Randomized trial of pallidotomy versus medical therapy for Parkinson's disease

Thirty-six patients with Parkinson's disease (PD) were randomized to either medical therapy (N = 18) or unilateral GPi pallidotomy (N = 18). The primary outcome variable was the change in total Unified Parkinson's Disease Rating Scale (UPDRS) score at 6 months. Secondary outcome variables included subscores and individual parkinsonian symptoms as determined from the UPDRS. At the six month follow-up, patients receiving pallidotomy had a statistically significant reduction (32% decrease) in the total UPDRS score compared to those randomized to medical therapy (5% increase). Following surgery, patients' showed improvement in all the cardinal motor signs of PD including tremor, rigidity, bradykinesia, gait and balance. Drug-induced dyskinesias were also markedly improved. Although the greatest improvement occurred on the side contralateral to the lesion, significant ipsilateral improvement was also observed for bradykinesia, rigidity and drug-induced dyskinesias. A total of twenty patients have been followed for 2 years to assess the effect of time on clinical outcome. These patients have shown sustained improvement in the total UPDRS (p < 0.0001), "off" motor (p < 0.0001) and complications of therapy subscores (p < 0.0001). Sustained improvement was also seen for tremor, rigidity, bradykinesia, percent on time and drug-induced dyskinesias.     

Bilateral pallidotomy in Parkinson's disease: a retrospective study.

We evaluated the effects of bilateral pallidotomy in patients with advanced Parkinson's disease. Thirteen patients with Parkinson's disease had a staged bilateral pallidotomy if they had severe response fluctuations, dyskinesias, painful dystonia, or bradykinesia despite optimum pharmacological treatment. Assessment scales were the Unified Parkinson's Disease Rating scale (UPDRS), the Schwab and England scale, and a questionnaire on the effects of disability in activities of daily living and adverse effects. Postoperative magnetic resonance imaging was evaluated for lesion location and extension. The median off-phase UPDRS motor score was reduced from 43.5 to 29 after the first pallidotomy, and it was further reduced to 23.5 after the second pallidotomy (n = 8). The UPDRS activities of daily living off-phase score improved from 28.5 to 20.5 after the first pallidotomy and to 19 after the second pallidotomy (n = 6). The Schwab and England scale off-phase score showed an improvement after both procedures, first from 40 to 60, and thereafter to 90 (n = 8). On-phase dyskinesias were reduced substantially. Eight patients had adverse effects, of whom five had problems with speech. One patient became hemiplegic due to a delayed infarction. Ten patients experienced further benefit from the second procedure. Bilateral pallidotomy reduces dyskinesias. A second contralateral pallidotomy may reduce parkinsonism, although to a lesser degree compared with the first pallidotomy and with an increased risk for adverse effects.     

Effects of pallidotomy and levodopa on walking and reaching movements in Parkinson's disease.

We examined the effects of levodopa and unilateral pallidotomy on quantitative measures of walking and reaching in Parkinson's disease (PD). We also compared quantitative measures of movement with standard clinical rating scales. We used kinematic measures and the Unified Parkinson's Disease Rating Scale (UPDRS) motor subscale (subscale III) to evaluate the movement of 10 people with PD. Subjects were tested after withholding PD medications for at least 8 hours and again 30 to 45 minutes after taking the first morning dose of levodopa. They were studied in this manner before unilateral pallidotomy and then 3.5 to 10 months after surgery. The UPDRS motor subscale was performed in each state. Kinematic data were collected as subjects reached to a target and walked. The UPDRS motor subscale ratings were similar to those reported in the literature: pallidotomy improved the overall motor score and the contralateral bradykinesia + rigidity score, but not the gait + posture score. In contrast, kinematic measures demonstrated that levodopa and pallidotomy had different effects on walking and reaching speed. Both treatments improved walking speed, and the effect was additive. Levodopa improved reaching speed before pallidotomy but did not improve it as much after pallidotomy. Additionally, pallidotomy had inconsistent effects on reaching; some subjects were faster and others were slower. The subjects who initially reached more slowly improved after pallidotomy; the subjects who initially reached more normally (faster) worsened after pallidotomy. On the basis of our results, we speculate that basal ganglia output pathways that control walking and reaching may be distinct, such that bilateral projections to the pedunculopontine area influence walking, whereas ipsilateral thalamocortical projections influence reaching.     

