14 - Systemic Conditions

Question 1

Myasthenia Gravis - Introduction

Answer 1

1. Immunological disorder with variable and fatigable weakness
2. Usually a systemic disorder, 1/2 of affected patients have ocular symptoms at onset
3. Due to Ab that reduces number of nicotinic Ach receptors
4. May be worsened or unmasked by antiarrhythmics, statins, antibiotics, chemotherapeutics, antiepileptics, quinolones, penicillamines, steroids, B-blockers, Ca+ channel blockers

Question 2

Myasthenia Gravis - Clinical Presentation

Answer 2

1. Fluctuation and fatigability (not always) usually worse in AM and may improve with rest
2. Most common sign is unilateral or bilateral ptosis
3. More ptosis in evening or prolonged upgaze
4. Cogan eyelid twitch → elicited by look in downgaze followed by upgaze and see brief over-elevation of upper eyelid
5. Enhancement of ptosis → when more ptotic eyelid elevated manually the less ptotic eyelid falls and keeps with Hering’s Law of equal and simultaneous innervation
6. Fatigue of ptosis → ask patient to sustain upgaze for 1 minute
7. Diplopia may be variable and may stimulate CN paresis → CN 4, CN 3, INO, gaze palsy, isolated muscle palsy (IR for example), total ophthalmoplegia. Any changing pattern of diplopia with or without ptosis suggests MG
8. Orbicularis oculi weakness often present in patients with ocular MG and can be crucial in differentiating MG from other causes of external ophthalmoplegia
9. Pupil contains muscarinic Ach receptors thus pupils not abnormal
10. Systemic signs → dysathria, dysphagia, dyspnea, hoarseness, weakness in mastication muscles, weakness in extensors of neck, trunk, limbs
11. Dyspnea and dysphagia can be life-threatening and require prompt treatment
12. TED may be seen in 5% of MG patients.

Question 3

Myasthenia Gravis - Diagnosis

Answer 3

1. Clinically with typical signs and symptoms, pharmacologically via acetylcholinesterase inhibitors, serologically via Ach-Ab or anti-Muscle specific Ab, electrophysiologically via EMG results
2. Edrophonium chloride → short acting acetylcholinesterase inhibitor; sleep test; ice-pack test can all be used to confirm diagnosis
   
   1. Edrophonium side effects → bradycardia, bronchospasm, cholinergic crisis, respiratory arrest, syncope as well as less serious side effects of sweating, lacrimation, abdominal cramping, nausea, vomiting, salivation, fasciculations. Consult PCP in patients with cardiac or respiratory issues. Atropine Sulfate should be available and some pre-treat with atropine. Negative test does not rule out MG
   2. Neostigmine Methylsulfate Test →Useful for children and adults who require longer obervation period than that allowed by edrophonium. Similar adverse reactions to edrophonium. Inject atropine and neostigmine simultaneously and observe for improvement.
   3. Sleep test → After baseline measurement of ptosis, patient rests quietly with eyes closed for 30 minutes and measurement of improvement suggestive of MG
   4. Ice Pack Test → Helpful if patient has ptosis. Ice pack places over slightly closed eyes for 2 minutes. Improvement may occur; however in patient with complete myasthenic ptosis colling effect may be insufficient
3. AchR-ab tests → binding, blocking, modulating. Binding most specific seen in 50-70% with ocular MG and 90% systemic MG. Blocking rarely present 1%, Modulating seen in 50-70% with ocular MG and 90% systemic MG. Modulating and Blocking done if Binding negative and MG still suspected.
4. MusK can confirm diagnosis in those without AchR antibodies. MusK patients tend to have prominent bulbar symptoms and present rarely with only ocular symptoms.
5. EMG → decremental response
   
   1. Single fiber EMG most sensitive
6. Screen MG patients for thymoma via CT chest
7. Due to coexistence of other autoimmune diseases → serology testing for thyroid dysfunction + SLE

Question 4

Myasthenia Gravis - Treatment

Answer 4

1. Pharmacological → acetylcholinesterase inhibitors aka neostigmine, pyridostigmine, corticosteroids, immunosuppressants
2. Thymectomy should be done in patients with generalized MG
3. Should be co-managed with neurologist given chance of respiratory distress
4. If ocular for 2 years then disease likely to remain ocular

