Intracranial aneurysm

Vascular phenomena, major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, and Janeway s lesions... 

The main clinical indications for imaging the cerebral circulation are TIA (e.g. to identify arterial stenosis), acute ischemic stroke (e.g. to identify vessel occlusion), intracerebral hemorrhage (e.g. to identify an underlying vascular malformation) and possible arterial dissection, flbromuscular dysplasia or other arteriopathies, cerebral aneurysm, intracranial venous thrombosis or cerebral vasculitis. 

Thrombolytic dru are contraindicated in patients with known hypersensitivity, active bleeding, history of stroke, aneurysm, and recent intracranial surgery. 

EC-IC arterial bypass involves the use of general anesthesia, open craniotomy, and end-to-side anastomosis of the superficial temporal artery to a branch of the middle cerebral artery (MCA) (Fig. 6.1). Currently, this technique is being used primarily in the setting of intracranial aneurysm therapy, moyamoya disease, and... 

Endo S, Nishijima M, Nomura H, Takaku A, Okada E. A pathological study of intracranial posterior circulation dissecting aneurysms with subarachnoid hemorrhage report of three autopsied cases and review of the literature. Neurosurgery 1993 33 732-738. 

Known arteriovenous malformation, aneurysm, or intracranial neoplasm... 

Hemorrhagic strokes account for 12% of strokes and include subarachnoid hemorrhage, intracerebral hemorrhage, and subdural hematomas. Subarachnoid hemorrhage may result from trauma or rupture of an intracranial aneurysm or arteriovenous malformation. Intracerebral hemorrhage occurs when a ruptured blood vessel within the brain parenchyma causes formation of a hematoma. Subdural hematomas are most often caused by trauma. 

In subarachnoid hemorrhage due to a ruptured intracranial aneurysm or arteriovenous malformation, surgical intervention to clip or ablate the vascular abnormality substantially reduces mortality from rebleeding. The benefits of surgery are less well documented in cases of primary intracerebral hemorrhage. In patients with intracerebral hematomas, insertion of an intraventricular drain with monitoring of intracranial pressure is... 

History of intracranial hemorrhage, arteriovenous malformation, or aneurysm... 

The ACE gene encodes two isozymes (somatic ACE isozyme and germinal ACE isozyme). ACE is a membrane-bound enzyme on the surface of vascular endothelial cells that also circulates in plasma and shows great individual variability determined by an I/D polymorphism in intron 16 of the ACE gene (ACE-I/D polymorphism). More than 160 ACE polymorphisms have been reported, 34 of which are located in coding regions, and 18 are missense mutations (606). ACE-related polymorphic variants have been associated with hypertension, atherosclerosis, stroke, left ventricular hypertrophy, chronic renal failure in IgA nephropathy, Henoch-Schonlein purpura nephritis, mechanical efficiency of skeletal muscle, intracranial aneurysms, susceptibility to myocardial infarction, diabetic nephropathy, AD, and longevity (12,606,607). 

Contraindications Active internal bleeding, arteriovenous malformation or aneurysm, cerebrovascular accident (CVA) with residual neurologic defect, history of CVA (within the past 2 yr) or oral anticoagulant use within the past 7 days unless PT is less than 1.2 X control, history of vasculitis, hypersensitivity to murine proteins, intracranial neoplasm, prior IV dextran use before or during percutaneous transluminal coronary angioplasty (PTCA), recent surgery or trauma (within the past 6 wk), recent (within the past 6 wk or less) GI or GU bleeding, thrombocytopenia (less than 100,000 cells/pl), and severe uncontrolled hypertension... 

Contraindications Active internal bleeding, AV malformation or aneurysm, bleeding diathesis, intracranial neoplasm, intracranial orintraspinal surgery or trauma, recent (within past 2 mo) cerebrovascular accident, severe uncontrolled hypertension... 

Contraindications Active internal bleeding or a history of bleeding diathesis within previous 30 days, arteriovenous malformation or aneurysm, history of intracranial hemorrhage, history of thrombocytopenia after prior exposure to tirofiban, intracranial neoplasm, major surgical procedure within previous 30 days, severe hypertension, stroke... 

Atherosclerosis mainly affects large- and mediumsized arteries. Extracranial manifestations at the carotid bifurcation statistically dominate the intracranial arteries. Besides typical manifestations at the carotid siphon or the vertebrobasilar junction, atherosclerosis is occasionally also found in peripheral intracranial vessel segments. Typical sequelae of atherosclerosis are stenosing plaque formations, ulcerations, dilatations or the evolution of fusiform aneurysms, which can be accompanied by extensive formation of thrombus. 

Schievink WI, Puumala MR, Meyer FB et al. (1996) Giant intracranial aneurysm and fibromuscular dysplasia in an adolescent with alpha 1 -antitrypsin deficiency. J Neurosurg 85 503-506... 

Hindman B. J., Todd M. M., Gelb A. W., et al. (1999) Mild hypothermia as a protective therapy during intracranial aneurysm surgery a randomized prospective pilot trial. Neurosurgery 44, 23-32. 

Oyesiku NM, Colohan AR, Barrow DL, Reisner A. Cocaine-induced aneurysmal rupture an emergent negative factor in the natural history of intracranial aneurysms Neurosurgery 1993 32(4) 518-26. 

Intracranial dissection is much rarer. It may present with subarachnoid hemorrhage owing to rupture of a pseudo-aneurysm, as well as with ischemic stroke, and is less often diagnosed during life (Farrell et al. 1985 de Bray et al. 1997 Chaves et al. 2002). 

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