STEREOTAXIC PALLIDOTOMY FOR THE TREATMENT OF PARKINSONS-DISEASE - EFFICACY AND ADVERSE-EFFECTS AT 6 MONTHS IN 26 PATIENTS

We evaluated the safety and efficacy of microelectrode-guided stereota ctic pallidotomy in patients with advanced Parkinson's disease (PD). U sing diagnostic criteria and evaluations outlined in the Core Assessme nt Programme in Transplantation (CAPIT) protocol, we studied unilatera l pallidotomy in 26 patients with advanced idiophatic PD, motor fluctu ations, and peak dose dyskinesias. All underwent unilateral stereotact ic pallidotomy. Assessments conducted in the ''practically defined off '' and ''best on'' states at baseline and at 1 and 6 months postoperat ively included Unified Parkinson's Disease Rating Scale (UPDRS) parts II, III, and IV and timed motor testing as outlined in CAPIT. Motor UP DRS in the ''off'' state improved at 1 and 6 months after surgery (p = 0.002, p = 0.008) Likewise, the sum of individual ''off'' contralater al motor UPDRS items improved (p = 0.0002, p = 0.0005). The duration ( p = 0.0001 at 1 and p = 0.001 at 6 months) and severity (p = 0.003 at 1 and p = 0.0005 at 6 months) of dyskinesia improved, but; other aspec ts of the ''on'' function were unchanged. Serious adverse effects occu rred in eight patients and included one fatal deep and three nonfatal frontal lobe hemorrhages with resultant language or behavioral deficit s. Nonhemorrhagic complications included one hemiparesis and three fro ntal lobe syndromes. Pallidotomy improves PD motor disability in the ' 'off'' state. Peak dose dyskinesias are reduced, although other aspect s of ''on'' motor function are unchanged. Although morbidity may limit its use, pallidotomy is effective in targeting particular symptoms su ch as unremitting dyskinesia and severe ''off'' motor disability in ad vanced PD.