Question 5

Sarcoidosis - Introduction

Answer 5

1. Commonly diagnosed in those 20-40 yo
2. More common in AA than whites and more common in females
3. Lungs most frequently involved, eyes, heart, skin, lacrimal glands, liver, lymph nodes, MSK
4. Neurological manifestations → meningitis, hydrocephalus, hypothalamic and pituitary involvement, seizures, encephalopathy, Dural venous thrombosis, vasculitis, myelopathy, peripheral neuropathy
5. 30-60% of cases discovered on routine CXR

Question 6

Sarcoidosis - Manifestations

Answer 6

1. Iritis, cataract, vitritis, retinal vasculitis, chorioretinitis
2. After facial nerve, optic nerve frequently affected either as a papillitis or retrobulbar optic neuropathy. May see sarcoid granuloma at optic nerve head
3. May infrequently cause neuroretinitis, optic perineuritis, papilledema. May see chiasmal and retrochiasmal pathway involvement. May see CN palsies, gaze palsy, tonic pupil, Horner syndrome, Argyll Robertson pupil

Question 7

Sarcoidosis - Diagnosis and Treatment

Answer 7

1. Clinical symptoms, radiographic signs, histology
2. Neurosarcoidosis → some have normal MRI. Most common neuroimaging abnormalities are meningeal and leptomeningeal enhancing lesions, no specific signs
3. Serum markers → ACE (60% sensitive) and lysozyme (70% sensitive). Hypercalcemia 10-13%, hypercalciuria 3x more common
4. Chest Xray or high-resolution CT chest obtained due to frequency of pulmonary involvement
5. FDG-PET may be helpful to assess inflammatory activity and extent of disease
6. Histology of conjunctiva, lacrimal glands, lymph nodes, or lungs may show noncaseating granulomas
7. Corticosteroids and immunomodulatory (methotrexate, TNF blockers) mainstays of tx

Question 8

Chronic Progressive External Ophthalmoplegia

Answer 8

1. Inherited mitochondrial myopathy with slowly progressive symmetric ophthalmoplegia with or without ptosis
2. Majority have mitochondrial DNA deletions or point mutations BUT nuclear mutations may occur
3. Most commonly sporadic inheritance. Also can be mitochondrial, autosomal
4. Majority may have difficulty reading and visual impairment
5. MG may be in differential though less variability of symptoms and signs in CPEO
6. Clinical findings develop between 18-40 yo
7. Systemic signs may be generalized weakness
8. Histology → ragged red fibers, mitochondrial proliferation, inclusion body abnormalities within motochondria
9. Kearns-Sayre Syndrome → includes CPEO, pigmentary retinopathy, cardiac conduction abnormalities, cerebellar ataxia, deafness, elevated CSF protein levels. Cardiac evaluation essential to rule out conduction defects and should be obtained in all patients with CPEO.

Question 9

Oculopharyngeal Dystrophy

Answer 9

1. Progressive bilateral ptosis followed by dysphagia and proximal muscle weakness
2. Most have ophthalmoplegia that when asymmetric may cause diplopia
3. Vacuolar myopathy on histology
4. French-Canadian ancestry
5. Triplet repeat expansion PABPN1

Question 10

Myotonic Dystrophy

Answer 10

1. Ophthalmoplegia may mimic CPEO
2. Symptoms start in late childhood → myotonia, exacerbated by excitement, cold, fatigue, will not be able to release handgrip quickly, affects distal musculature first, wasting of temporalis and masseter muscle (hatchet face), frontal balding, ptosis, pigmentary retinopathy, ophthalmoparesis, polychromatic lenticular deposits, miotic pupils that react poorly to light, low intelligence, insulin resistance, hearing loss, cardiomyopathy, cardiac conduction abnormalities, testicular atrophy, uterine atony,
3. EMG can show characteristic changes, genetic testing can be confirmatory

Question 11

Multiple Sclerosis - Introduction

Answer 11

1. Inflammatory and neurodegenerative disorder of CNS causing progressive neurologic disability over time
2. Patient have frequent visual symptoms
3. More common in whites and women. Most common in those 25-40 yo
4. Uncommon in children and older than 50
5. Vitamin D deficiency a risk factor, increased in first-degree relatives with MS, strong association with HLA-DRB1
6. 85% relapsing-remitting course with episodes of neurological dysfunction separated months to years in time
7. Pathological disease burden accumulates even in absence of clinical activity
8. 5-10% experience a bengn course
9. Demyelinating disease with axonal loss. Axonal loss seen as black holes on MRI
   
