Morbidity and mortality following pallidotomy in Parkinson's disease: a systematic review.

Objective: To study the frequency of morbidity and mortality associated with pallidotomy.

Method: The authors searched the MEDLINE electronic database for pallidotomy articles reported between January 1992 and December 2000. They selected studies by the following criteria: original clinical data, unequivocal description of morbidity and mortality, and unselected consecutive cases. The authors extracted the following data: number of patients, unilateral or bilateral procedures, age, localization technique, follow-up time, number of patients with adverse effects, number of patients with permanent adverse effects (>3 months), types of adverse effects, and mortality.

Results: For unilateral pallidotomy, 12 prospective studies included 334 patients. Of these patients, 30.2% (95% CI, 25.3 to 35.2) had adverse effects, and 13.8% (95% CI, 10.1 to 17.5) had permanent adverse effects. A symptomatic infarction or hemorrhage occurred in 3.9% (95% CI, 2.1 to 6.6). The mortality rate was 1.2% (95% CI, 0.3 to 3.0). In the series with microelectrode recording, the frequency of adverse effects was 14.4% (95% CI, 4.7 to 24.1) higher and the frequency of stroke was 4.9% (95% CI, 1.4 to 8.4) higher. The most frequent adverse effects were problems with speech (11.1%) and facial paresis (8.4%). For bilateral pallidotomy, five historical cohort studies including 20 patients were available for review. Fourteen patients had an adverse effect, and the most frequent adverse effects were impairments of speech and cognition.

Conclusions: The risk of permanent adverse effects associated with unilateral pallidotomy was 13.8%. A symptomatic infarction or hemorrhage occurred in 3.9% of patients, and the associated mortality rate was 1.2%.