[Transoral transclival approach to vertebral-posterior inferior cerebellar artery aneurysm. Case report].

A 61-year-old male was hospitalized for subarachnoid hemorrhage. Cerebral angiography revealed a small left vertebral-posterior inferior cerebellar artery aneurysm, 5 mm to the right of the midline and in the lower third level of the clivus--the so-called "no man's land." It was felt that surgery through the lateral suboccipital approach would likely result in neurological deficits, since the aneurysm would be obscured by the tortuous parent artery or the basilar artery. Therefore, the transoral transclival approach was undertaken and the aneurysm was successfully obliterated. Postoperatively, the patient developed transient right hemiparesis and mild meningitis without evidence of liquorrhea, but fully recovered with conservative management. Certain specific sites of aneurysms, as well as excessive tortuosity of the parent artery, are considered to be indications for the transoral transclival approach. Meningitis is the most worrisome complication of this approach, and mortality is high. Effective preventative measures, which were taken in this case, include tight closure of the dura mater and the pharyngeal mucous membrane, use of the smallest possible clip, and continuous cerebrospinal fluid drainage.