Transcerebellar biopsy in the posterior fossa: 12 years experience.

Utilizing the Leksell stereotactic system, the transcerebellar approach was used for posterior fossa biopsies. During a period of 12 years, a total of 29 patients were operated on by this technique, among them 12 children. In the adult, the procedure was carried out with the patient awake and sitting upright; the pediatric patients required general anesthesia and the head was supported either manually or by a clamp. Representative specimens were obtained in all cases but one, showing a wide diagnostic spectrum. As a rule, the procedures were performed smoothly, with no serious side effects. Stereotactic biopsies in the posterior fossa, hitherto seldom performed, open new diagnostic perspectives, one of which is for use in obscure brain stem lesions. The transcerebellar approach has been proven to be easy, direct, and safe provided an appropriate technique is used, such as that described in the present paper.