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Biomedical subjects

P R Schuurman

Publications and source records attributed to P R Schuurman.

At least 19 recordsLinked to original sources
PubMed2007

Pathological gambling after bilateral subthalamic nucleus stimulation in Parkinson disease.

We describe a patient with advanced Parkinson's disease who developed pathological gambling within a month after successful bilateral subthalamic nucleus (STN) stimulation. There was no history of gambling. On neuropsychological testing, slight cognitive decline was evident 1 year after surgery. Stimulation of the most dorsal contact with and without medication induced worse performances on decision making tests compared with the more ventral contact. Pathological gambling disappeared after discontinuation of pergolide and changing the stimulation parameters. Pathological gambling does not seem to be associated with decision making but appears to be related to a combination of bilateral STN stimulation and treatment with dopamine agonists.

Antiparkinson Agents↗
PubMed2006

Unilateral pallidotomy versus bilateral subthalamic nucleus stimulation in Parkinson's disease: one year follow-up of a randomised observer-blind multi centre trial.

BACKGROUND: To investigate whether STN stimulation is more efficacious than unilateral pallidotomy in advanced Parkinson's disease (PD) one year after surgery. METHOD: Thirty-four patients with advanced PD were randomly assigned to unilateral pallidotomy or bilateral STN stimulation. Outcome measures were parkinsonian symptoms in off and on phases (UPDRS 3), dyskinesias, functional status, Parkinson's disease quality of life questionnaire, the effects on separate symptoms, timed tests, patient diaries, dopaminergic drugs changes, adverse effects, and global outcome scale. Patients were assessed before surgery, six months and one year after surgery. The primary outcome measure was the off phase UPDRS 3 at six months follow-up. FINDINGS: The off phase UPDRS 3 score improved from 46.5 to 32 points in the pallidotomy patients and from 51.5 to 24 in the STN stimulation patients (p = 0.002). On phase UPDRS 3 and off phase Schwab and England functional scale improved significantly in favour of the STN stimulation patients. Dopaminergic drugs reduction was larger in the STN group although the difference between the treatment groups was not significant. One patient in each group had a major adverse effect. CONCLUSIONS: Bilateral STN stimulation is more efficacious than unilateral pallidotomy in advanced PD up to one year after surgery.

Activities of Daily Living↗
PubMed2006

Neuropsychological effects of bilateral STN stimulation in Parkinson disease: a controlled study.

OBJECTIVE: To evaluate the cognitive and behavioral effects of bilateral subthalamic nucleus (STN) stimulation in patients with Parkinson disease (PD). METHODS: The authors included 103 patients; 99 patients were evaluated 6 months after surgery. A control group of 39 patients with PD was formed and 36 patients were evaluated 6 months later. At baseline and at follow-up we administered neuropsychological tests of language, memory, visuospatial function, mental speed, and executive functions. A depression rating scale, a quality of life scale, self and proxy ratings of memory and dysexecutive symptoms, and a neuropsychiatric interview were also administered. RESULTS: Six months after surgery, the STN group showed a larger decline than the control group on measures of verbal fluency, color naming, selective attention, and verbal memory. Moreover, the STN group showed a decrease in positive affect, and an increase in emotional lability and cognitive complaints. On the other hand, the STN group showed an increase in quality of life and a slight decrease in depressive symptoms. Nine percent of the STN patients had psychiatric complications (vs 3% of controls). CONCLUSIONS: Bilateral subthalamic nucleus stimulation has an adverse effect on executive functions with implications for daily life of the patients and their relatives.

Cognition Disorders↗
PubMed2004

Unilateral pallidotomy versus bilateral subthalamic nucleus stimulation in PD: a randomized trial.

OBJECTIVE: To compare the efficacy of unilateral pallidotomy and bilateral subthalamic nucleus (STN) stimulation in patients with advanced Parkinson disease (PD) in a randomized, observer-blind, multicenter trial. METHODS: Thirty-four patients with advanced PD were randomly assigned to have unilateral pallidotomy or bilateral STN stimulation. The primary outcome was the change from baseline to 6 months in the motor part of the Unified PD Rating Scale (motor UPDRS) in the off phase. Secondary outcomes were parkinsonian symptoms in the on phase (motor UPDRS), dyskinesias (Clinical Dyskinesia Rating Scale and dyskinesias UPDRS), functional status (activities of daily living UPDRS and Schwab and England scale), PD Quality of Life questionnaire, changes in drug treatment, and adverse effects. RESULTS: The off phase motor UPDRS score improved from 46.5 to 37 points in the group of pallidotomy patients and from 51.5 to 26.5 in the STN stimulation patients (p = 0.002). Of the secondary outcome measures, on phase motor UPDRS and dyskinesias UPDRS improved significantly in favor of the STN stimulation patients. Reduction of antiparkinsonian drugs was greater after STN stimulation than after pallidotomy. One patient in each group had a major adverse effect. CONCLUSIONS: Bilateral STN stimulation is more effective than unilateral pallidotomy in reducing parkinsonian symptoms in patients with advanced PD.

