Abstract
To improve the safety of the treatment of unruptured aneurysms, the bypass technique is useful and sometimes necessary. Between 2004 and 2007, the first author treated 42 unruptured aneurysms, including 7 cases in which bypass was performed. In this article, we classify bypasses by purposes into 3 categories and explain each case. In the first category, the bypass is used as a substitute for the parent or daughter artery in conjunction with aneurysmal trapping or proximal ligation. In the second category, the bypass is used as an addition in cases in which atherosclerotic disease is concomitant with aneurysm. In the third category, the bypass is used for temporary revascularization for expected prolonged occlusion of the parent artery during aneurysmal clipping. All 3 of these uses of bypass can improve the safety of aneurysmal clipping by reducing ischemia if the bypass procedure itself is carefully performed.
