Functional neurosurgery with the Leksell Gamma knife.

Sixty patients underwent a total of 64 separate Gamma Knife radiosurgical procedures for treatment of a variety of functional disorders between July 1992 and February 1995. Thirty-four patients with intractable pain received unilateral (32 patients) or bilateral (2 patients) lesions in the intralaminar thalamus. Twenty-nine patients with facial pain, including 19 with typical trigeminal neuralgia. 8 with facial pain due to tumors involving the trigeminal nerve and 2 with other forms of facial pain, were also treated. Five patients with Parkinson's disease underwent pallidotomy (2) or thalamotomy (3) with the Gamma Knife and 2 patients with non-Parkinson's tremor were also treated with gamma-thalamotomy. The rate of improvement or resolution of the functional disorders was similar to that seen with other forms of surgical therapy. No immediate complications were seen, but 4 patients who underwent thalamotomy for pain developed delayed transient complications and 1 death was seen following bilateral thalamotomy.