Bilateral effects of unilateral subthalamic nucleus deep brain stimulation in advanced Parkinson's disease

To investigate the bilateral effects of unilateral subthalamic nucleus deep brain stimulation (STN-DBS), we prospectively studied 9 consecutive advanced Parkinson's disease (PD) patients (2 men and 7 women) who underwent unilateral STN-DBS. Patients were evaluated preoperatively and at 3 and 6 months postoperatively with and without dopaminergic medications ('on' and 'off' medication, respectively). Postoperatively, patients were assessed with and without stimulation. We found that, when compared with baseline, the 'off' medication scores of the Unified Parkinson's Disease Rating Scale motor part (UPDRS III) and activities of daily living (UPDRS II) were improved by 37% (p = 0.028) and 50% (p = 0.046) at 6 months after surgery, respectively. Stimulation while 'off' medication improved the total UPDRS score by 42% (p = 0.028) at 6 months. At 6 months after surgery, the subscore of UPDRS III of body parts contralateral to the DBS implantation had improved by 48% (p = 0.028), and the ipsilateral subscore of UPDRS III and the axial subscore of UPDRS III had improved by 20% (p = 0.027) and 39% (p = 0.028), respectively. Daily dosage of levodopa was reduced by 15% at 6 months. No patient exhibited permanent side effects. These findings indicate that unilateral STN-DBS may be a reasonable surgical procedure for selected PD patients who have markedly asymmetric parkinsonism.     

Four year follow-up study after unilateral pallidotomy in advanced Parkinson's disease

BACKGROUND: Pallidotomy is widely accepted as a treatment for patients with Parkinson's disease (PD) who have disabling symptoms that are inadequately controlled with pharmacotherapy. There are, however, only a few studies, with a small number of patients, showing evidence after prolonged periods of time about the clinical outcome after pallidotomy. METHODS: We have conducted a four-year follow-up study of 23 patients with PD who had undergone unilateral pallidotomy. Six patients were lost to follow-up. The remaining 17 were evaluated before surgery and at three months, one year, and four years after surgery, following standard protocols. RESULTS: At four years, patients still showed significant amelioration in contralateral and axial dyskinesias and off-period contralateral parkinsonian signs. Total motor UPDRS and Activities of Daily Living scores also remained improved four years after surgery. Ipsilateral and axial parkinsonian symptoms and Hoehn & Yahr and Schwab & England scales were not significantly changed from baseline values. The initial beneficial effects on motor fluctuations were not maintained at last visit. All patients considered themselves to be improved with respect to their clinical condition before surgery in a clinical global impression estimation done at the four-year follow-up. CONCLUSION: Unilateral pallidotomy can provide sustained improvement of contralateral parkinsonism and dyskinesias during at least four years. Early benefits observed in axial symptoms and motor fluctuations wane with time. On period akinesia worsened significantly in the limbs contralateral to pallidotomy after four years.     

Outcome of unilateral pallidotomy in advanced Parkinson's disease: cohort study of 32 patients

OBJECTIVES: In a randomised trial to study the efficacy of unilateral pallidotomy in patients with advanced Parkinson's disease, patients having pallidotomy within 1 month after randomisation were compared with patients having pallidotomy 6 months after the primary outcome assessment. Of the 37 patients enrolled 32 had a unilateral pallidotomy. The follow up study of these patients is presented to report (1) clinical outcome; (2) adverse effects; (3) cognitive and behavioural effects; (4) relation between lesion location and outcome; and (5) preoperative patient characteristics predictive for good outcome. METHODS: Outcome measures were the motor section of the unified Parkinson's disease rating scale (UPDRS), levodopa induced dyskinesias, disability, quality of life, and a comprehensive neuropsychological assessment. Multivariate logistic regression was used to identify preoperative patient characteristics independently associated with good outcome. RESULTS: Off phase assessment showed a reduction in parkinsonism from 49 to 36.5 points on the UPDRS 6 months after surgery. Improvements were also demonstrated for activities of daily living and quality of life. In the on phase dyskinesias were reduced. All effects lasted up to 12 months after surgery. Three patients had major permanent adverse effects. Besides worsening of verbal fluency after left sided surgery, systematic cognitive deterioration was not detected. Patients taking less than 1000 levodopa equivalent units (LEU)/day were more likely to improve. CONCLUSIONS: The positive effects of unilateral pallidotomy are stable up to 1 year after surgery. Patients taking less than 1000 LEU per day were most likely to improve.     

