause in poorly controlled diabetics. ◆ Aspergillosis arises most commonly as a result of hematogenous spread, and occasionally by direct extension of infection from the paranasal sinuses, mid- dle ear, or orbit in immunocompromised patients. ◆ Actinomycosis gains access to the cavernous sinus by direct extension from the ear, sinus, and less commonly, hematogenous spread. Most patients are immunocompetent. 4 Tolosa-Hunt syndrome ◆ Tolosa-Hunt syndrome is a recurrent painful ophthalmoplegia due to nonspe- cifi c granulomatous infl ammation in the anterior cavernous sinus, superior orbital fi ssure, or orbital apex. ◆ Rare cause of cavernous sinus syndrome. ◆ The diagnosis is based on fi ndings of painful ophthalmoplegia, accompanied by variable defi cits of cranial nerves in the cavernous sinus, excellent response to corticosteroid therapy, and exclusion of other causes. 5 Carotico-cavernous fi stula (CCF) ◆ CCF usually result from traumatic laceration of the carotid artery or from rupture of an aneurysm into the surrounding venous sac, establishing a direct communication between internal carotid artery and the venous spaces of the cavernous sinus. ◆ Pulsating exophthalmos, orbital pain, and, eventually, restriction of eye move- ments due to orbital congestion. 6 Other rare causes ◆ Aneurysm of the internal carotid artery ◆ Infl ammatory pseudotumors Central pontine myelinolysis (CPM): causes • Central pontine myelinolysis (CPM) is a demyelinating disease of the pons, frequently associated with demyelination of other areas of the central nervous system. The term ‘osmotic demyelination syndrome’ is used for pontine and extrapontine myelinolysis (CPM/EPM). • The etiologies of CPM/EPM vary. However, almost all cases are related to severe illnesses, with chronic alcoholism being the most common underlying condition. A signifi cant high percentage of CPM/EPM cases were also observed among liver transplant patients. 100 Chapter 2 Disease Percentage of CPM/EPM cases Chronic alcoholism, including liver transplant patients 41% Electrolyte disturbances, particularly hyponatremia, but also hypernatremia 32% Pulmonary infections, including pneumonia, abscess, and tuberculosis 10% Malignant tumors, especially of the lungs and GI tract 6% Diseases of the CNS, including hemorrhage, infection, infl ammation, and tumors 7% Non-alcoholic liver disease 5% Ref: Lampl C., Yazdi K. Central pontine myelinolysis. Eur Neurol, 2002; 47: 3–10. Cerebellopontine angle syndrome Schwannoma Meningioma Involvement of cranial VIII early: originating from vestibular division, later causing pressure on the acoustic component. Later, involves cranial nerves V, IX, X May initially present with facial palsy. Late involvement of cranial VIII Positive for S-100 staining Negative EMA staining Positive for epithelial membrane antigen staining (EMA) No desmosomes Presence of Luse bodies Presence of Antoni type A, B tissue (characteristic feature) Elongated intertwined cell processes, joined by desmosomes • The role of hyponatremia and its correction in the pathogenesis of CPM is unclear, although multiple factors are most likely involved. It is important to recognize that CPM/EPM may be seen when plasma sodium levels are high, low, or normal. • CPM/EPM should be considered in patients suffering from chronic alcoholism, electrolyte disturbances, liver transplantation, or other chronic diseases when presenting with massive mental status changes as well as brainstem symptoms despite negative CT or MRI. MRI fi ndings may lag behind clinical presentation, up to weeks in some cases. • The two most common adult tumors in the cerebellopontine angle region are vestibular schwannoma and meningioma. Clinical Syndromes 101 Other causes: • Craniopharyngioma • Glomus jugulare tumor • Aneurysm of the basilar artery • Large intra-axial brainstem or cerebellar tumors Geschwind syndrome Horner syndrome • A consistent personality alteration seen in some patients with complex partial seizures. • Clinical features include: ◆ circumstantiality, ◆ hypergraphia, ◆ altered sexual status, and ◆ intensifi ed cognitive and emotional states. • Horner syndrome results from damage to ocular