Arteriovenous malformations intracranial

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... 

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 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... 

A 13-year-old boy underwent a 17-hour craniotomy in an attempt to resect an arteriovenous malformation with propofol-based anesthesia. He developed frank propofol infusion syndrome after 74 hours of postoperative propofol sedation in the neurosurgical ICU (used to manage intracranial hypertension). Echocardiography showed severe biventricular dysfunction despite extraordinary pharmacological support. Extracorporeal circulation with membrane oxygenation (ECMO) was instituted at the bedside via cannulation of the left femoral vessels. Hemofiltration... 

Moyamoya seems to be mainly confined to the Japanese and other Asians, and in most cases the cause is unknown (Bruno et al. 1988 Chiu et al. 1998). Some cases are familial (Kitahara et al. 1979) others appear to be caused by a generalized fibrous disorder of arteries (Aoyagi et al. 1996), and a few may result from a congenital hypoplastic anomaly affecting arteries at the base of the brain, or associated with Down s syndrome (Cramer et al. 1996). The syndrome may present in infancy with recurrent episodes of cerebral ischemia and infarction, mental retardation, headache, epileptic seizures and, occasionally, involuntary movements. In adults, subarachnoid or primary intracerebral hemorrhage are also common owing to rupture of collateral vessels. There have also been a few reports of associated intracranial aneurysms (Iwama et al. 1997) and also of cerebral arteriovenous malformations. 

Arteriovenous malformations present most commonly with signs consistent with a space-occupying lesion or seizures and consist of an abnormal fistulous connection(s) between one or more hypertrophied feeding arteries and dilated draining veins (Clatterbuck et al. 2005) (Fig. 7.5). The blood supply is derived from one cerebral artery or, more often, several, sometimes with a contribution from branches of the external carotid artery. Arteriovenous malformations vary from a few millimeters to several centimeters in diameter. Approximately 15% are associated with aneurysms on their feeding arteries. Some grow during life but a few shrink or even disappear, and some are multiple. These fistulae occur in or on the brain, or in the dura of the intracranial sinuses. 

Telangiectasias are collections of dilated capillaries that are usually of no clinical significance (Milandre et al. 1987). They may be associated with hereditary hemorrhagic telangiectasia (the Osler-Weber-Rendu syndrome), but this is more likely to be associated with neurological complications from a pulmonary arteriovenous malformation with right-to-left shunting, such as cerebral hypoxia, brain abscess, paradoxical and septic embolism, or from an associated intracranial arteriovenous malformation or aneurysm (McDonald et al. 1998). 

Active internal bleeding, history of CVA, recent intracranial or intraspinal surgery or trauma, intracranial neoplasm, arteriovenous malformation or aneurysm, bleeding diathesis or severe uncontrolled hypertension (increases risk of bleeding)... 

AVM arteriovenous malformations BP blood pressure CTA CT angiography D50 50% dextrose EKG electrocardiogram i.a. intra-arterial 7C//intracranial hemorrhage i.v. intravenous M7myocardial infarction PCP primary care physician 7Tprothrombin time PTT partial thromboplastin time rt-PA recombinant tissue plasminogen activator SAH subarachnoid hemorrhage... 

Abstract This chapter focuses on the vascular applications of injectable biomatetials. Two clinically relevant vascular conditions, cerebral arteriovenous malformations and intracranial aneurysm, will be discussed in terms of endovascular embolization. This chapter then outlines available embolic materials used to treat each condition, as well as highlighting new injectable biomaterials developed for embolization purposes. 

For further information about intracranial aneurysms, arteriovenous malformations, endovascular embolization techniques, and interventional neuroradiology, see the books listed below. 

Velat, G. J., Reavey-CantweU, J. F., Sistrom, C., Smullen, D., Fautheree, G. L., Whiting, J., Lewis, S. B., Mericle, R. A., Fitment, C. S. Hoh, B. L. (2008) Comparison of n-butyl cyanoacrylate and ONYX for the embolization of intracranial arteriovenous malformations analysis of fluoroscopy and procedure times. Neurosurgery, 63, ONS75-ONS82. 