Aged↗
PubMed2002

A comparison of neuropsychological effects of thalamotomy and thalamic stimulation.

OBJECTIVE: The neuropsychological effects of thalamotomy and thalamic stimulation in patients with severe drug-resistant tremor due to PD, essential tremor (ET), or MS were compared in a randomized trial. METHODS: Complete neuropsychological evaluations at baseline and 6 months after surgery were obtained in 62 patients who underwent thalamotomy (n = 32: 21 PD, 6 ET, 5 MS) or thalamic stimulation (n = 30: 19 PD, 7 ET, 4 MS). RESULTS: Six months after thalamotomy, a decline was seen in the scores of the Stroop Color-Word Test, with the exception of the interference score. In the thalamic stimulation group, no significant changes were found on any of the cognitive tests. Age, diagnosis, disease severity, and baseline cognitive status were not correlated to cognitive changes. A difference in score changes between right- and left-sided surgery was found in verbal fluency and Stroop Test scores after both thalamotomy and thalamic stimulation. CONCLUSIONS: Both thalamotomy and thalamic stimulation are associated with a minimal overall risk of cognitive deterioration. Verbal fluency decreased after both left-sided thalamotomy and thalamic stimulation.

Adult↗
PubMed2002

Morbidity and mortality following pallidotomy in Parkinson's disease: a systematic review.

OBJECTIVE: To study the frequency of morbidity and mortality associated with pallidotomy. METHOD: The authors searched the MEDLINE electronic database for pallidotomy articles reported between January 1992 and December 2000. They selected studies by the following criteria: original clinical data, unequivocal description of morbidity and mortality, and unselected consecutive cases. The authors extracted the following data: number of patients, unilateral or bilateral procedures, age, localization technique, follow-up time, number of patients with adverse effects, number of patients with permanent adverse effects (>3 months), types of adverse effects, and mortality. RESULTS: For unilateral pallidotomy, 12 prospective studies included 334 patients. Of these patients, 30.2% (95% CI, 25.3 to 35.2) had adverse effects, and 13.8% (95% CI, 10.1 to 17.5) had permanent adverse effects. A symptomatic infarction or hemorrhage occurred in 3.9% (95% CI, 2.1 to 6.6). The mortality rate was 1.2% (95% CI, 0.3 to 3.0). In the series with microelectrode recording, the frequency of adverse effects was 14.4% (95% CI, 4.7 to 24.1) higher and the frequency of stroke was 4.9% (95% CI, 1.4 to 8.4) higher. The most frequent adverse effects were problems with speech (11.1%) and facial paresis (8.4%). For bilateral pallidotomy, five historical cohort studies including 20 patients were available for review. Fourteen patients had an adverse effect, and the most frequent adverse effects were impairments of speech and cognition. CONCLUSIONS: The risk of permanent adverse effects associated with unilateral pallidotomy was 13.8%. A symptomatic infarction or hemorrhage occurred in 3.9% of patients, and the associated mortality rate was 1.2%.

Humans↗
PubMed2001

[Stereotaxic neurosurgery for treatment of Parkinson disease].

Three target structures are available in stereotactic surgery for Parkinson's disease: the thalamus, the globus pallidus and the subthalamic nucleus. The subthalamic nucleus appears to be the most promising structure. However, the thalamus can be considered in the case of an incapacitating tremor presenting as a primary symptom. Surgery in the globus pallidus may be as effective as in the subthalamic nucleus, but in the latter it is often accompanied by a reduction in dopaminergic medication. The surgical technique of electrical stimulation causes fewer adverse effects than that of coagulation and can therefore be applied bilaterally, but does require more intense postoperative care. In the selection of patients for surgery, levodopa responsiveness plays an important role in predicting effectiveness, except in the case of tremor.

Electric Stimulation Therapy↗
PubMed2001

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.

Activities of Daily Living↗
PubMed2000

A comparison of continuous thalamic stimulation and thalamotomy for suppression of severe tremor.