sympathetic fi bers at any level along the symapathetic pathway; central, preganglionic, or postganglionic neurons. • Features of Horner syndrome includes: ◆ Mild ptosis: paresis of Müller muscle ◆ Miosis: paralysis of pupillary dilator muscle ◆ Ipsilateral anhidrosis ◆ Apparent enophthalmos ◆ Heterochromia iridis: usually in congenital cases ◆ Lower eyelid reverse ptosis • Pharmacologic testing: ◆ Confi rm the diagnosis of Horner syndrome by instillation of 4–10% cocaine solution in each eye, which will dilate normal eyes only. ◆ Once the diagnosis is confi rmed, 1% hydroxyamphetamine can be used to differentiate central and preganglionic from postganglionic lesions. Because hydroxyamphetamine stimulates the release of norepinephrine from sympathetic postganglionic nerve terminals, it will fail to dilate the pupil in patients with postganglionic lesions. • Differentiation of lesions is clinically useful because central and preganglionic lesions are likely to have more serious causes than postganglionic lesions. 102 Chapter 2 The oculosympathetic pathway consists of a three-neuron arc. The fi rst-order neurons of the sympathetic pathway originate in the posterior hypothalamus, descend to the intermediolateral gray column of the spinal cord, and synapse at the ciliospinal center of Budge at spinal levels C8 to T2. Preganglionic second-order neurons arise from the intermediolateral column, leave the spinal cord by the ventral spinal roots, and enter the rami communicans. They join the paravertebral cervical sympathetic chain and ascend through this chain to synapse at the superior cervical ganglion. Postganglionic third-order neurons originate in the superior cervical ganglion, entering the cranium with the internal carotid artery. The fi bers join the ophthalmic division of the trigemi- nal nerve within the cavernous sinus, reaching the ciliary muscle and pupillary dilator muscle by means of the nasociliary nerve and the long posterior ciliary nerves. 1 Central lesions: ◆ Vascular events, e.g. Wallenberg syndrome ◆ Tumor, e.g. brainstem tumor 2 Preganglionic lesions: ◆ Apical lung tumor (Pancoast tumor) 3 Postganglionic lesions: ◆ Neck trauma ◆ Spontaneous dissection of the carotid artery ◆ Cluster headaches Kluver-Bucy syndrome Etiologies include: 1 Herpes simplex encephalitis 2 Pick disease 3 Anoxic-ischemic lesions in the anterior medial temporal lobe 4 After bilateral temporal lobectomy 5 Rarely seen in: ◆ Alzheimer disease ◆ Huntington disease ◆ Creutzfeldt-Jakob disease • Due to bilateral lesions of the amygdala. • Characterized by: ◆ chronic amnesia, ◆ distractibility, ◆ hyperorality, ◆ hypersexuality, ◆ affective dyscontrol, and ◆ socially inappropriate behavior. Clinical Syndromes 103 Orbitofrontal syndrome Common etiologies of orbitofrontal syndrome: 1 Traumatic brain injury: most common ◆ The most common injury to the orbitofrontal cortex results from closed head trauma with contusion of the inferior frontal cortex and adjacent white matter connections by the irregular bony surface of the anterior fossa. 2 Subfrontal neoplasm ◆ The second most common etiology. ◆ Neoplasm may arise from adjacent structures including pituitary fossa, olfac- tory groove, or sphenoidal ridge. ◆ In these locations, the following are particularly frequent: ■ Meningioma ■ Chromophobe pituitary adenoma 3 Others ◆ Aneurysm of the anterior communicating artery ◆ Frontotemporal dementia Thoracic outlet syndrome • Behaviorally, the outstanding feature of orbitofrontal syndrome is disinhibition and impulsiveness. Patients lack social judgement, make tactless and socially inappropriate comments. Sexual preoccupation and inappropriate sexual comments are frequent, but overt sexual aggression is rare. • The patients’ insight into their own behavior is limited. • A variety of mood changes have been described in these patients, including emotional lability, mania, and depression. • Most patients with orbitofrontal syndrome have a normal neurological examination as well as minimal neuropsychological defi cits. Therefore, careful observation of the above symptoms is of utmost importance. Anosmia can be the only physical fi nding. • It is diffi cult