Find The Lesion Info

Question 1

Myasthenia gravis

Answer 1

Autoimmune disease where the antibodies attack postsynaptic ACh receptors

Symptoms:

• Afebrile
• Fatigue
• Multiple episodes of double vision (usually first sign)
• Diplopia w/ lateral gaze
• dysphagia
• *muscles that are attacked first are ones with high levels of ACh receptors. Includes:
• ocular muscles
• soft palate muscles
• facial muscles

Treatment:

• Anticholinesterase agents (pyridostigmine is 1st line)
• IVIG/plasmapheresis (severe only)
• thymectomy (usually only if thymoma is present also)
• corticosteroids (can be added to pyridostigmine)

Question 2

Lateral medullary syndrome (Wallenberg syndrome)

Answer 2

• caused by a thrombotic ischemia of the posterior inferior cerebellar artery (PICA) (can be embolic but the symptoms would be rapid onset vs gradual which it usually is)*

Symptoms:

• double vision
• dizziness/vertigo
• drooping of the eyelids (usually unilateral)
• unilateral autonomic eye dysfunctions
• deviated uvula (away from affected side)
• hoarse voice
• dysdiadokinesia
• contralateral decreased pain sensation in the body
• ipsilateral Horner syndrome
• ipsilateral decreased overall sensation of the face

Treatment:

• tPA (if deemed suitable)
• thrombectomy
• need to get thrombus out*

Question 3

Idiopathic intercranial HTN (pseudotumor cerebri)

Answer 3

Unclear pathophysiology, expected to be increased CSF pressure

Symptoms:

• subacute severe headache (general not localized)
• blurred vision
• no nausea/vomiting
• bilateral papilledema/ optic disc edema
• no cranial nerve defects
• no cognitive disabilities
• no strength/ sensation or reflex abnormalities - no ocularmotor defects
• patient looks normal
• • lumbar puncture shows > 25cm opening pressure

common in females/obese patients/pregnant patients/ and HTN patients

Treatment:

• acetazolaminde (lower intercranial pressure)
• weight loss and eliminate over medication if needed
• CSF shunt of optic nerve sheath fenestrations (only if vision is threatened (patient complains of vision loss or pain with oculomotor movements))

Question 4

Aneurysmal 3rd nerve palsy

Answer 4

usually caused by a posterior communicating aneurysm impinging on the oculomotor nerve

Symptoms:

• ipsilateral dilated pupil and drooping of the eyelid
• diplopia
• “down and out” unilateral eye
• no headache*
• no other neurological defects*

**common in patients with a history of migraines/family history of aneurysm/ being female

Treatment:
- clipping or coiling of the aneurysm via surgery

Question 5

Optic chiasm lesions

Answer 5

Symptoms:

• severe headache (general not localized
• Bitemporal hemianopia (binocular vision)**
• NO papilledema
• flat and pale optic discs*