NEUR 7510 Neurology Clerkship

1. NEUR 7510Neurology Clerkship

2. Session 2:Spells

3. Definitions • Stroke: sudden loss of brain function due to blockage or rupture of a blood vessel; alternatively an acute brain related event (focal/generalized) • Embolic stroke: blockage of a vessel from a proximal source • Thrombotic stroke: in situ obstruction of blood flow resulting in ischemia • Lacunar infarction: small vessel related ischemic stroke • Hemorrhagic infarction: bleeding into the brain and damaging brain tissue

7. Or

10. Carotid artery disease • Atherosclerosis is common at the bifurcation of the common carotid artery • Stenosis of the internal carotid artery is a potentially treatable cause of: • Ischaemic stroke • Transient ischaemic attack • Retinal infarction • A patient with an asymptomatic 50% carotid stenosis has 1-2% per year risk of a stroke • The risk of stroke increases with the degree of stenosis • Once a stenosis has become symptomatic the risk of a stroke is further increased • Once an ischaemic stroke has occurred the risk of further stroke is ~10% in the first year and ~5% in subsequent years Assessment of stenosis • Carotid bruits are an unreliable guide to severity of stenosis • May be absent in patients with severe stenosis

11. Intra-arterial angiography is the traditional method of assessing degree of stenosis 4% risk of inducing further neurological event 1% risk of permanent stroke Duplex ultrasound Doppler recordings allow assessment of flow at stenosis Also allows imaging of arterial anatomy

19. Lacunar infarct: This 52-year-old man with a history of poorly controlled hypertension presented with right body numbness. Examination was significant for a blood pressure of 182/96 mm Hg, retinal arterio-venous nicking and right-sided hemibody hypesthesia to pinprick and temperature sensation. The T2-weighted axial image on the left shows an area of high signal intensity within the left thalamus. The corresponding diffusion-weighted MR image on the right shows an isolated area of high signal intensity within the left thalamus.

21. What nonvascular processes mimic stroke?

22. Brain MRIs Contrasting Bell's Palsy with a Central Pontine Infarct Gilden, D. H. N Engl J Med 2004;351:1323-1331

23. 100 patients with cerebrovascular disease • Subarachnoid hemorrhage (5%)? • Intraparenchymal hemorrhage (20%)? • Ischemia (75%)?

24. 100 patients with cerebral ischemia • 25% Large vessel atherothromboembolism • 25% Small vessel disease • 25% Cardioembolism • 5% Other conditions • 20% Unknown

25. Types of brain hemorrhage • Intraparenchymal • Often hypertensive • Amyloid angiopathy • Into a tumor • Trauma related • Underlying vascular abnormality • Subarachnoid • Trauma • Related to an aneurysm • Subdural • Chronic versus acute; often related to trauma or bleeding propensity • Epidural • Acute often related to trauma and injury to middle meningeal artery

26. Coup and contre-coup Epidural hematoma Subdural hematoma Injury TRAUMA AND THE BRAIN Intraparenchymal hematoma Diffuse axonal injury

27. In what four locations do spontaneous (hypertensive) intracerebral hemorrhages most commonly occur? • Basal Ganglia • Putamen - Contralateral hemiparesis, contralateral sensory loss, contralateral conjugate gaze paresis, homonymous hemianopia, aphasia, neglect, or apraxia • Caudate nucleus - Contralateral hemiparesis, contralateral conjugate gaze paresis, or confusion • Thalamus - Contralateral sensory loss, contralateral hemiparesis, gaze paresis, homonymous hemianopia, miosis, aphasia, or confusion • Brain stem (typically pons)- Quadriparesis, facial weakness, decreased level of consciousness, gaze paresis, ocular bobbing, miosis, or autonomic instability • Cerebellum- Ataxia, usually beginning in the trunk, ipsilateral facial weakness, ipsilateral sensory loss, gaze paresis, skew deviation, miosis, or decreased level of consciousness • Lobar - Contralateral hemiparesis or sensory loss, contralateral conjugate gaze paresis, homonymous hemianopia, abulia, aphasia, neglect, or apraxia Putamen (50%); thalamus (25%); pons/brainstem (10%); cerebellum (10%), and cerebral hemispheres (5%)

31. 64 yo RH Woman • 5 min right arm weakness • 2nd episode involved the leg • What is the most likely anatomic localization?

33. Exam: • AV nicking • Rt cervical bruit • Right facial weakness • Rt pronator drift w/ slow ffm & 4/5 wrist ext • Rt leg weakness • Rt toe: upgoing • Account for the • forehead symmetry • absence of sensory findings • good grip strength in the face of very slow finger tapping • symmetric reflexes • History reveals long-standing hypertension, MI 3 yrs prior, long • Tobacco use and rx for a diuretic • Pathological process • Mechanisms of injury

34. What is the patient was 30 yo?

35. Tests Diagnostic studies: which are needed • Coagulation studies • Drug/tox screen • Genetic studies/cholesterol/glucose/other • ECG/Rhythm monitoring • ECHO (TTE/TEE) • Arch study • Arteries: carotid ultrasound/CTA/MRA • 4 vessel angiography • Brain CT/MRI/MRA/MRV/CTV

37. Management • Preventive therapy? • Blood pressure • Smoking • Blood sugar • Cholesterol • Exercise • Medications • Prevent complications? • Aid in recovery? • Risk factors? • Preventable? • Present management • TPA • Coumadin • Antiplatelet

38. Medical management • Stop smoking • Pharmacological treatment of hypertension and diabetes • Prophylactic aspirin • Asprin prevents around 40 ‘vascular events’ per 1000 patients treated for 3 years • It should be started at 175-150 mg daily once ischaemic stroke confirmed by CT • It should also be given to those with asymptomatic stenoses • The combination of aspirin and dipyridamole is no more effective than aspirin alone.