to make the diagnosis of true thoracic outlet syndrome (TOS), as the condition is poorly defi ned and there are no specifi c neurological or electrophysiological studies that can be used to defi nitively confi rm the diagnosis. • True compression and dysfunction of the brachial plexus is rare, and even recognized experts in the fi eld have seen few cases. • The term ‘thoracic outlet syndrome’ is often used loosely in describing patients with chronic shoulder/limb pain. 104 Chapter 2 1 Etiology: ◆ The condition is usually caused by a fi brous band traversing the brachial plexus. ◆ Cervical ribs are commonly associated with TOS, but also are present in many asymptomatic persons. ◆ Abnormal insertion of the scalene muscles is often proposed as a rationale for surgery. However, the low response rate to this procedure casts doubt as to there being a causal relationship. 2 Signs and symptoms (may be neurological and/or vascular): ◆ Patients usually present with weakness, pain, and numbness in the hand, in a pattern consistent with median and ulnar nerve (posterior trunk) involvement. ◆ In another type of thoracic outlet syndrome, patients can present with numb- ness, tingling, and pain without demonstrable neurological defi cit. The symp- toms may depend on arm and shoulder position. ◆ Aching pain is usually reported in the shoulder, upper back, and/or upper arm. ◆ Compression of the subclavian vein results in vascular congestion of the arm. ◆ Compression of the subclavian artery can result in distal limb ischemia. 3 Diagnosis: ◆ Electrophysiological investigations demonstrate reduced sensory action po- tentials in the little fi nger and medial forearm, and denervation changes in many intrinsic hand muscles (in both ulnar and median nerves) and some- times in the muscles of the forearm that contain a C8 component. ◆ Some patients can have normal studies. 4 Treatment: ◆ Physiotherapy over a period of several months. ◆ In some centers, a removal of the fi rst rib has been performed through a transaxillary approach, although the response is not consistent. ◆ Surgical section of the scalene muscles rarely improves symptoms. Tolosa-Hunt syndrome • Loss or reduction of the radial pulse during various maneuvers [such as tilting the head back and toward the affected side (Adson test) or abducting and externally rotating the shoulder (Wright maneuver)] is not entirely reliable. • Tolosa-Hunt syndrome refers to a granulomatous infl ammation at the superior orbital fi ssure or in the cavernous sinus, causing multiple cranial nerve palsies and severe pain. Clinical Syndromes 105 1 Etiology: ◆ A low-grade, granulomatous, noninfectious, infl ammatory process adjacent to the cavernous sinus or within the superior orbital fi ssure lasting weeks or months. ◆ Differential diagnosis includes tumor, infection, aneurysm, or carotico- cavernous fi stula. 2 Signs and symptoms: according to the structures located at the superior orbital fi ssure. ◆ CN V1 distribution: steady, unremitting retro- and supraorbital pain ◆ CN III, IV, VI: painful ophthalmoplegia ◆ CN V: diminished corneal refl ex ◆ CN V2: diminished sensation and pain in the V2 distribution ◆ Less commonly: optic nerve and oculosympathetic pathway involved 3 Treatment: ◆ The pain and diplopia dramatically improve with systemic corticosteroids. ◆ Spontaneous remission has been reported. Wernicke encephalopathy and Korsakoff syndrome 1 Etiology: ◆ The condition is caused by thiamine or vitamin B 1 defi ciency. These are usu- ally associated with nutritional defi ciency, most commonly and classically in alcoholism, but they can also be seen in hyperemesis gravidarum or cancer. 2 Pathology: ◆ Wernicke encephalopathy is characterized by neuronal loss, demyelination, and gliosis in periventricular gray matter regions. • Wernicke encephalopathy is the neurological manifestation of thiamine defi ciency. • Not all patients with Wernicke encephalopathy and Korsakoff syndrome exhibit the complete triad (or tetrad) of ◆ (dietary defi ciency), ◆ oculomotor abnormalities, ◆ cerebellar dysfunction, and ◆ altered mental status. • Therefore, it is important to administer large doses of parenteral thiamine to all patients with undiagnosed altered mental status, oculomotor disturbances, and ataxia. • This condition is treatable if promptly recognized and evaluated. However, patients usually progress to stupor and coma if untreated. 