1. The III nerve palsy: when to panic UBC Clinical neuroophthalmology day - 18 November 2005 Jason Barton ?

2. III nerve palsiesidiopathic (21%) trauma (13%) neoplasm (11%) aneurysm (16%) vascular (23%) other (14%) Adult III nerve palsies (n= 1432) idiopathic (35%) trauma (25%) neoplasm (11%) aneurysm (2%) vascular (8%) other (10%) inflammation (8%) Pediatric III nerve palsies (n = 97) 3. Nuclear III palsy: bilateral superior rectus weakness, bilateral ptosis, bilateral pupil paresis 4. 39 year old man with HIV/AIDS, presenting with headache and bilateral ptosis. Exam showed limited downgaze od more than os, and bilateral ptosis. Autopsy showed HIV encephalitis surrounding the aqueduct. 5. Fascicular III palsy: may mimic divisional palsies, monocular elevation paresis, or isolated paresis of the pupil or inferior oblique ipsilateral limb ataxia (brachium conjunctivum) contralateral resting tremor/chorea/ballismus (red nucleus) contralateral paresis of the limbs and/or face (cerebral peduncle) vertical supranuclear palsy (riMLF, inC) drowsiness Causes of midbrain III syndromes: vascular 'top of the basilar' syndromes. intrinsic primary or secondary tumors infections (AIDS, TB) demyelination brainstem hemorrhages (including uncal herniation) 6. Bilateral fascicular III palsies 68 year old man with hypertension, awoke with bilateral ptosis. Exam: 0% elevation and 0% depression ou, 50% adduction od and 0% adduction os. Severe ptosis: 6mm lid fissure od and 4mm os, with frontalis contraction. Pupils 4mm od and 2.5mm os, with light reaction. Left leg paresis. MRI with DWI 7. Peripheral III palsy: subarachnoid portion contralateral hemiparesis. Meningismus depending on etiology. Causes: Aneurysms: basilar or ICA-pcomm artery Ischemia: hypertension/DM. sildenafil/cocaine, GCA, carotid occlusion. Trauma: LOC or skull fractures, uncal herniation Tumors: neurinomas and schwannomas Inflammation: Lyme, sarcoidosis - rare. 8. Complete III palsy with ICA-pcomm aneurysm 9. Woman anticoagulated for atrial fibrillation with right temporal lobe and capsular stroke, returned 1 year later with new right III palsy. 1.5 years later, showed signs of aberrant regeneration also (elevation accompanied by adduction). 10. Peripheral III palsy: Cavernous sinus lesions: divisional paresis IV V and VI, but can cause III mononeuropathies. Causes: Vascular: dural arteriovenous malformations, giant ICA aneurysm Tumours: 1 - meningioma, chordoma, craniopharyngioma, 2 - nasopharyngeal ca Vascular/tumour: pituitary apoplexy ! Inflammation: viral or flu-like infections, sphenoid sinusitis 11. Woman with known metastatic breast cancer 12. Aneurysms: basilar or ICA-pcommA aneurysms: usually acute painful palsy. Natural history - Soni, JNNP 1974 rupture of ICA-PCA aneurysms preceded by warning sign 70% of time. average time between initial symptoms and subarachnoid hemorrhage = 30 days. delay in treating ICA-PCA aneurysm increases mortality from 20% to 67%. 13. Best way to detect an aneurysm? (Can we avoid 1-2% risks of formal angiography?) CTA and MRA detect aneurysms of 4-5mm. Is that good enough ? -Yanaka et al, Neurosurg 2003: aneurysms of 4-8mm can present with III palsy -Jacobson & Trobe, AJO 1999: MRA would miss < 1.5% of aneurysms with III palsy Is the prognosis of small ICA-PCA aneurysms with III palsy better than large ones? For asymptomatic aneurysms, risk of SAH size and location. NEJM 2004: