[Stereotactic applications in third ventricle tumors].

Stereotactic procedures are especially indicated for deep lesions within the brain substance, surrounded by functional structures, such as third ventricle tumors. Despite recent technological advances, the basis for stereotaxis remains minimally traumatic procedures, with the safety of vascular and ventricular anatomical definitions. Stereotactic procedures were performed in 63 patients of the national series. The indications, procedures, results and complications were reviewed. Stereotaxis was used with a diagnosis purpose in 34 patients. In all cases, the histological diagnosis was identified, which allowed the definition of the therapeutic strategy, and avoidance of useless direct approach to the third ventricle. Stereotaxis was used with a therapeutic purpose in 29 other patients : the procedure allowed the evacuation of colloid or glial tumor cysts, ventriculostomy, intracavitary irradiation, or radiosurgery. The stereotactic procedure should take in account the grade of associated hydrocephalus. Stereotactic evacuation of colloid cysts in this series (25 cases) often resulted in a recurrence of the cyst. Endoscopic procedures, eventually associated with stereotactic guidance, should be preferred for the treatment of colloid cysts.