UNASSIGNED: OBJECT Hemorrhagic origin is unidentifiable in 10%-20% of @entity1 presenting with spontaneous @entity510 ( @entity510 ). While the @entity1 in such cases do well clinically, there is a lack of long-term angiographic followup. The authors of the present study evaluated the long-term clinical and angiographic follow-up of a @entity1 cohort with @entity510 of unknown origin that had been enrolled in the Barrow @entity1756 Trial (BRAT). METHODS The BRAT database was searched for @entity1 with @entity510 of unknown origin despite having undergone two or more angiographic studies as well as MRI of the brain and cervical spine. Follow-up was available at 6 months and 1 and 3 years after treatment. Analysis included demographic details, clinical outcome (Glasgow Outcome Scale, modified Rankin Scale [mRS]), and repeat vascular imaging. RESULTS @entity510 of unknown etiology was identified in 57 (11.9%) of the 472 @entity1 enrolled in the BRAT study between March 2003 and January 2007. The mean age for this group was 51 years, and 40 members (70%) of the group were female. Sixteen of 56 @entity1 (28.6%) required placement of an external ventricular drain for @entity1276 , and 4 of these subsequently required a ventriculoperitoneal shunt. Delayed @entity2806 occurred in 4 @entity1 (7%), leading to @entity64 in one of them. There were no rebleeding events. Eleven @entity1 were lost to followup, and one @entity1 died of unrelated causes. At the 3-year follow-up, 4 (9.1%) of 44 @entity1 had a poor outcome ( @entity5329 ), and @entity531 , which was available in 33 @entity1 , was negative. CONCLUSIONS @entity1276 and delayed @entity2806 , while infrequent, do occur in @entity510 of unknown origin. Long-term neurological outcomes are generally good. A thorough evaluation to rule out an etiology of @entity548 is necessary; however, imaging beyond 6 weeks from ictus has little utility, and rebleeding is unexpected.

XXXX of unknown origin: hospital course and long-term clinical and angiographic follow-up.

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity64 :: ('MESH:D020521', 'Disease') :: ['stroke'] @entity5329 :: ('380836(Tax:10090)', 'Gene') :: ['mRS > 2'] @entity1276 :: ('MESH:D006849', 'Disease') :: ['hydrocephalus', 'Hydrocephalus'] @entity2806 :: ('MESH:D002545', 'Disease') :: ['cerebral ischemia'] @entity510 :: ('MESH:D013345', 'Disease') :: ['SAH', 'Subarachnoid hemorrhage', 'subarachnoid hemorrhage'] @entity548 :: ('MESH:D006470', 'Disease') :: ['hemorrhage'] @entity531 :: ('MESH:D013901', 'Disease') :: ['neurovascular imaging'] @entity1756 :: ('MESH:D017542', 'Disease') :: ['Ruptured Aneurysm']
@entity510 :: (MESH:D013345,Disease) :: ['Spontaneous subarachnoid hemorrhage']