106 Chapter 2 ◆ Structures commonly involved include medial thalamus, mamillary bodies, periaqueductal gray matter, cerebellar vermis as well as oculomotor, abducens, and vestibular nuclei. 3 Symptoms and signs: ◆ Onset is usually abrupt but insidious onset can occur. ◆ In the classical syndrome, patients present with encephalopathy, ophthalmo- plegia, and ataxia in the setting of nutritional defi ciency. The complete triad or tetrad of symptoms are present in only one-third of reported cases. ◆ The most common ocular abnormality is nystagmus. Others include abducens nerve palsy, oculomotor nerve palsy, horizontal and vertical gaze palsy. ◆ Ataxia is usually cerebellar. ◆ Cognitive impairment mainly involves global confusion with defective imme- diate and recent memory. ◆ The major long-term complication of Wernicke encephalopathy is Korsakoff amnesic syndrome. This syndrome is primarily a disorder of anterograde greater than retrograde amnesia. Language is not usually affected, although patients may exhibit disorientation due to recent memory impairment. Con- fabulation and lack of insight are also common. 4 Diagnosis: ◆ Based on suggestive clinical history and physical fi ndings as described above. ◆ CT may demonstrate symmetrical low density abnormalities in the dien- cephalon and periventricular regions, which enhance after contrast injection. Gross hemorrhages are uncommon. ◆ MRI fi ndings of increased T2W signal intensity in the diencephalon, midbrain, and periventricular regions can be seen and are very suggestive of the diagnosis when present in alcoholics. 5 Treatment: ◆ Prompt treatment with large doses of parenteral thiamine administration. ◆ Ocular abnormalities usually improve within hours to days, and ataxia and confusion within days or weeks. ◆ Gastrointestinal absorption of thiamine is unreliable in alcoholics and malnour- ished patients. Therefore, oral administration is usually not recommended. 107 Chapter 3 Vascular Neurology Evaluation for stroke 108 Is it a stroke? Differential diagnosis 108 Focal vs. nonfocal: Neurological symptoms of transient ischemic attack or stroke 110 Clues to the etiology of TIA or stroke from physical examination 111 Craniocervical bruits 112 Stroke types 113 Cerebral hemorrhage 113 Etiology of primary intracranial hemorrhages based on the patient’s age and location 113 Subarachnoid hemorrhage (SAH): causes 114 Intracerebral hemorrhage (ICH) 115 Multiple intracerebral hemorrhages 116 Primary intraventricular hemorrhage 117 Intracranial aneurysms: description and types 118 Intracranial aneurysms: locations and associations 119 Intracranial aneurysms: patterns of hemorrhage from a ruptured aneurysm 120 Abrupt severe headache: ‘worst headache of my life’ 121 Cerebral ischemia/infarction 122 Causes of transient focal neurological symptoms (in addition to TIA) 122 Cerebral embolism: causes 124 Stroke in a young person (under age 40 years) 126 Unusual causes of TIA or stroke 127 Venous versus arterial infarcts 129 Intracranial venous thrombosis: causes 130 Stroke syndromes 131 Large vessel syndromes 131 Ocular stroke 131 Neurological symptoms and arterial territory 131 The anterior (carotid) system 132 Posterior (vertebrobasilar) system 134 Neurological Differential Diagnosis: A Prioritized Approach Roongroj Bhidayasiri, Michael F. Waters, Christopher C. Giza, Copyright © 2005 Roongroj Bhidayasiri, Michael F. Waters and Christopher C. Giza [...]