   1. Myelin destruction with removal by macrophages and astrocytic proliferation with production of glial fibrils → multiple sclerosis = numerous gliotic sclerotic plaque lesions. Plaques seen in white matter at ventricular margins, optic nerves, chiasm, corpus callosum, spinal cord, brainstem, cerebellar peduncles

Question 12

Multiple Sclerosis - Clinical Presentation

Answer 12

1. Nonocular signs may precede or follow ocular signs
   
   1. Cerebellar dysfunction → ataxia, dysarthia, intention tremor, truncal or head titubation, dysmetria (poor depth perception)
   2. Mental changes → emotional stability, depression, irritability, fatigue, cognitive dysfunction (later)
   3. Motor symptoms → extremity weakness, facial weakness, hemiparesis, paraplegia
   4. Sensory symptoms → paresthesia of face or body in a band like pattern, Lhermitte sign (electic shock sensation in limbs and trunk from neck flexion)
   5. Sphincter disturbances → frequency, urgency, hesitancy, incontinence, retention leading to UTIs
2. Many symptoms of MS are so transient and benign that patient may fail to remember episodes → significant episodes last weeks to months. Symptoms often so evanescent and unaccompanied by objective neurological findings that symptoms may be ignored
3. Ask about transient diplopia, ataxia, patchy paresthesias, bladder or bowel dysfunction, extremity weakness. Fatigue and depression common and precede onset of neurological deficits
4. Cerebellum, brainstem, spinal cord may be affected

Question 13

Multiple Sclerosis and Optic Neuritis

Answer 13

1. After recovering from vision loss from demyelinating disease patients may experience transient deterioration of vision during exercise or small elevations in body temperature → Uhthoff phenomenon
2. Phosphenes → bright flashes of light with movement of affected eye
3. Photisms → Light induced by noise, smell, taste, touch
4. 25% of patients have optic neuritis as presenting symptom of MS. Symptoms of optic neuritis appear in 75% of patients with MS
5. Strongest predictive factor in determining likelihood that MS would develop was presence or absence of abnormalities on MRI of brain
6. Clinically definite MS developed in 50% of patients in 15 years in ONTT

Question 14

Multiple Sclerosis Eye Findings

Answer 14

1. Uveitis x10 more common
   
   1. MS-related uveitis presents as intermediate uveitis including pars planitis and common findings include mild vitritis with periphlebitis
2. Ocular inflammation may develop concurrently, prior to or after development of neurologic signs and symptoms
3. White matter within optic chiasm, optic tracts, visual radiations frequently involved in MS
   
   1. Progressive multifocal leukoencephalopathy (PML) should be considered when a patient with MS using natalizumab presents with homonymous visual field defects
4. Motility abnormalities → supranuclear, nuclear, fascicular portions of EOM system.
   
   1. Bilateral INO → exotropia in primary position, bilaterally impaired adduction. Highly suggestive of MS in patient under 50 yo
   2. May see complete or partial horizontal or vertical gaze or skew deviation
   3. Consider MS in young patient with ocular motor CN palsy with no hx of trauma
   4. Nystagmus → horizontal, rotary, vertical, pendular, jerk. Concomitant vertical and horizontal nystagmus occuring out of phase may produce elliptical eye movements suggestive of MS
   5. Cerebellar eye dysfunction → rebound nystagmus, macrosaccadic oscillations, saccadic dysmetria, abnormal pursuit movements
   6. Dorsal midbrain syndrome may be seen

Question 15

Multiple Sclerosis - Diagnosis

Answer 15

1. Clinical
2. CSF may show elevation of IgG, elevation of IgG/albumin, presence of oligoclonal IgG bands in CSF and not in serum. None of these are specific for MS
3. Neuroimaging
   
   1. MRI with FLAIR and gadolinum-DTPA infusion → Multifocal lesions that are periventricular and ovioid most consistent.
   2. Lesions seen on MRI may fluctuate over time
   3. Hypointense regions on post-contrast T1 (black holes) also a marker of progressive disease
   4. Lesions in optic nerve in patients with acute optic neuritis best visualized on MRI with fat-suppression and gadolinium-DTPA

