[Aneurysms at the early branch of middle cerebral artery].

The cortical arteries arising from the proximal (Ml) segment of the middle cerebral artery (MCA) are called "early branches". We retrospectively analyzed clinical features in 10 patients with aneurysms located at the early branches of MCA. The incidence of these aneurysms was 9.5% among 95 MCA aneurysms. Patients consisted of 4 males and 6 females. Ages were 33-77 years old (average of 54.4). Four patients presented with subarachnoid hemorrhage (2 of them had intracerebral hematoma). The aneurysms were classified into 2 groups, the group of the early frontal branch (EFB: 7 cases) and the early temporal branch (ETB: 3 cases). All aneurysms were smaller than 6mm in diameter. The surgical treatment was performed through the pterional approach. Poor outcome occurred in 3 ruptured aneurysms of EFB (MD 1, SD 1, and D 1). At surgery, it is necessary to produce the working space by dissecting sylvian fissure sufficiently and to prevent ischemic complication by avoiding injury of the lenticulostriate arteries (LSA).