An orbitocranial approach to complex aneurysms of the anterior circulation.

A surgical approach to the skull base was developed in cadavers and then used in the treatment of patients with complex aneurysms of the anterior circulation. The operative method involves removal of portions of the orbital rim, orbital roof, and sphenoid bone. By removing the orbital rim and a portion of the orbital roof, multidirectional viewing is possible. This is important when dealing with the anterior aspect of the cavernous sinus and anterior clinoid process, as must frequently be done when isolating the neck of an ophthalmic aneurysm. The optic canal is opened wide and the optic nerve mobilized, allowing resection of the dura propria covering the cavernous carotid artery. Clip placement is performed in an anteroposterior plane, thus lessening the chance for compromise of the internal carotid artery. The low approach alleviates brain retraction and the small flap minimizes brain exposure. The approach also allows preservation of the arterial and neural supply to the frontalis and temporalis muscles, thereby preventing postoperative cosmetic deficits. During the past year and a half, this approach has been employed in 25 patients with difficult aneurysms of the anterior circulation. The difficulties of these cases stemmed from their odd location, size, or complex anatomy. Although periorbital edema may have been more severe during the first postoperative week, overall improved cosmesis was achieved.