Vasospastic reactions in response to the transsylvian approach

Cerebral vasospasm may occur with various neurosurgical procedures such as the treatment of intracranial aneurysms or of skull base tumors. This study was designed to provide more insight into the nature of vasospastic reactions in response to surgical manipulation alone.

Twenty patients who underwent selective amygdalohippocampectomy for medically intractable epilepsy using the transsylvian approach were studied prospectively. Transcranial Doppler ultrasound (TCD) was used for examination of blood flow velocities within the basal cerebral arteries before and after the operation.

Three types of vascular reactions were observed: 1) No or only minimal reaction with increase of the blood flow velocities less than 50% as compared with the preoperative baseline values (N = 4); 2) Ipsilateral/bilateral increase of the blood flow velocities more than 50% of the baselines (N = 14); 3) Paradoxic reactions such as early postoperative resistance flow and contralateral rise of the blood flow velocities (N = 2). There was no morbidity or mortality in this series.

The transsylvian approach is associated with significant changes in hemodynamics--partially caused by mechanical manipulation and partially by the degradation of blood--although the risk of neurological deterioration seems to be low.