Long-term results of ventrolateral thalamotomy for patients with Parkinson's disease

This study evaluated the long-term outcome for 53 patients with idiopathic Parkinson's disease treated by stereotactic thalamotomy between 1977 and 1996 at our institute. Significant reduction of tremor and rigidity of the contralateral extremities persisted throughout the follow-up period (mean 8.8 years) in 44 patients who underwent unilateral thalamotomy. These effects resulted in postoperative improvement of activity of daily life (ADL) with reduced dosage of levodopa. The effect of surgery on akinesia was limited and postoperative progression of akinesia was related to the postoperative deterioration of ADL. Multivariate analysis disclosed that the preoperative akinesia score was the critical factor for poor outcome. Nine patients underwent bilateral thalamotomies at a mean interval of 56 months. Five patients were obviously benefited from the second thalamotomy. The only perioperative complication was large intracerebral hematoma at the lesion site in one patient. This study confirmed the reliable and persistent effect of thalamotomy. Patients with Parkinson's disease whose disability is mainly caused by tremor and/or rigidity will be benefited from this procedure. Second thalamotomy, contralateral to the initial side, may be indicated if the ADL deteriorates due to the progression of the symptoms on the non-treated side. Patients disabled by advanced akinesia are not good candidates for thalamotomy.