Third ventricular tumors.

Because of the uncertainty of a histological diagnosis without biopsy in tumors which lie within the third ventricle, we have advocated a surgical exploration of all cases. Those located in the posterior third ventricular or pineal region present a special problem and have been discussed elsewhere. Tumors lying in anterior portions of the third ventricle have been approached through a transcallosal route which we have preferred over the transfrontal route for the reasons indicated. The approach is relatively simple and associated with low morbidity. Problems have been encountered from forceful retraction of the anterior sagittal sinus which has resulted in deficits of frontal lobe function and with injury to both fornices or the septal region which has resulted in akinetic mutism. Fortunately, these complications are rare.