Surgical treatment of the distal anterior cerebral artery aneurysms.

A series of eleven patients with aneurysms of distal anterior cerebral artery, microsurgically operated and submitted to accurate neuropsychological testing, is reviewed. Of these, ten patients had an aneurysm at the bifurcation of distal ACA into pericallosal and callosomarginal branches and only one patient had an aneurysm at the beginning of the fronto-polar artery. All our patients were operated by an interhemispheric approach, that was associated in 3 cases to a pterional approach in order to clip a second aneurysm in other location. The postoperative grade was satisfactory in any of the eleven patients. The aneurysms of distal ACA may be surgically obliterated through a variety of approaches but the exposure via the interhemispheric fissure is used by many neurosurgeons. In our experience the interhemispheric approach allows the exposure of feeding artery and the control of proximal vessel without morbidity. Some authors have modified the interhemispheric approach to improve, in their opinion, surgical exposure, introducing partial resection of anterior portion of corpus callosum, used, by them, especially for the aneurysms just beneath the genu of corpus callosum. Although resection of the anterior 2.5 cm of the corpus callosum can be performed without causing any neurological deficit, as reported by the same authors, the use of this technique might not be necessary. The present paper deals with current surgical techniques and their modification for the treatment of distal anterior cerebral artery (ACA) aneurysms.