=====Small basal outpouching=====

Small basal [[outpouching]] is the most common angiographic configuration suggesting a basal rupture.

The occurrence of small basal outpouchings was determined in the initial angiographic examinations of 471 patients with a ruptured aneurysm. Information was also obtained from patient charts, surgical and interventional reports, operative video records, and reviews of radiological investigations.

A small basal outpouching was identified in 41 (8.7%) of the 471 ruptured aneurysms. In the surgical series (n = 286), a basal rupture was identified in 8 (30.8%) of the 26 cases of a basal outpouching and successfully treated by aneurysm clip placement. In the endovascular series (n = 185), intraprocedural aneurysm rebleeding developed in 5 of the 15 patients (33.3%) with a basal outpouching, which was most commonly observed with anterior communicating artery aneurysms.

The current surgical series included a 9% incidence of ruptured intracranial aneurysms with a small basal outpouching, and a 31% incidence of these basal outpouchings being identified as the rupture point. The results also suggested that endovascular coiling of a basal outpouching carries a high risk of intraprocedural aneurysm rebleeding, whereas surgical clipping is safer and provides more protection against rebleeding of aneurysms with a basal rupture
((Park J, Woo H, Kang DH, Kim Y, Baik SK. Ruptured intracranial aneurysms with
small basal outpouching: incidence of basal rupture and results of surgical and
endovascular treatments. Neurosurgery. 2012 Nov;71(5):994-1001; discussion 1002. 
doi: 10.1227/NEU.0b013e31826cde9f. PubMed PMID: 22895399.)).