Abstract
1. Craniocerebral reference points and the width and height of the third ventricle were measured in intraoparative positive pressure pneumovetriculograms on 71 patients who underwent stereotaxic surgery for various reasons. 2. When reference points were located on two-dimensional plane in relation to the anterior comissure, distant reference points were more variable than those close to the anterior comissure. 3. The CA-CP distance and the width of the third ventricle were 22.9±1.9 and 8.1±2.3 mm (mean±S. D.) respectively and the mean values of the width and height of the third ventricle and the CA - CP distance were greater in males than in females respectivery. 4. A correlation coefficient was high between the width of the third ventricle and the CA-CP distance, but was low between the width and height of the third ventricle and between the height of the ventricle and the CA-CP distance.
