OBJECT: Certain @entity438 , because of their fusiform or complex wide-necked structure, giant size, or involvement with critical perforating or branch vessels. are unamenable to direct surgical clipping or endovascular coil treatment. Management of such lesions requires alternative or novel treatment strategies. Proximal and distal occlusion (trapping) is the most effective strategy. In lesions that cannot be trapped, alteration in blood flow to the "inflow zone," the site most vulnerable to @entity439 growth and @entity397 , is used. METHODS: From 1991 to 1999 the combined neurosurgical-neuroendovascular team at the Massachusetts General Hospital (MGH) managed 48 @entity438 that could not be clipped or occluded. Intracavernous internal carotid artery @entity439 were excluded from this analysis. By applying a previously described @entity1756 risk classification system (MGH Grades 0-5) based on the age of the @entity1 , @entity439 size, Hunt and Hess grade, Fisher grade, and whether the @entity439 was a @entity75 located in the posterior circulation, the authors found that a significant number of @entity1 were at moderate risk (MGH Grade 2; 31.3% of @entity1 ) and at high risk (MGH Grades 3 or 4; 22.9%) for treatment-related morbidity. The lesions were treated using a variety of strategies--surgical, endovascular, or a combination of modalities. @entity439 that could not be trapped or occluded were treated using a paradigm of flow alteration, with flow redirected from either native collateral networks or from a surgically performed vascular bypass. Overall clinical outcomes were determined using the Glasgow Outcome Scale (GOS). A GOS score of 5 or 4 was achieved in 77.1%, a GOS score of 3 or 2 in 8.3%, and @entity204 (GOS 1) occurred in 14.6% of the @entity1 . Procedure-related complications occurred in 27.1% of cases; the major morbidity rate was 6.3% and the mortality rate was 10.4%. Three @entity1 experienced aneurysmal @entity548 posttreatment; in two @entity1 this event proved to be fatal. @entity439 with MGH Grades 0, 1, 2, 3, and 4 were associated with favorable outcomes (GOS scores of 5 or 4) in 100%, 92.8%, 71.4%, 50%, and 0% of instances, respectively. CONCLUSIONS: Despite a high incidence of transient complications, @entity438 that cannot be clipped or occluded require alternative surgical and endovascular treatment strategies. In those @entity439 that cannot safely be trapped or occluded, one approach is the treatment strategy of flow alteration.

Combined surgical and endovascular techniques of flow alteration to treat fusiform and complex wide-necked XXXX that are unsuitable for clipping or coil embolization.

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity548 :: ('MESH:D006470', 'Disease') :: ['hemorrhage'] @entity438 :: ('MESH:D002532', 'Disease') :: ['intracranial aneurysms'] @entity75 :: ('MESH:D001927', 'Disease') :: ['giant lesion'] @entity397 :: ('MESH:D012421', 'Disease') :: ['rupture'] @entity439 :: ('MESH:D000783', 'Disease') :: ['aneurysms', 'aneurysm', 'Aneurysms'] @entity204 :: ('MESH:D003643', 'Disease') :: ['death'] @entity1756 :: ('MESH:D017542', 'Disease') :: ['aneurysm rupture']
@entity438 :: (MESH:D002532,Disease) :: ['intracranial aneurysms']