Weber, W., Kis, B., Siekmann, R., Jans, P., Laumer, R. Kuhne, D. (2007) Preoperative embolization of intracranial arteriovenous malformations with Onyx. Neurosurgery, 61, 244-254. 

Figure 4.13 Intracranial arteriovenous malformation (AVM) and a radiological view before and after embolisation, visualised by the presence or absence of a contrast agent.

Autopsy data showed that only 12% of AVMs become symptomatic during life (The Arteriovenous Malformation Study Group 1999), and intracranial hemorrhage is the most common clinical presentation (Al-Shahi and Warlow 2001 Hofmeister et al. 2000 The Arteriovenous Malformation Study Group 1999). 

On the basis of retrospective analysis, the rupture of brain AVMs is estimated to be less severe than that of intracranial aneurysms, with mortality between 10% and 15% and an overall morbidity of less than 50% (The Arteriovenous Malformation Study Group 1999). Hemorrhages of brain AVMs are subarachnoidal (30%), parenchymal (23%), intraventricular (16%), and in combined locations in 31% of cases (Hartmann et al. 1998). Parenchymal hemorrhages were most likely to result in a neurological deficit (52%). Overall, in the series of Hartmann et al. (1998), 47% of patients... 

Al-Shahi R, Warlow C (2001) A systematic review of the frequency and prognosis of arteriovenous malformations of the brain in adults. Brain 124 1900-1926 Amin-Hanjani S, Robertzon R, Arginteanu MS, Scott RM (1998) Familial intracranial arteriovenous malformations. Case report and review of the literature. Pediatr Neurosurg 29 208-213... 

Aoki Y, Nakasawa K, Tago M et al. (1996) Clinical evaluation of Gamma knife radiosurgery for intracranial arteriovenous malformations. Radiat Med 14 265-268 Aoki S, Sasaki Y, Machida T et al. (1998) 3D-CT angiography of cerebral arteriovenous malformations. Radiat Med 16 263-271... 

Bank WO, Kerber CW, Cromwell LD (1981) Treatment of intracerebral arteriovenous malformations with isobutyl 2-cyanoacrylate initial experience. Radiology 31 1 Barnett GH, Little JR, Ebrahim ZY, Jones SC, Friel HT (1987) Cerebral circulation during arteriovenous malformation operation. Neurosurgery 20 836-842 Batjer HH, Suss RA, Samson D (1986) Intracranial arteriovenous malformations associated with aneurysms. Neurosurgery 18 29-35... 

Batjer HH, Devous MD Sr, Meyer YJ, Purdy PD, Samson DS (1988) Cerebrovascular hemodynamics in arteriovenous malformation complicated by normal perfusion pressure breakthrough. Neurosurgery 22 503-509 Batjer HH, Devous MD Sr, Seihert GB et al. (1989a) Intracranial arteriovenous malformation relationship between clinical factors and surgical complications. Neurosurgery 24 75-79... 

Batjer HH, Purdy PD, Giller CA, Samson DS (1989h) Evidence of redistribution of cerebral blood flow during treatment for an intracranial arteriovenous malformation. Neurosurgery 25 599-605... 

Brown RD, Wiebers DO, Forbes G et al. (1988) The natural history of unruptured intracranial arteriovenous malformations. J Neurosurg 68 352-357 Brown RD, Wiebers DO, Forbes GS (1990) Unruptured intracranial aneurysms and arteriovenous malformations and relationship of lesions. J Neurosurg 73 859-863 Brown RD Jr, Wiebers DO, Torner JC, O Fallon WM (1996a) Incidence and prevalence of intracranial vascular malformations in Olmsted County, Minnesota, 1965 to 1992. Neurology 46 949-952... 

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