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.     

Efficacy and safety of simultaneous bilateral pallidotomy in advanced Parkinson's disease

BACKGROUND: Although unilateral pallidotomy is generally considered a safe and effective neurosurgical treatment for advanced Parkinson's disease (PD), controversies concerning efficacy and adverse effects of bilateral posteroventral pallidotomy (PVP) exist and need to be resolved. METHODS: We studied 8 patients with advanced PD who underwent simultaneous bilateral PVP. The patients were assessed preoperatively, immediately after surgery, and 6 and 12 months later. RESULTS: Dyskinesia was almost entirely abolished immediately after surgery, as well as being significantly lower 1 year later (p < 0.05). The 'off' medication score of the Unified Parkinson's Disease Rating Scale motor part (UPDRS III) was significantly improved after surgery (p < 0.05) but increased gradually after 6 months. The off medication score of activities of daily living tended to improve immediately after surgery, but it returned to preoperative levels at 12 months. There were no major complications of surgery. CONCLUSIONS: Simultaneous bilateral PVP may be a safe and highly effective method of reducing levodopa-induced dyskinesia. Our results suggest that simultaneous bilateral PVP may be a reasonable therapeutic option for advanced PD with severe levodopa-induced dyskinesia.     

Unilateral and bilateral pallidotomy for idiopathic Parkinson's disease: a case series of 115 patients.

Lesioning of the internal pallidum is known to improve the symptoms of idiopathic Parkinson's disease (PD) and alleviate dyskinesia and motor fluctuations related to levodopa therapy. The benefit obtained contralateral to a single lesion is insufficient in some cases when symptoms are bilaterally disabling. However, reports of unacceptably high rates of adverse effects after bilateral pallidotomy have limited its use in such cases. We report on the outcome of unilateral (UPVP) and bilateral (BPVP) posteroventral pallidotomy in a consecutive case series of 115 patients with PD in the United Kingdom and Australia. After 3 months, UPVP resulted in a 27% reduction in the off medication Part III (motor) Unified Parkinson's Disease Rating Scale score and abolition of dyskinesia in 40% of cases. For BPVP, these figures were increased to 31% and 63%, respectively. Follow-up of a smaller group to 12 months found the motor scores to be worsening but benefit to dyskinesia and activities of daily living was maintained. Speech was adversely affected after BPVP, although the change was small in most cases. Unilateral and bilateral pallidotomy can be performed safely without microelectrode localisation. Bilateral pallidotomy appears to be more effective, particularly in reducing dyskinesia; in our experience, the side effects have not been as high as reported by other groups.     

GPi pallidotomy for Parkinson's disease with drug-induced psychosis

Levodopa-induced psychosis may seriously threaten the ability of patients with Parkinson's disease (PD) to continue leading an independent life. A retrospective assessment of the therapeutic effects of the globus pallidus internus (GPi) pallidotomy on the activities of daily living (ADL) of seven PD patients presenting with mild or moderate degrees of psychosis was carried out. Their scores according to the Unified Parkinson's Disease Rating Scale (UPDRS) Part I-2 (maximum=4) were 2 or 3 (mean +/- SD=2.4 +/- 0.5). Bilateral procedure was needed in 5 out of 7 patients to obtain sufficient improvement of motor symptoms. At 3 months after surgery, UPDRS part III motor scores in the 'off' state were significantly decreased and motor fluctuations were abolished. Nevertheless, their score of Schwab and England (S-E) ADL scale scores responded poorly to the surgery, while the scores in other 12 patients without psychosis was significantly improved after pallidotomy. The data indicate that GPi pallidotomy ameliorates the motor symptoms in patients with drug-induced psychosis (DIP), but has no significant impact on their consequent daily activities. A regression model for all 19 patients who underwent pallidotomy revealed that postoperative S-E scale was affected by the preoperative UPDRS Part I-2 rather than by Part III motor score. The present study suggested that DIP, even if its degree is not severe, may be a limiting factor of the therapeutic potential of pallidotomy in patients with PD.     

