Hiu Takeshi, Tsutsumi Keisuke, Kitagawa Naoki, Hayashi Kentaro, Ujifuku Kenta, Yasunaga Akio, Suyama Kazuhiko, Nagata Izumi
Department of Neurosurgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
Clin Neurol Neurosurg. 2009 Feb;111(2):216-9. doi: 10.1016/j.clineuro.2008.10.002. Epub 2008 Dec 5.
We herein report the first case of progressive perianeurysmal edema preceding the rupture of a small saccular aneurysm, without any intervention or intraluminal thrombosis. A 71-year-old woman was incidentally noted to have a cerebral aneurysm (5mm in diameter) at the lower basilar artery. Twelve months later, magnetic resonance (MR) imaging showed a T2-elongated area around a dome of the aneurysm buried in the brain stem, suggesting perianeurysmal edema formation. Interestingly, the edema progressed with the formation of a bleb, in addition to an increase in size of the aneurysm over the following 3-year period. The aneurysm eventually ruptured as a brain stem hemorrhage without any subarachnoid clots 3 days after the final check-up with MR imaging, by which a significant increase of edema formation with an increase in size of the aneurysm and a marked expansion of the bleb was observed. These findings raise the possibility that bleb formation and an enlargement of a small cerebral aneurysm might also be associated with perianeurysmal edema and a subsequent aneurysmal rupture. In addition to the pulsatile flow and/or compression from the expanded aneurysm, local inflammation in the aneurysm wall may play an important role in such edema formation.
