CONTRALATERAL TRANSCONDYLAR APPROACH FOR ANEURYSMS OF THE POSTERIOR INFERIOR CEREBELLAR ARTERY VERTEBRAL ARTERY COMPLEX

We report a patient with an aneurysm of the left vertebral artery (VA) -posterior inferior cerebellar artery (PICA) complex that was treated successfully via a contralateral transcondylar approach, The aneurysm was small, pointed laterally to the right, and was located across the midline just above the level of the foramen magnum, This unusual locat ion required special consideration during diagnostic evaluation and su rgical planning, To simulate the operative view, the patient's head wa s turned 45 degrees, This extreme oblique view offered useful informat ion with respect to the choice of side from which the surgical approac h should be made, Removal of the posteromedial part of the occipital c ondyle allowed us to clip the aneurysmal neck without difficulty altho ugh the surgical approach was made on the side contralateral to the pa rent artery, We conclude that the contralateral approach for VA-PICA a neurysms should be considered when aneurysms cross the midline, and th at extradural removal of the basal bony structures, including the occi pital condyle, can provide a wide working space without excessive retr action on the brain stem. (C) Pearson Professional 1996.