Unilateral pallidotomy for Parkinson''s disease: results after more than 1 year

OBJECTIVE: To examine follow up results of unilateral ventral medial pallidotomy in 22 patients with advanced Parkinson's disease more than 1 year after the operation in comparison with their results (previously reported) at 3 months. METHODS: Twenty patients who had undergone unilateral pallidotomy were assessed with the core assessment programme for intracerebral transplantation (CAPIT) protocol preoperatively, at 3 months postoperatively, and again after a median postoperative follow up of 14 months. Two further patients had only one evaluation 3 months postoperatively. RESULTS: The reduction of contralateral dyskinesias (median 67%) at 3 months was slightly attenuated after 1 year to 55% (both p<0.001 compared with baseline). A less pronounced effect on ipsilateral and axial dyskinesias decreased from 39% to 33% (p<0.005 and p<0.01), and from 50% to 12.5% (p<0.001 and p<0.01), respectively. However, there was no significant change between the 3 month and the follow up assessment. The modest improvement of the contralateral unified Parkinson's disease rating scale (UPDRS) motor score in the "off" state remained improved compared with preoperative levels, but less significantly (26%, p<0.001, and 18%, p<0.01). The activities of daily living (ADL) subscore of the UPDRS in the off state remained improved with median changes of 23% and 22% at follow up (both p<0. 005). There was no significant improvement of "on" state or ipsilateral off state motor scores. Median modified Hoehn and Yahr scores in off and on state were unchanged, as was the time spent off. Speech in off had significantly deteriorated by 1 year after the operation. CONCLUSIONS: The beneficial effects of unilateral pallidotomy persist for at least 12 months and, dyskinesias are most responsive to this procedure.     

Subthalamic deep brain stimulation in patients with a previous pallidotomy.

The safety and efficacy of subthalamic nucleus (STN) deep brain stimulation (DBS) in patients who have had a previous unilateral pallidotomy is not clear. We identified 10 patients (9 male) at the Baylor College of Medicine Parkinson's Disease Center who underwent STN DBS after prior unilateral pallidotomy. Demographics, efficacy as determined by off Unified Parkinson's Disease Rating Scale (UPDRS) part III scores, and levodopa equivalent dosing were analyzed. We then compared these to an age- and sex-matched group of 25 DBS patients who had no prior pallidotomy. After their initial pallidotomy (mean age, 51.8 +/- 10.8 years), the mean UPDRS motor off medicine scores improved from 51.3 +/- 14.3 to 34.9 +/- 12.8, and the UPDRS dyskinesia score improved from 1.8 +/- 1.0 to 0.8 +/- 0.7. Their STN DBS off UPDRS motor scores (mean age, 56.0 +/- 10.2 years) improved by 16.0% from 53.1 +/- 9.7 (range, 42-68) to 44.6 +/- 11.1 (range, 25-67). In contrast, the UPDRS off motor scores in a control group of 25 DBS patients improved by 49.9%, from 49.7 +/- 11.1 to 25.7 +/- 18.9, (16.0% vs. 49.9%; P < 0.001). Changes in UPDRS dyskinesia scores were similar in both groups. AE thought to be related to the STN DBS following pallidotomy included worse dysarthria (three) and worse balance (two). STN DBS patients with prior pallidotomy had less improvement in UPDRS off motor score compared to other STN DBS patients, despite relatively good outcomes immediately after their pallidotomy. This may be partially due to a selection bias, but it may also indicate that prior pallidotomy is a negative predictor of outcome of STN DBS and should be considered in patient selection.     

Stimulation of the subthalamic nucleus in Parkinson's disease: a 5 year follow up