BACKGROUND: Deep-brain stimulation through an electrode implanted in the thalamus was developed as an alternative to thalamotomy for the treatment of drug-resistant tremor. Stimulation is thought to be as effective as thalamotomy but to have fewer complications. We examined the effects of these two procedures on the functional abilities of patients with drug-resistant tremor due to Parkinson's disease, essential tremor, or multiple sclerosis. METHODS: Sixty-eight patients (45 with Parkinson's disease, 13 with essential tremor, and 10 with multiple sclerosis) were randomly assigned to undergo thalamotomy or thalamic stimulation. The primary outcome measure was the change in functional abilities six months after surgery, as measured by the Frenchay Activities Index. Scores for this index can range from 0 to 60, with higher scores indicating better function. Secondary outcome measures were the severity of tremor, the number of adverse effects, and patients' assessment of the outcome. RESULTS: Functional status improved more in the thalamic-stimulation group than in the thalamotomy group, as indicated by increases in the score for the Frenchay Activities Index (from 31.4 to 36.3 and from 32.0 to 32.5, respectively; difference between groups, 4.4 points; 95 percent confidence interval, 2.0 to 6.9). After adjustment for base-line characteristics, multivariate analysis also showed that the thalamic-stimulation group had greater improvement (difference between groups, 5.1 points; 95 percent confidence interval, 2.3 to 7.9). Tremor was suppressed completely or almost completely in 27 of 34 patients in the thalamotomy group and in 30 of 33 patients in the thalamic-stimulation group. One patient in the thalamic-stimulation group died perioperatively after an intracerebral hemorrhage. With the exception of this incident, thalamic stimulation was associated with significantly fewer adverse effects than thalamotomy. Functional status was reported as improved by 8 patients in the thalamotomy group, as compared with 18 patients in the thalamic-stimulation group (P=0.01). CONCLUSIONS: Thalamic stimulation and thalamotomy are equally effective for the suppression of drug-resistant tremor, but thalamic stimulation has fewer adverse effects and results in a greater improvement in function.

Activities of Daily Living↗
PubMed1999

Unilateral pallidotomy in Parkinson's disease: a randomised, single-blind, multicentre trial.

BACKGROUND: The results of several cohort studies suggest that patients with advanced Parkinson's disease would benefit from unilateral pallidotomy. We have assessed the efficacy of unilateral pallidotomy in a randomised, single-blind, multicentre trial. METHODS: We enrolled 37 patients with advanced Parkinson's disease who had, despite optimum pharmacological treatment, at least one of the following symptoms: severe response fluctuations, dyskinesias, painful dystonias, or bradykinesia. Patients were randomly assigned to unilateral pallidotomy within 1 month or to pallidotomy after the primary outcome assessment (6 months later). The primary outcome was the difference between the groups in median changes on the motor examination section of the unified Parkinson's disease rating scale (UPDRS 3) score done in the off phase. Secondary outcome measures included levodopa-induced dyskinesias (dyskinesia rating scale [DRS]) and extent of disability (UPDRS 2). FINDINGS: The median UPDRS 3 off score of the pallidotomy patients improved from 47 to 32.5, whereas that of control patients slightly worsened from 52.5 to 56.5 (p<0.001). In the on phase the median DRS score improved 50% in pallidotomy patients compared with no change in controls. The UPDRS 2 off score improved with a median of 7 in the pallidotomy group. Two treated patients had major adverse effects. INTERPRETATION: Unilateral pallidotomy is an effective treatment in patients with advanced Parkinson's disease, who have an unsatisfactory response to pharmacological treatment.

Aged↗
PubMed1999

Unilateral pallidotomy in advanced Parkinson's disease: a retrospective study of 26 patients.

OBJECTIVE: To evaluate the effects of unilateral pallidotomy in patients with Parkinson's disease (PD). PATIENTS AND METHODS: Twenty-six patients with PD and disabling dyskinesias, painful and/or disabling dystonia, and/or pain as part of PD despite optimal pharmacotherapy underwent unilateral pallidotomy. For assessment, the Unified Parkinson's Disease Rating Scale (UPDRS; part II and III), Hoehn and Yahr staging, the Schwab and England scale, a Dyskinesia Rating Scale, and timed tests were used. Assessment was performed in defined "off' and "on," and on average 2 months before and 7.5 months after the unilateral pallidotomy. Adverse effects were classified as transient or permanent and as major or minor. RESULTS: In the "off' phase, the median UPDRS II score improved from 26.5 to 20.5 (23%) and the median UPDRS III score improved from 47.5 to 33.0 (31%). In the "on" phase, dyskinesias contralateral to the side of the procedure improved with 88% ipsilateral dyskinesias improved only temporarily, and the total UPDRS II and III scores remained unchanged. Thirteen patients had transient adverse effects, three patients had permanent, and two patients had a combination of transient and permanent adverse effects. The transient adverse effects in two patients were classified as major. CONCLUSION: Stereotactic unilateral pallidotomy can improve symptoms and disability in the "off' phase. In the "on" phase, dyskinesias disappeared at the side contralateral to the procedure. Permanent minor complications of pallidotomy occurred in 19% of the patients.

