Abstract
Twenty eight basilar-superior cerebellar aneurysms (BA-SCA) and 31 basilar bifurcation aneurysms (BA-BIF) in 57 patients were analysed in a radiometric study to determine the usefulness of the transsylvian approach. The line between the anterior clinoid process and the posterior clinoid process was adequate as a base line for measurement of aneurysmal location. The height of internal carotid bifurcation (ICAh) defined the entrance of the trans-sylvian approach. Postoperative complications such as oculomotor palsy or hemiparesis were less frequent when the ICAh was higher than 10 mm in both BA-SCA and BA-BIF. The height of the aneurysm (ANh) was another important factor which determined the difficulty of operation. Neurological deficits were less common when ANh was between 5 mm and 10 mm above the baseline. Simple radiometry offers an important clue as to the difficulty of operation.
Results of surgery was quite satisfactory and there was only one death in each (16 BA-SCA and 18 BA-BIF) that were treated by the trans-sylvian approach.