BACKGROUND: The short term benefits of bilateral stimulation of the subthalamic nucleus (STN) in patients with advanced levodopa responsive Parkinson's disease (PD) are well documented, but long term benefits are still uncertain. OBJECTIVES: This study provides a 5 year follow up of PD patients treated with stimulation of the STN. METHODS: Thirty seven consecutive patients with PD treated with bilateral STN stimulation were assessed prospectively 6, 24, and 60 months after neurosurgery. Parkinsonian motor disability was evaluated with and without levodopa treatment, with and without bilateral STN stimulation. Neuropsychological and mood assessments included the Mattis Dementia Rating Scale, the frontal score, and the Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: No severe peri- or immediate postoperative side effects were observed. Six patients died and one was lost to follow up. Five years after neurosurgery: (i) activity of daily living (Unified Parkinson Disease Rating Scale (UPDRS) II) was improved by stimulation of the STN by 40% ("off" drug) and 60% ("on" drug); (ii) parkinsonian motor disability (UPDRS III) was improved by 54% ("off" drug) and 73% ("on" drug); (iii) the severity of levodopa related motor complications was decreased by 67% and the levodopa daily doses were reduced by 58%. The MADRS was unchanged, but cognitive performance declined significantly. Persisting adverse effects included eyelid opening apraxia, weight gain, addiction to levodopa treatment, hypomania and disinhibition, depression, dysarthria, dyskinesias, and apathy. CONCLUSIONS: Despite moderate motor and cognitive decline, probably due to disease progression, the marked improvement in motor function observed postoperatively was sustained 5 years after neurosurgery.     

Treatment of advanced Parkinson's disease by unilateral posterior GPi pallidotomy: 4-year results of a pilot study.

To assess the long-term outcome following unilateral pallidotomy for advanced Parkinson's disease, we performed nonblinded Core Assessment Program for Intracerebral Transplantations protocol assessments in 10 of the original 15 patients in our pilot study for 4 years following surgery. Although Unified Parkinson's Disease Rating Scale motor examination scores returned to baseline levels at 3 and 4 years, most patients continued to show sustained improvements in contralateral tremor, akinesia, and drug-induced dyskinesias. Contralateral tremor was absent at 4 years in all seven patients with preoperative tremor. Contralateral "off" arm movement times (averaged for three tasks) decreased by 37% at 1 year and by 30% at 4 years. Contralateral dyskinesia scores improved by 82% at 1 year and by 64% at 4 years. In contrast, after reaching speeds equal to the contralateral side at 1 year, ipsilateral "off" movement times increased by 13% over baseline levels at 4 years. Although most gait and postural stability measures showed modest initial improvement followed by a return to baseline values, "on" stand-walk-sit task performance declined significantly at 4 years. Despite the restriction of our surgeries to one side and the expected natural progression of Parkinson's disease, the results of patient self-assessments suggest that 4 years after unilateral pallidotomy, most patients continue to experience a quality of life above preoperative levels.     

Intravenous amantadine improves levadopa-induced dyskinesias: an acute double-blind placebo-controlled study.

Experimental evidence suggests that glutamatergic receptor blockade may improve the motor response complications associated with long-term levodopa treatment in Parkinson's disease (PD) patients. Our objective was to evaluate the acute effect of amantadine, a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor, on levodopa-induced dyskinesias, and to gain further insights into the antidyskinetic mechanism of this drug. Nine PD patients with motor fluctuations and severely disabling peak of dose dyskinesias received their first morning levodopa dose, followed by a 2-hour intravenous amantadine (200 mg) or placebo infusion, on two different days. Parkinsonian symptoms and dyskinesias were assessed every 15 minutes during the infusion and for 3 hours thereafter, while patients were taking their usual oral antiparkinsonian therapy, by means of Unified Parkinson's Disease Rating Scale (UPDRS, motor examination), tapping test, and a modified Abnormal Involuntary Movement Scale (AIMS). Intravenous amantadine acutely improved levodopa-induced dyskinesias by 50%without any loss of the anti-parkinsonian benefit from levodopa. This study confirms the antidyskinetic effect of amantadine and strengthens the rationale for using antiglutamatergic drugs in the treatment of parkinsonian motor fluctuations.     

Stereotactic posteroventral pallidotomy: clinical methods and results at 1-year follow up.

Twenty consecutive patients with idiopathic Parkinson's disease underwent stereotactic posteroventral pallidotomy. Schwab and England ADL scores in the "off" state were improved by 18% and in the "on" state the scores declined by 2%. Three patients also reported marked improvement in "off" state dystonia. One-year data are available on 12 patients who underwent evaluations according to the Core Assessment Program for Intracerebral Transplantation protocol preoperatively and at 3, 6, and 12 months after surgery. Significant improvements in Unified Parkinson's Disease Rating Scale sections II and III scores in the "off" state, composite "off" state scores of bradykinesia and rigidity, contralateral tremor in the "off" state, and contralateral dyskinesias were observed. Although there was reduction in the daily levodopa dose, this did not reach statistical significance. Major complications (15%) included hemiparesis (one of 20) and visual field cuts (two of 20); minor complications (45%) included mild cognitive dysfunction (four of 20), reading difficulty not related to visual disturbance (one of 20), and 5-10 lb weight gain (four of 20).     