Question 16

Multiple Sclerosis - Treatment

Answer 16

1. No cure but therapies to alleviate symptoms
2. High-dose IV steroids used acutely
3. Disease modifying therapy recommended for long-term treatment
4. Macular edema may be seen in patients using fingolimod for MS. More common in patients with diabetes or uveitis and more likely to develop within 4 months of initial treatment

Question 17

Neuromyelitis Optica - Clinical Presentation

Answer 17

1. Inflammatory CNS disorder associated with AQP4-IgG
2. Severe attacks of optic neuritis + longitudinally extensive transverse myelitis
3. Distinct from MS via clinical, radiographic, serologic features
4. Optic neuritis typically severe → VA < 20/200 and associated with poor recovery
5. May have recurrent optic neuritis
6. May affect optic chiasm and optic tracts resulting in bitemporal or homonymous hemianopic visual field defects
7. May see nystagmus (upbeat, downbeat, mixed horizontal-torsional), INO, opsoclonus 2/2 brainstem lesions
8. Transverse myelitis → weakness or numbness of limbs, deficits in sensation and motor skills, dysfunctional sphincters, dysfunction of autonomic nervous system, refractory hiccups and vomiting due to caudal medullary lesions (area postrema and nucleus tractus solitarius)

Question 18

Neuromyelitis Optica - Diagnosis

Answer 18

1. AQP4-IgG positive in 25% patients
2. MRI → more longitudinally extensive lesions than MS. Lesions usually around 3rd ventricle, cerebral aqueduct, corpus callosum, dorsal midrain around 4th ventricle. May also see extensive and confluent hemispheric white matter lesions mimicking PRES syndrome. Spinal cord MRI shows contiguous T2 abnormality extending 3 or more segments

Question 19

Neuromyelitis - Treatment

Answer 19

1. Acute attacks → IV steroids for 3-5 days 1g
2. If no improvement with steroids → plasmapheresis
3. IVIG may be used
4. Immunosuppressive → azathioprine, mycophenolate, rituximab after initial attack
5. Disease modifying drugs for MS may exacerbate NMO → interferon-beta, natalizumab, fingolimod

Question 20

Neurocutaneous Disorders - Introduction

Answer 20

1. AKA phakomatoses → characterized by presence of hamartomas involving different organ systems such as skin, eyes, CNS, viscera
2. NF1, tuberous sclerosis, von Hippel-Lindau, Ataxia-telangiectasia, Sturge-Weber, Wyburn-Mason, incontinentia pigmenti, Klippel-Trenaunay-Weber
3. Hamartomas → tumors composed of elements normally found at site. Not true neoplasms because lack ability for limitless proliferation
4. Choristomas → tumor-like growth factors composed of tissue not normally present at site.
5. Some phakomatous lesions are neoplasms but majority are hamartomas or choristomas

Question 21

NF1

Answer 21

Question 22

Tuberous Sclerosis

Answer 22

Question 23

Sturge-Weber Syndrome

Answer 23

Question 24

Wyburn-Mason Syndrome

Answer 24

Question 25

Ataxia-Telangiectasis

Answer 25

Question 26

von Hippel-Lindau Disease

Answer 26

Question 27

Pregnancy and Neuro-ophthalmic Disorders

Answer 27

1. During pregnancy or post-partum period abnormalities can be exacerbated or occur with greater frequency → cerebral venous thrombosis, IIH, pituitary apoplexy, lymphocytic hypophysitis, preexisting pituitary macroadenomas, meningiomas and schwannomas as well as orbital or choroidal hemangiomas may undergo rapid expansion
2. CN 7 and CN 6 palsies due to increased interstitial fluid around optic nerve causing compression
3. Severe preeclampsia/eclampsia → serous RD, choroidal infarction, retinal vascular narrowing, retinal artery vasospasm/occlusion, PRES
4. Optic nerve swelling, ischemic optic neuropathy

Question 28

Posterior Reversible Encephalopathy Syndrome

Answer 28

1. Headache, AMS, seizures, blurry vision, homonymous visual field loss, cortical blindness, photopsias, visual hallucinations
2. MRI → vasogenic edema involving white matter of cerebral posterior regions especially parieto-occipital lobes however frontal, temporal lobes and basal ganglia and brainstem
3. Acute HTN, preeclampsia/eclampsia, immunosuppressive drugs (cyclosporine, tacrolimus), renal disease, sepsis, multiorgan dysfunction syndrome
4. Reversible and visual prognosis excellent

