Stereotactic radiosurgery under local anesthesia with the Leksell Gamma Knife can effectively treat some patients with recurrent tic douloureux after unsuccessful medical/surgical procedures. Seven of 12 patients have shown complete relief or improvement of their trigeminal neuralgia. No complications have been observed.

The Leksell Gamma Knife is a useful and safe method to perform thalamotomy and pallidotomy in selected older patients with Parkinson''s disease and related movement disorders. In this preliminary report, 2 of 3 patients with severe intention tremor were relieved of their symptoms by thalamotomy, as were 4 of 7 patients with Parkinson''s tremor. Four of 8 patients had significant improvement of contralateral rigidity following pallidotomy.

Aggressive radiation therapy for the management of inoperable lung cancer has increased tumor control and survival. However, approximately 20% of patients continue to experience local recurrence as the sole manifestation of treatment failure. Seven hundred thirty-four patients were initially treated by radiation therapy for inoperable lung cancer, for recurrence after resection, or as adjunct postoperative therapy. Twenty-nine patients were referred for retreatment of cancer that recurred within the original treatment field. Following retreatment, 14 of 29 patients (48%) had a favorable subjective response, and 20 of 27 patients (74%) a favorable objective response. A favorable response was observed for all cell types and over a wide range of retreatment dosages. Symptomatic radiation pneumonitis developed in one patient, rib sclerosis and fracture developed in another. Th median survival after onset of retreatment was five months with a range of one month to 54 months. The clinically determined mechanisms of death were persistent intrathoracic disease in 14 of 25 patients (56%), intrathoracic disease and distant metastasis in 7 of 25 (28%), distant metastasis in 3 of 25 (12%), and unknown in 1 of 25 (4%).

Fifteen patients were treated in the Gamma Knife Unit and followed for 18 months or longer. Four patients had Cushing''s disease, 4 had acromegaly, 3 had Nelson''s syndrome and 3 had prolactinomas. One patient had no endocrinopathy. One of the patients with acromegaly and 2 of those with prolactinomas had been operated prior to Gamma Knife treatment. Radiological tumor localization was not an insuperable problem in this series. The effect of Gamma Knife treatment on the anterior pituitary neoplasia, as such, was consistently successful. All the tumors which received 10 Gy or more to the edge showed either a reduction in volume or at least cessation of growth. On the other hand, the effect of the treatment was less consistent in respect to the endocrinopathies. These results are discussed in respect of dose and tumor size. It is suggested that the role of the Gamma Knife in the treatment of pituitary adenomas requires further clarification, based on prospective studies.