GAMMA-KNIFE PALLIDOTOMY - CASE-REPORT

We report a case of gamma knife pallidotomy resulting in a permanent c ontralateral homonymous hemianopsia and transient contralateral hemipa resis with some improvement in contralateral parkinsonian symptoms. Th is case illustrates the risk of gamma knife pallidotomy which preclude s physiologic target localization and can subject structures surroundi ng the target to a significant radiosurgical dose. Until noninvasive p hysiologic target localization is available gamma knife pallidotomy an d thalamotomy should be limited to patients with an unacceptably high risk for stereotactic percutaneous thermocoagulation.