Question 29

Lymphocytic Hypophysitis

Answer 29

1. Neuroendocrine disorder characterized by autoimmune inflammation of pituitary gland with various degrees of pituitary dysfunction
2. Chiasmal field loss secondary to suprasellar extension, diplopia due to invasion of cavernous sinuses
3. Imaging and endocrine tests not specific
4. Suspect diagnosis in woman who is pregnant or in peripartum period who presents with headaches, bitemporal visual field loss, changes in 1 or more pituitary hormones.
5. Steroids and other immunosuppressive drugs may be required

Question 30

Vertebrobasilar System Disease

Answer 30

1. Posterior circulation composed of vertebral, basilar and posterior cerebral arteries that supply occipital cortex, brainstem, cerebellum
2. Nonophthalmic symptoms
   
   1. ataxia, imbalance or staggering
   2. vertigo + deafness or vomiting (brainstem)
   3. transient dysarthria and dysphagia
   4. hemiparesis, hemiplegia, hemisensory disturbances
   5. drop attacks → suddenly falls to ground with no warning or LOC
3. Bilateral blurring or dimming of vision occurs as frequently as vertigo. Sudden bilateral graying or whiting out of vision with episodes of lasting seconds to minutes and may be accompanied by flickering or flashing stars. Photopsias may occur mimicking scintillating scotomas of migraines. Attacks frequently repetitive. Migraine can produce similar symptoms with or without headaches
4. Homonymous visual field changes without neurological symptoms suggests involvement of posterior circulation → highly congruous homonymous visual field defects without systemic symptoms typical of occipital lobe infarcts
5. Patients reporting reading difficulties without obvious cause should undergo visual field and Amsler grid examination in search of centrally located visual field defects
6. Cerebral and cortical blindness caused by bilateral occipital lobe lesions → normally reactive pupils, unremarkable fundus, may deny blindness (Anton syndrome).
7. Ocular motor disturbances common and patient may report diplopia → horizontal or vertical gaze palsies, INO, skew deviation, nystagmus, ocular motor CN palsies
8. Etiologies
   
   1. Atheromatous occlusion, HTN, microembolization, fluctuations in cardiac output, arterial dissection, polycythemia, anemia, vasospasm, hypercoagulable states, congenital aplasia or hypoplasia of vertebral or posterior communicating artery, chiropractic manipulation, subclavian steel syndrome (reversal of blood flow in vertebral artery caused by occlusion of proximal occlusion of subclavian artery).
   2. MRA, CTA
   3. Carotid Doppler NOT sufficient
   4. Less likely to find vascular structural cause than with carotid disease. Should search for underlying disorders → HTN, HLD, DMT2, postural hypotension, 2D ECHO
   5. Tx → statins, antiplatelets, anticoagulants

Question 31

Cerebral Aneurysms

Answer 31

1. May be associated with HTN
2. Also associated with AVMs, coarctation of aorta, polycystic kidney disease, connective tissue disease, tobacco smoking
3. Ophthalmic artery aneurysm → progressive unilateral optic neuropathy
4. Anterior communicating artery aneurysm → loss of vision by compressing optic chiasm or tract
5. PCom and ICA junction aneurysm can cause ipsilateral CN3 palsy. CN3 complete with pupil involvement + CN3 partial with or without pupil involvement should raise concern for aneurysm
6. Intracavernous carotid artery aneurysm → cause cavernous sinus syndrome and may cause CN 3,4,5,6 palsies with facial pain
7. Ruptured aneurysm → severe headache, nausea, vomiting, neck stiffness, CN 6 palsy from elevated ICP, lethargy, comatose, disoriented. Ocular hemorrhage may be seen → intraretinal, preretinal, subhyaloid, vitreous, subconjuncitval, orbital, optic nerve sheath hemorrhage. Vitreous + SAH = Terson syndrome
8. CTA or MRA, CT for ruptured aneurysm. If CT negative with suspicion for SAH need LP or CTA to confirm presence of subarachnoid blood
9. Stabilizing treatment → lower BP. Definitive treatment → surgical clipping, stent coiling

Question 32

Arterial Dissection

Answer 32

1. Risk factors → trauma, cervical manipulation, connective tissue disorders, fibromuscular dysplasia
2. Clinical features variable.
3. ICA dissection → ipsilateral forehead pain, pain around orbit and neck. Ipsilateral ophthalmic signs with contralateral neurological deficits. Bruit may be present
4. Sometimes symptoms delayed weeks to months after trauma
5. Transient or permanent symptoms include amaurosis fugax, acute stroke, monocular vision loss, ipsilateral Horner syndrome. If dissection extends to intracranial ICA may see cranial nerve neuropathies
6. Vision loss from ICA dissection → from embolic occlusion of ophthalmic artery, CRAO, SPCA, retinal branch arteries. Rare cause of ocular ischemic syndrome
7. Vertebral and basilar arteries involved in 40% of cases
8. MRI diagnostic for extracranial ICA, CTA for vertebrobasilar system
9. Tx → anitplatelets, anticoagulants, stent
   10.

