Extended lateral subtemporal approach for petroclival meningiomas: report of experience with 24 cases.

Subtemporal craniotomy centred on the external ear canal and its basal extension, involving resection of the roots of the zygomatic arch, roof of the external ear canal and superior third to half of the mastoid bone was used to treat surgically 24 meningiomas located in the petroclival region, having their maximum bulk at the level of tentorium. The approach was found to be suitable for dealing with middle fossa extensions of the tumour in addition to the part extending up to the mid-clivus or vertebrobasilar junctional region. The direction of the approach to the petroclival region was the shortest and most perpendicular from surface and avoided any neural or vascular exposure or manipulation. The basal exposure was horizontally wide and significantly low, which reduced the operating distance, limited the extent of temporal lobe retraction and provided additional space for manipulation of instruments. The exposure was manoeuverable with anterior, posterior and medial expansion being possible during or prior to tumour resection. The approach had the advantage of being simple and relatively quick, and of its familiarity to general neurosurgeons. The experience with the approach with petroclival meningiomas and its possible advantages over other available approaches to these lesions are analysed in this report.