Posteroventral medial pallidotomy in levodopa-unresponsive parkinsonism.
BACKGROUND: Parkinsonism in a 42-year-old patient, which was presumably related to peripheral trauma, did not respond to levodopa therapy. OBSERVATION: We treated the patient with microelectrode-guided unilateral posteroventral medial pallidotomy and followed up with magnetic resonance imaging and prospective clinical evaluation. Pallidotomy resulted in marked improvement of right-sided parkinsonian symptoms and functional disability at 4.5 months after surgery. Microelectrode recording during pallidotomy revealed discharge patterns that were similar to those seen in patients with Parkinson disease. Postoperative magnetic resonance imaging confirmed the location of the lesion in the posteroventral medial pallidum. CONCLUSIONS: Posteroventral pallidotomy usually has limited benefit in patients with degenerative atypical parkinsonism who do not respond to levodopa therapy. Nevertheless, pallidotomy can be an effective treatment for other levodopa-unresponsive parkinsonian disorders.