Question 33

Arteriovenous Malformations

Answer 33

1. Symptoms typically arise prior to 30 yo
2. Much more likely to become symptomatic before a hemorrhage occurs.
3. Seizures first manifestation in 30% of patients, 20% have headaches or other neurological deficits
4. Neuro-ophthalmic symptoms depends on location
5. Some patients report subjective intracranial bruit
6. Abnormal arterial communication with dural venous sinus may result in elevated venous pressure and elevated intracranial pressure
7. MRI best for unruptured AVMs

Question 34

Cerebral Venous Thrombosis

Answer 34

1. May present with headaches, papilledema, and may be confused with IIH
2. Pregnancy → lateral and superior sagittal sinuses commonly affected
3. Cavernous sinus thrombosis → septic form from infection of face, oral cavity, sphenoid or ethmoidal sinuses. Otitis media or orbital cellulitis a rare cause. May see headaches, nausea, vomiting, somnolence, fevers, chills, tachycardia, meningitis, sepsis. Orbital signs → lacrimation, orbital congestion, conjunctival edema, eyelid swelling, ptosis, proptosis, ophthalmoplegia, K anesthesia, facial numbness, Horner syndrome, venous stasis retinopathy. CN 6 palsy most consistent early neurologic sign. Septic CST emergency → early aggressive antibiotics and anticoagulation as an adjunctive therapy. Steroids may help reduce inflammation and edema
4. Aseptic CST → no evidence of infection, orbital congestion less severe. Anticoagulation and antiplatelet therapy often used
5. Gradenigo syndrome → Facial pain + CN 6 palsy = lateral sinus thrombosis. May see increased ICP
6. Superior sagittal sinus thrombosis → consider in atypical IIH in skinny women and men
7. Neuroimaging required to diagnose. MRV or CTV.
8. Prothombotic conditions most commonly protein C and S deficiency, antiphospholipid, anti-cardiolipin, factor 5 leiden, hyperhomocysteinemia, prothrombin mutation. Other predisposing factors → pregnancy, OCPs, cancer, facial infections, inflammatory disease, hematologic disease
9. Tx → towards underlying medical condition, anticoagulants, elevated ICP medications

Question 35

Reversible Cerebral Vasoconstriction Syndrome

Answer 35

1. Severe recurrent headaches, with or without focal neurological deficits, and/or seizures, and segmental constriction of cerebral arteries that resolves within 3 months
2. Light sensitivity, blurred vision, hemianopic VF loss
3. 1/2 cases occur during postpartum period of after exposure to vasoactive substances → SSRIs, triptans, amphetamines, nasal decongestants, ergotamine, cannabis
4. May lead to ischemic stroke or SAH even though benign
5. MRA → string of beads appearance of cerebral vessels
6. Ca+ channel blockers treatment

Question 36

HIV

Answer 36

1. CN palsies most likely CN 7
2. Optic neuropathy 2/2 demyelination may be seen
3. HIV-associated neuroretinal disorder → apparent normal DFE with subtle optic nerve and retinal abnormalities: thinner RNFL, subtle loss of color vision, VF defects,

Question 37

Cytomegalovirus

Answer 37

1. Seen in patients with HIV
2. Anterior optic nerve infection produces acute loss of vision and swelling
3. Brainstem involvement → diplopia, ptosis, INO, CN palsies, gaze palsies, ptosis
4. Clinical diagnosis, PCR of CSF may help

Question 38

Progressive Multifocal Leukoencephalopathy

Answer 38

1. Reported in patients with MS treated with natalizumab
2. Due to JC virus that infects oligodendrocytes
3. Behavioral and cognitive abnormalities common
4. MRI shows parieto-occipital white matter changes causing range of neuro-ophthalmic dysfunctions