Adult↗
PubMed1999

Intraoperative changes of transcranial Doppler velocity: relation to arterial oxygen content and whole-blood viscosity.

The association of arterial oxygen content (CaO2) and viscosity with transcranial Doppler (TCD) blood flow velocity in the middle cerebral artery was studied in 20 adults without cerebrovascular disease undergoing abdominal surgery associated with significant fluctuations in hematology. TCD measurements and arterial blood samples were obtained before and directly after surgery but before blood transfusion. There was an inverse association between baseline mean velocity and CaO2 (r = -0.56), hematocrit (r = -0.50), hemoglobin (r = -0.51), and high-shear viscosity (r = -0.46). After intraoperative blood loss, intraindividual fluctuations of TCD measurements, blood oxygenation, and rheologic factors were studied. In multiple regression analysis, changes in CaO2 had the strongest association with changes in TCD values, accounting for 55% of the variation in mean velocity. Addition of hematocrit and viscosity could not account for more variation in mean velocity than CaO2 alone.

Abdomen↗
PubMed1999

A prospective comparison between three-dimensional magnetic resonance imaging and ventriculography for target-coordinate determination in frame-based functional stereotactic neurosurgery.

OBJECT: The purpose of this prospective study was to compare stereotactic coordinates obtained with ventriculography with coordinates derived from stereotactic computer-reconstructed three-dimensional magnetic resonance (3D-MR) imaging in functional stereotactic procedures. METHODS: In 15 consecutive patients undergoing functional stereotactic procedures, both preoperative frame-based stereotactic 3D-MR imaging and intraoperative ventriculography were performed. Differences between 3D-MR imaging and ventriculography in X, Y, and Z coordinates of the anterior commissure (AC), posterior commissure (PC), and target area were calculated, as well as the 3D distance between the position of AC, PC, and target within stereotactic space as obtained using both methods. The position of the stereotactic MR imaging fiducial markers measured using 3D-MR imaging compared well with the markers' known position embedded in the software (mean error 0.4 mm, maximal error for an individual slice 1.2 mm). For the individual coordinates, only for Y-PC was a difference found between 3D-MR imaging and ventriculography that significantly exceeded half the size of a pixel, the theoretical limit of precision when using a digitized imaging technique. However, the mean difference was smaller than 1 mm. The mean 3D distance between the 3D-MR imaging- and ventriculography-derived coordinates was 1.09 mm for AC, 1.13 mm for PC, and 1.29 mm for the targets. CONCLUSIONS: With these data it is shown that there is sufficient agreement between ventriculography-derived and 3D-MR imaging-derived stereotactic coordinates to justify the use of 3D-MR imaging target determination in frame-based functional stereotactic neurosurgery.

Brain Mapping↗
PubMed1998

[Neurosurgical stereotactic treatment in Parkinson's disease].

For patients with Parkinson's disease who have become unresponsive to pharmacotherapy or have developed severe motor complications due to medical therapy, a number of symptomatic neurosurgical interventions are available: thalamotomy, thalamic stimulation and pallidotomy. These stereotactic operations are performed under local anaesthesia. The target is located using anatomical and physiological techniques, after which the neuro-ablative or neuromodulatory procedure is performed. The choice of the target depends on the symptoms of the patient that most impair daily functioning. In case of dominating tremor, thalamic surgery is performed. Patients who are mainly incapacitated by rigidity, hypokinesia or pharmacotherapy-induced dyskinesias are suitable candidates for pallidotomy. Contraindications are cognitive dysfunction, severe disturbance of gait and balance, advanced cerebral atrophy on CT or MRI, limited life expectancy and a poor general condition enhancing surgical risk, e.g. coagulation disorders or uncontrolled hypertension. Surgical treatment of Parkinson's disease is being carried out in clinical trials in the Netherlands in the Academic Medical Centre in Amsterdam, the Academic Hospital in Groningen and the St. Elisabeth Hospital in Tilburg.

Contraindications↗
PubMed1998

Thalamic surgery and tremor.

The results of thalamotomy for the various kinds of tremor are described. The nomenclature of the ventrolateral thalamic nuclei is discussed. Long-term thalamic stimulation seems a promising addition to or alternative for the thalamotomy, but this has still to be proven by a prospective trial that includes a cost-effectiveness analysis.

Electric Stimulation↗