Stereotactic CT scan applied to stereotactic thalamotomy and biopsy.

A stereotactic method to visualize deep subcortical structures through which the electrode would pass intraoperatively is described in detail. The procedures are: Approximation of the tentative target point in the lateral craniogram according to some craniometric data. Determination of the invading route and its transfer to the patient's scalp. CT scanning by a new generation scanner to distinguish between gray and white matter along the predetermined plane. Intraoperative adjustment of the electrode to the predetermined CT image and error correction. Verification by recording electrical activities in subcortical tissue. This simple method would be of great benefit for the accurate and safe performance of stereotactic thalamotomy and biopsy.