Stroke

Chapter 1. Transient Monocular Visual loss (TMVL) D. Eric Searls Temporary loss of vision in one eye is a common presentation with a broad differential diagnosis. Embolism from the heart, aorta, and ipsilateral carotid artery and migraine-related retinal artery vasoconstriction are the most frequent causes. Chapter 2. Cerebellar infarction Louis R. CaplanThe diagnosis of cerebellar infarction is often difficult. Gait ataxia is the most important finding. Large pseudo-tumoral cerebellar infarcts can be life-threatening. The most common causes are embolism from the heart and proximal vertebral artery.Chapter 3. Lateral medullary infarction Louis R. CaplanThe classic symptoms and signs of infarction of the lateral medulla are extremely important to recognize. The usual cause is occlusion of the intracranial portion of the vertebral artery but occasional patients can develop the syndrome by occluding a penetrating artery branch to the medulla.Chapter 4. Intracranial arterial stenosis Adele Al-HazzaniThe epidemiology, and findings in patients with stenosis of intracranial large arteries are different than those present in patients with occlusive disease of the brain-supplying arteries in the neck. Middle cerebral artery stenosis is the most common artery involved.Chapter 5. Dissection of the Internal Carotid Artery in the neck Louis R. CaplanDissections usually involve the pharyngeal portion of the artery and often present with headache and local pain. Dissections through the intima-media portion of the artery frequently cause brain ischemia and infarction. Dissections through the media-adventitia often cause aneurysmal dilatation and are accompanied by Horner's syndrome, pulsatile tinnitus, and sometimes involvement of the lower cranial nerves as they exit from the skull. Chapter 6. Intracranial carotid artery dissection Louis R. Caplan Intracranial arterial dissections are much less common than extracranial and more often cause brain infarction. Rupture through the adventitia can cause subarachnoid hemorrhage. Chapter 7. Posterior cerebral artery territory infarction caused by dissection of the vertebral artery in the neck Louis R. CaplanPosterior cerebral artery territory infarction usually presents as an isolated homonymous hemianopia. The most common cause is embolism from the neck or intracranial portions of the vertebral artery or the heart. Neck pain is a frequent finding in neck vertebral artery dissections.Chapter 8. Pure motor lacunar stroke Magdy Selim Lacunar brain infarction is caused by intrinsic disease of penetrating arteries or plaques within the parent artery that impede flow through the penetrating artery branches. The diagnosis is important to make since treatment differs from occlusion of large arteries and brain embolism.Chapter 9. Polar artery territory thalamic infarct Louis R. CaplanSmall penetrating artery territory infarcts can sometimes cause a dramatic change in cognitive function and behavior. Infarction in the antero-medial portion of the thalamus in the territory of the tuberothalamic (polar) artery causes decreased initiative, lack of spontaneity and diminished behavior. The symptoms and signs improve after months.Chapter 10. Basilar artery occlusive disease Sandeep KumarAtherosclerotic occlusive disease of the basilar artery causes pontine ischemia. Transient ischemic attacks often precede more persistent ischemia. The symptoms and signs are often diagnostic and include motor and oculomotor dysfunction. Chapter 11. Embolism to the top-of-the- basilar artery Louis R. Caplan Emboli that reach the intracranial posterior circulation arteries often travel to the distal bifurcation of the basilar artery causing ischemia in the distribution of the penetrating arteries that supplying the paramedian midbrain and thalami. Characteristic signs include hypersomnolence, dysmemory, and vertical gaze palsies.Chapter 12. Binswanger disease Louis R. CaplanThe most common vascular dementing illness in the world is due to multiple small deep infarcts accompanied by extensive white matter loss and demyelination. This condition, first described by Otto Binswanger is caused by disease of penetrating arteries, most often due to chronic hypertension.Chapter 13. Subarachnoid hemorrhage Richard P. GoddeauAlthough there are multiple potential causes of bleeding into the subarachnoid space, rupture of an intracranial aneurysm is by far the most important. Recognition of the typical syndrome and identification of the bleeding lesion must be accomplished quickly and accurately. Rebleeding and vasoconstriction are the most important complications.Chapter 14. Lobar hemorrhage in Cerebral Amyloid Angiopathy Richard P. GoddeauCerebral amyloid angiopathy is a very common condition among geriatric patients. Hemorrhage ensues from breakage of fragile amyloid-laden arteries and arterioles predominantly in the grey-white matter junction regions and the pial surface. Bleeds are often lobar and can be accompanied by white matter ischemic lesions.Chapter 15. Dural sinus venous thrombosis Adele Al-Hazzani