Stereotactic biopsy of intracranial space occupying lesions.

The results of stereotactic biopsies of intracranial expanding lesions with narrow instruments both prior to and during the CT era are evaluated in 345 patients. Eighty-four cystic lesions were needled and roughly classified. Small, cystic, or solid tumours in anatomically well-defined areas such as the sellar, the third ventricle, and the pineal regions were as easily punctured and classified without as with CT scanning. When larger tumours in different compartments were punctured the biopsy verification rate increased from 55% towards 91% if an enhanced CT investigation was included. A stereotactic biopsy is a fairly safe procedure, yielding in this series a mortality less than 1% and a morbidity of 2.3%.