Abstract
Two patients with an aneurysm of vertebro-basilar (VB) junction were operated by“transpetrosal approach”. Both patients were hospitalized having the symptoms of subarachnoid hemorrhage, and angiography showed a saccular VB junction aneurysm directed toward the brainstem. Subtemporal craniotomy was made above the external meatus, and upper rim of the anterior part of pyramid bone was drilled extradurally. Small dural incisions were made above and below the superior petrosal sinus, and tentorium was incised 1 cm in length after clipping of the petrosal sinus. The aneurysm was visualized without retraction of the brainstem, and it was clipped between Vth and VIIth cranial nerves through this bone defect. The first patient had VIIth and VIIIth cranial nerve palsy postoperatively due to careless opening of internal meatus. The second patient had no neurological deficit except for transient VIth cranial nerve palsy. Complete clipping of the aneurysm was confirmed by postoperative angiography in both cases.
The characteristic point of this method is to avoid the retraction damage of the temporal lobe or brainstem, which is considered to be hazardous in the patient operated through the subtemporal or the suboccipital route.