Cerebral venous thromboses share many of the same risk factors as venous occlusions in the remainder of the body. Headache, seizures, and focal neurological signs dominate the presenting findings. The prognosis is good when patients are treated with anticoagulants.Chapter 16. Reversible cerebral vasoconstriction syndrome Louis R. CaplanProtracted multifocal narrowing and dilatation of intracranial arteries, usually referred to as Reversible Cerebral Vasoconstriction Syndrome (RCVS) is common, many times more often encountered than cerebral vasculitis. Women are affected more often than men and the post-partum and early menopausal periods are frequent times of onset. The onset is often abrupt with a so-called "thunderclap" severe headache and headaches recur in the days and weeks after onset.Chapter 17. Reversible posterior encephalopathy syndrome Louis R. Caplan Brain edema most often in the posterior portions of the cerebral hemispheres develops in a variety of situations (including: pre-ecclampsia and ecclampsia, hypertensive encephalopathy, the immunosuppressive drugs cyclosporine and tacrolimus, pheochromocytoma, acute glomerulonephritis, Reversible Cerebral Vasoconstriction Syndromes (RCVS), and acute endocrinopathies) and is often referred to as the Posterior Reversible Encephalopathy Syndrome (PRES). The most common clinical findings are: agitation, hyperactivity, loss of vision, visual hallucinations, and seizures.Chapter 18. Atrial fibrillation-related brain embolism Sandeep Kumar Atrial fibrillation is the most common cause of embolism to the brain from the heart. A dilated left atrium and ventricular and valvular cardiac abnormalities increase the likelihood of embolism. Chapter 19. Management of the patient with acute brain ischemia Adele Al-HazzaniAcute brain ischemia is an emergency. Rapid evaluation and treatment are needed to save viable brain tissue. Imaging of the brain and its vascular supply are key to decisions related to the benefits and risks of reperfusion.Chapter 20. Patent Foramen Ovale - paradoxical embolism Louis R. CaplanParadoxical embolism, arising from thrombi in the leg or pelvic veins, and passing through a patent foramen ovale to reach the left ventricle of the heart and subsequently the brain has become an increasingly important cause of stroke. However, as many as 25-30% of individuals have a PFO and this common cardiac finding is often unrelated to the cause of the patient's brain ischemia.Chapter 21. Arterial dolichoectasia with pontine infarction D. Eric SearlsElongated and dilated arteries (Dolichoectasia) may be congenital or atherosclerotic. Dolichoectasia causes ischemic strokes, hemorrhagic strokes, cranial nerve signs, brainstem compression, and hydrocephalus. Potential mechanisms for ischemic stroke include hemodynamic, intraluminal thrombus compromising blood flow in branch arteries, artery-to-artery embolism, small vessel ischemic disease, and arterial dissection.Chapter 22. Arterio-venous malformations Gayle Rebovich Arterio-venous malformations s are characterized by direct arterial- venous connections and may include aneurysms. The most common presenting findings are: headache, seizures, and hemorrhage. Risk factors for subsequent hemorrhage include hemorrhage on presentation, older age, deep venous drainage pattern, deep brain location, and associated aneurysms.Chapter 23. Cavernous angiomas Magdy Selim Cavernomas are abnormal clusters of sinusoidal capillaries embedded in normal brain tissue. The most frequent associated symptom in patients with cavernomas is seizures. Hemorrhage can be recurrent but blood is usually contained within the capsule of the lesion.Chapter 24. Post cardiac surgery encephalopathy and stroke Louis R. CaplanThe most common cause of strokes and encephalopathy after coronary artery bypass surgery is embolization from atherosclerotic aortic atheromas. A thorough evaluation including a history of transient ischemic attacks and strokes, and studies of cardiac function and aortic atherosclerosis should precede elective coronary artery bypass surgery. Strategies for surgery- on-pump vs off pump, and management of the aorta should be planned before surgery.Chapter 25. Bacterial endocarditis Richard P. GoddeauBacterial and fungal vegetations on cardiac valves and cardiac endothelium can be the source for systemic (e.g. splenic or renal) as well as cerebral emboli and infarction. Anticoagulation is usually not indicated in endocarditis complicated by stroke. Treatment is with antimicrobials.Chapter 26. Coexistent severe coronary and carotid artery disease Ennis Duffis Most patients with asymptomatic carotid artery stenosis undergoing CABG are not at increased risk of perioperative stroke. The most common mechanism of perioperative stroke in patients with carotid stenosis is embolism from the heart or aorta. Only rare strokes are caused by hypoperfusion. Routine revascularization of patients with carotid stenosis is not warranted in patients undergoing CABG as it exposes the patient to the risks associated with two procedures.Index