...108 Chapter 3 Anterior cerebral artery (ACA) Middle cerebral artery (MCA) Clinical deficits suggesting posterior circulation involvement Moyamoya syndrome 136 137 139 139 Lacunar syndromes (LACS) 140 Brainstem and cerebellar syndromes Midbrain syndromes Pontine syndromes Lateral versus medial medullary syndrome 141 141 1 43 145 Specific differentials Illicit drugs and stroke... central finger-like lesions Empty delta sign Ref: Modified from Warlow C.P., Dennis M.S., van Gijn J., et al Stroke: A Practical Guide to Management Blackwell Science Oxford 1996: p.160 130 Chapter 3 Intracranial venous thrombosis: causes • • • Intracranial venous thrombosis is an under-recognized condition This diagnosis should be considered in any patients with primary intracerebral hemorrhage The diagnosis. .. Antiphospholipid syndrome Red flush skin Polycythemia vera Thrombosed veins/needle tracks Intravenous drug use with or without right-sided endocarditis Lax skin Ehler-Danlos syndrome Pseudoxanthoma elasticum Behçet disease Neurofibromatosis Orogenital ulcers Café-au-lait spots 112 Chapter 3 Craniocervical bruits • • Many structures in the neck area can cause local bruits Of those, the most important is the local... endocarditis Dysrhythmias: most common atrial fibrillation 1.2 Paradoxical emboli: For paradoxical emboli to occur, there has to be a right-to-left shunt So the DDx comes from that: ASD, VSD with right-to-left shunt Patent foramen ovale with shunt Pulmonary AVM 1 .3 Other structural sources, for example, aortic atherosclerotic plaques 2 Unknown etiology (27%) Surprisingly, this is the second most common... ■ ■ Vascular Neurology 127 3 Arteriopathy: divided into narrowing of the lumen due to deposition (atherosclerosis) and vessel wall problems 3. 1 Cerebrovascular atherosclerosis (18%) 3. 2 Non-atherosclerotic arteriopathy (19%) – suggests vessel wall problems – so the DDx may be generated from the following conditions: Dissection Fibromuscular dysplasia (most common in middle-aged female, ICA) Inflammation,... focal neurological deficit present at the time of examination The absence of persistent neurological deficit by no means excludes a stroke in patients who have suffered a sudden decline in neurological function It may represent a delay in presentation, signs that have resolved, or subtle signs that have been missed In patients without obvious focal neurological signs, look specifically for visuospatial-perceptual... larger than 25 mm (giant aneurysms) more often behave like space-occupying lesions 85–95% of aneurysms involve the circle of Willis and 5–15% are located in the vertebrobasilar circulation The most common locations are: 1 The anterior communicating artery (30 %) 2 The junction of posterior communicating with internal carotid artery (25 30 %) 3 The bifurcation of internal carotid and middle cerebral artery... cerebellar artery (1 3% ) Associations: 1 Polycystic kidney disease (PKD) ◆ Autosomal dominant ◆ 10 30 % of patients with PKD have intracerebral aneurysms 2 Fibromuscular dysplasia ◆ 25% of patients have aneurysms 3 Family history ◆ Aneurysms found in 9.5% of patients with a family history of intracranial aneurysms 4 Coarctation of aorta; anomalies of the circle of Willis 5 Moyamoya disease 6 Ehler-Danlos syndrome... rapid in onset and follows the resolution of focal positive neurological symptoms of migraine aura Vomiting, in general, tends to occur well into migraine attack, in contrast to SAH, which usually occurs soon after the onset 2.2 Post-traumatic headache Immediately after a head injury, there is often headache due to soft-tissue damage Post-trauma, intracranial vessels dilate, giving rise to a pulsating... Multiple sclerosis ◆ Peripheral lesions ■ ■ ■ 110 Chapter 3 Focal vs nonfocal: Neurological symptoms of transient ischemic attack or stroke • • • The anatomical location as well as the nature of neurological symptoms of a TIA or stroke reflect the area of the brain that has been deprived of blood supply or compromised by hemorrhage or edema Focal neurological symptoms are those which arise from a disturbance . 130 Stroke syndromes 131 Large vessel syndromes 131 Ocular stroke 131 Neurological symptoms and arterial territory 131 The anterior (carotid) system 132 Posterior (vertebrobasilar) system 134 Neurological. Giza 108 Chapter 3 Anterior cerebral artery (ACA) 136 Middle cerebral artery (MCA) 137 Clinical defi cits suggesting posterior circulation involvement 139 Moyamoya syndrome 139 Lacunar syndromes. lesions 110 Chapter 3 Focal vs. nonfocal: Neurological symptoms of transient ischemic attack or stroke Focal neurological symptoms suggestive of TIA or stroke Non-focal neurological symptoms Motor