39. Surgery for symptomatic stenosis North American Symptomatic Carotid Endarterectomy Trial (NASCET) • Compared endarterectomy plus medical treatment in those patients with • Non-disabling stroke in 4-6 months prior to surgery • Severe (70-99%) ipsilateral stenosis • The risk of stroke or death over 2 years was reduced (9% vs. 26%) in surgery group • 5.8% randomised to surgery had stroke within 30 days • Benefit also seen in those with more than 50% stenosis but not to same degree European Carotid Surgery Trial (ECST) • ECST risk of stroke or death over 3 years was reduced (12% vs. 22%) in surgery group • 7.5% randomised to surgery had stroke or died within 30 days of operation • In those with mild (0-30%) and moderate (30-60%) symptomatic stenoses there was benefit from surgery • Overall, In those with symptomatic stenoses • Best results are seen in those with more severe stenosis • Benefit only seen in institutions with low perioperative stroke and death rate • Surgery indicated in those with severe stenosis (more than 70%) that have recently become symptomatic • Operation should be performed by experienced surgeon • Centres should audit their results and have a perioperative stroke rate of less than 7% • Angina and hypertension should be well controlled pre-operatively • If patient selection is poor or complication rate high then there will be no benefit from surgery.  Carotid angioplasty • Angioplasty (± stent placement) is being used to dilate stenoses • No published randomised trials • In uncontrolled studies severe stenoses (more than 70%) have been dilated to less than 50% • Re-stenosis often occurs and a significant risk of stroke during the procedure

40. Surgery for asymptomatic stenosis Asymptomatic Carotid Atherosclerosis Study • 1662 patients with more than 60% reduction in luminal diameter • Randomised to either: • Endarterectomy + medical treatment (aspirin 300 mg) • Medical treatment alone • Risk of ipsilateral stroke over 5 year period was reduced (5% vs. 11%) in surgery group • 2.3% in surgery group had stroke within 30 days of surgery • 0.4% in medical group had stroke in same time period • Overall, benefit for those with asymptomatic stenosis but only the presence of a low perioperative complication rate. Asymptomatic Carotid Surgery Trial • 3120 patients with more than 60% reduction in luminal diameter • Randomised to either immediate or deferred carotid surgery • Risk of stroke within 30 days of surgery was 3.1% • Risk of stroke over 5 year period was reduced (3.8% vs. 11%) in surgery group • Results were similar to ACAS study

41. 58 yo LH Man • 10 minute episode • LUE tingling • Within a minute spread to face & leg • LUE & LLE would not work • Anatomical localization? • Exam • Bruits: femoral, subclavian arteries • Does the normal examination help or hurt the presumed localization?

42. Questions • Differential of transient focal neurologic dysfunction and distinguishing features • Long-term prognosis of a transient ischemic attack (TIA)? • Admission required?

43. 81 yo M • Acute onset of vertigo and nausea • Rt leg unsteady & Rt facial numbness • Anatomical localization? Hoarse Eyes move rapidly to Lt then slowly to Rt Rt pupil 2 mm with ptosis; Lt pupil 4 mm Rt face: reduced pp & temp Palate pulls to Lt RUE & RLE dysmetria LUE & LLE decreased pp & temp

44. Eye movements: Nystagmus • Defining central and peripheral vertigo • Differentiating central vs. peripheral vertigo • Diagnosis of this patient • Mechanism? • Treatment? • What are the cause & treatment of isolated vertigo attacks? • What if there was left hearing loss and facial weakness? • What it evolved slowly?

46. MRI Right Inferior Cerebellar Infarction in a Man with Acute Vertigo, Vomiting, Nystagmus Elicited by Right, Left, or Upward Gaze, and Severe Gait Instability. . Axial T2-weighted image shows a high-intensity signal (white) in the right inferior cerebellum, with displacement of the medulla. Neurosurgical intervention was required because of brain-stem compression with noncommunicating hydrocephalus and progressive deterioration in mental status. On the day after surgery, the patient's mental status rapidly improved. Over the next week, his nystagmus resolved and he began walking. The inset illustrates the vascular supply to the inferior cerebellum. The inferior cerebellum is perfused by the medial and lateral branches of the posterior inferior cerebellar artery (PICA) and the anterior inferior cerebellar artery (AICA).7,8 Hotson, J. R. et al. N Engl J Med 1998;339:680-685

48. Dix-Halpike Test in BPV

49. Treatment of BPV

50. Schematic Drawing of Peripheral and Central Vestibular Nystagmus with and without Visual Fixation. Hotson, J. R. et al. N Engl J Med 1998;339:680-685