Amantadine reduces the duration of levodopa-induced dyskinesia: a randomized, double-blind, placebo-controlled study

We evaluated the effects of amantadine on levodopa-induced dyskinesia (LID) in eighteen consecutive Parkinson's disease (PD) patients in a randomized, double-blind, placebo-controlled study. The primary outcomes were the Clinical Dyskinesia Rating Scale (CDRS) and the Unified Parkinson's Disease Rating Scale (UPDRS) part IVa score changes. The secondary outcomes were the UPDRS II and III score changes. Amantadine did not change the CDRS score for hyperkinesia or dystonia, but decreased the duration of LID and its influence on daily activities (p=0.04) and the UPDRS II score (p=0.01) more than placebo. These findings show that amantadine reduces the duration of LID and improves motor disability in PD.     

Unilateral thalamotomy for the treatment of tremor dominant Parkinson's disease

BACKGROUND AND PURPOSE: To assess the effectiveness of unilateral thalamotomy for the treatment of parkinsonian tremor and other motor signs of Parkinson's disease (PD). MATERIAL AND METHODS: Between 1999 and 2004, 41 patients with idiopathic tremor dominant PD were treated surgically in the Neurosurgical Department of Postgraduate Medical Center in Warsaw. Stereotactic thalamotomy was performed with Leksell stereotactic frame (model G) using intraoperative macrostimulation. The patients were assessed according to the Unified Parkinson's Disease Rating Scale version 3. (UPDRS) before and after thalamotomy in the off state. The progression of PD was also evaluated according to the Hoehn and Yahr scale in the off state and also Schwab and England was used to assess the disability of the patients. The patients were evaluated before thalamotomy in the off state, and 3, 12, 24 and 36 months after surgery, according to the above mentioned clinical rating scales. RESULTS: The authors report their results among 41 patients who underwent stereotactic thalamotomy 3 years postoperatively. At 3 years follow-up (in the group of 19 patients) the contralateral tremor from the presurgical value of 11.2 (items 20 - 21 UPDRS) decreased to 2.6. The rigidity in contralateral limbs at 3 years follow-up was 1.7 (item 22 UPDRS) when compared to 2.8 (item 22 UPDRS) preoperative value. Thalamotomy had no effect on bradykinesia or other manifestations of PD such as balance or gait disturbance. There were 13 transient and 6 permanent complications. CONCLUSIONS: Thalamotomy using intraoperative macrostimulation in carefully selected patients is a beneficial operation for the control of medically refractory parkinsonian resting and postural tremor. The effect of unilateral thalamotomy on tremor is long lasting.     

Long term outcome of unilateral pallidotomy: follow up of 15 patients for 3 years

OBJECTIVES: With the advent of new antiparkinsonian drug therapy and promising results from subthalamic and pallidal stimulation, this study evaluated the long term efficacy of unilateral pallidotomy, a technique which has gained popularity over the past decade for the management of advanced Parkinson's disease. METHODS: The 15 patients reported here are part of the original cohort of 24 patients who underwent posteroventral pallidotomy for motor fluctuations and disabling dyskinesias 3 years ago as part of a prospective study. Evaluation scales included the unified Parkinson's disease rating scale, the Goetz dyskinesia scale, and the Purdue pegboard test. RESULTS: When compared with the prepallidotomy scores, the reduction in the limb dyskinesias and off state tremor scores persisted on the side contralateral to pallidotomy at the end of 3 years (dyskinesias were reduced by 64% (p<0.01) and tremor by 63% (p<0.05). Other measures tended to deteriorate. The dosage of antiparkinsonian medications did not change significantly from 3 months prepallidotomy to 3 years postpallidotomy. CONCLUSIONS: Although unilateral pallidotomy is useful in controlling the contralateral dyskinesias and tremor 3 years after surgery, all other early benefits disappear and activities of daily living continue to worsen.