RESUMO
In contrast to aneurysms of the middle cerebral artery at the bifurcation, aneurysms at the origin of the lenticulostriate arteries (LSA) are uncommon. Six surgically treated patients (34 to 70 year-old; 3 men, 3 women) were reviewed. 5 patients presented with subarachnoid hemorrhage (H&H grade 2:3, 3:1, 4:1; Fisher type 2:1, 3:3, 4:1) and 2 patients had multiple aneurysms. All aneurysms arose from the postero-superior surface of the M1. Although neck clipping was achieved in every patient, re-application of the clip was necessary during surgery in 3 patients because the tip of the blade extended to the other perforators that ran parallel to the M1. Results were as follows: GR 3, MD1, SD 1, D1. Apart from a 70 year-old patient who died of vasospasm (H & H 4), fair results in two patients were accompanied by ischemic complications of the LSA. All 3 patients who required re-application of the clip during surgery showed a lacunar infarct of perforating arteries on post-operative CT. Special care of perforating arteries not only around the neck (the LSA) but also behind the aneurysm is essential for successful neck-clipping of aneurysms at this location.