Anatomical and microsurgical aspects of the carotid cave aneurysm

Introduction: The internal carotid artery in the clinoid segment is surrounded by two dural rings, proximal and distal. The proximal ring forms a firm collar around the artery and on microsurgical inspection, a small dural depression is often visualized at the point where the annulus surrounds the antero-medial aspect of the short and lower projection artery called the carotid cave. The presence of this space is variable, and can be found in up to 80% in an analysis of cadaveric specimens. This cave extends down the proximal dural ring and can approach the distal ring. Its exploration and microsurgical exposure is performed prior to cervical proximal control, anterior clinoidectomy with drill, canal and optic abutment, exposure of these rings, durotomy of both of them, complete release of the internal carotid clinoid segment for manipulation and free movement, exposure of the cave (shown in the video).

Discution: Carotid cave aneurysms, due to the anatomical complexity of this region and the need for detailed knowledge, are among the most difficult surgical approaches. The topographic diagnosis of these aneurysms at angiography is of paramount importance, where they can project medially and downwards pointing to the cave, invading the cavernous sinus or arising of the cave and directing superiorly.

Conclution: The choice of treatment depends on its intra or extradural extension. Faced with the potential risk of subarachnoid hemorrhage after rupture, we indicate a microsurgical treatment showing step by step the microsurgical anatomical aspects. The clipping option is made with fenestrated clips.