Stereotactic pallidotomy and thalamotomy in the treatment of primary dystonia

BACKGROUND AND PURPOSE: The goal of the study was to assess the results of the stereotactic pallidotomy and thalamotomy in the treatment of primary dystonia. MATERIAL AND METHODS: Thirty patients with primary dystonia underwent twenty-eight stereotactic pallidotomies and twenty two thalamotomies. The operations were based on the fused images of computed tomography and magnetic resonance imaging, and were verified by an intraoperative neurophysiological investigation. Neurological and neuropsychological assessments were performed before surgery and at 3 days, 3 and 6 months after the operation. The Mann-Whitney U test was used to find out statistic differences between subgroups and the Wilcoxon test to compare results between particular assessments. RESULTS: The statistic analysis showed postsurgical amelioration of the neurological state lasting at least 6 months. A better long-term outcome was revealed in the subgroup of pallidotomies vs. thalamotomies, in the subgroup with the onset of dystonia after the age of 35 vs. earlier onset, and in the subgroup of the focal and local dystonia vs. generalized dystonia. The statistically significant improvement was achieved at a depression level and the statistically significant deterioration was not stated in the mental status after the operations. A very low percentage of neurological complications after the operations was found in the study. CONCLUSIONS: The stereotactic pallidotomies and thalamotomies are effective and safe options in the treatment of the intractable cases of primary dystonia. Both resulted predominantly in contralateral improvement of motor functions. However, the results of pallidotomies are better than thalamotomies six months after the surgery. The improvement of the mood without cognitive deterioration was revealed in the neuropsychological tests after the operations. Only few, persistent and mild complications were ascertained in the study.