Movement disorders stereotactic surgery for Parkinson's disease

Ablative stereotactic surgery improves manual performance time in Parkinson's disease

The objective of this study was to determine the influence of stereotactic ablative surgical interventions on the time required for the performance of manual tasks (i.e. performance time) in patients with Parkinson's disease (PD). We studied 28 patients after pallidotomy and pallido-thalamotomy who were evaluated at four time: before the operation, and 2 days, 3 and 6 months postoperatively. The speed of performance of handwriting and drawing were assessed by means of a chronometer using certain parts of an international standard scale (modified by Fahn). The patients were also assessed according to the Unified Parkinson's Disease Rating Scale (UPDRS) part III. The patients were divided into two groups. Those in group A had relief of all main Parkinsonian symptoms after pallidotomy including tremor. The patients in group B had no relief of tremor straight after pallidotomy. For them the pallidotomy was completed with thalamotomy in the same sitting, which had resulted in cessation of tremor. The time of performance of the manual tasks diminished significantly in all cases in both groups (Student's t-test: p<0.0001). No complications developed following pallidotomy. Pallido-thalamotomy caused transient adverse effects in two patients, and one patient developed permanent adverse effects such as dysarthria and dysequilibrium. Significant improvements were observed in the speed of handwriting and drawing in both groups, but pallido-thalamotomy was accompanied with complications.

Changes in vocal intensity in Parkinson's disease following pallidotomy surgery

The present study was designed to examine changes in vocal intensity following unilateral posteroventral pallidotomy (PVP) in a large sample of speakers with Parkinson's disease (PD) that exhibited a range of hypokinetic dysarthria. Twenty-five persons with PD were recorded using a variety of speech tasks, once prior to and once following PVP. The pre-PVP vocal SPL was subtracted from the post-PVP vocal SPL to derive a relative change in vocal SPL. Mildly dysarthric participants had significantly greater relative increases in vocal SPL following PVP than either moderately or severely dysarthric participants who had reduced vocal SPL following PVP. If future results follow those observed in the present data, mildly dysarthric Parkinson's patients may benefit most from unilateral PVP perhaps due to less overall destruction of the basal ganglia sensorimotor control circuits involved in oral facial functions, thus increasing the chances to observe improvements postsurgery.

Simultaneous bilateral pallidoansotomy for idiopathic dystonia musculorum deformans

A 17-year-old Russian male with a 9-year diagnosed history of dystonia musculorum deformans manifested as severe tortipelvis, lordosis, and axial and appendicular spastic dystonia, refractory to medical therapy, is reported. This patient underwent a simultaneous bilateral pallidoansotomy with dramatic results. Postoperative evaluation revealed sustained alleviation of all dystonic symptoms and abnormal movements. Rapid recovery of useful strength in all limbs as well as dramatic improvement in coordination occurred. Bilateral posteroventral pallidotomy and pallidoansotomy in the past have proven effective in alleviation of all parkinsonian symptoms, including dyskinesia and dystonia, without the concurrent risk of intransigent side effects associated with bilateral thalamotomy or other stereotactic surgical procedures. Pallidoansotomy may prove to be the treatment of choice for idiopathic torsion dystonia and merits further investigation.

The results, indications, and physiology of posteroventral pallidotomy for patients with Parkinson's disease

In the past, stereotactic surgical intervention for Parkinson's disease was considered indicated only in those patients with active motor manifestations that were refractory to pharmacological therapy, manifestations such as tremor, rigidity, dystonia, and dyskinesia. With the reintroduction and refinement of Leksell's posteroventral pallidotomy, both akinetic and hyperkinetic symptoms are now amenable to surgical treatment. We have analyzed the results of 126 patients who underwent either unilateral (n = 58) or bilateral (n = 68) posteroventral pallidotomies. The Unified Parkinson's Disease Rating Scale and Hoehn and Yahr Staging Scale were used for preoperative and postoperative objective assessments. Postoperative follow-up evaluation occurred initially at 1 week and subsequently at intervals between 1 and 12 months (mean = 4.5 months) after surgery. Although individual motor subscores on the Unified Parkinson's Disease Rating Scale were significantly reduced (n = 126, P < or = 0.01), the most dramatic findings were the reversal of akinetic symptoms and the elimination of dyskinesia and profound "off" periods. These clinical results, combined with intraoperative microelectrode records revealing pallidal neuronal hyperactivity, suggest a reconsideration of the pathophysiology of akinesia and point to possible mechanisms of akinesia improvement by posteroventral pallidotomy in some parkinsonian subgroups.