Mathieu W.P.M. Lenders

Subthalamic nucleus versus globus pallidus bilateral deep brain stimulation for advanced Parkinson's disease (NSTAPS study): a randomised controlled trial

BACKGROUNDnPatients with advanced Parkinsons disease often have rapid swings between mobility and immobility, and many respond unsatisfactorily to adjustments in pharmacological treatment. We assessed whether globus pallidus pars interna (GPi) deep brain stimulation (DBS) gives greater functional improvement than does subthalamic nucleus (STN) DBS.nnnMETHODSnWe recruited patients from five centres in the Netherlands who were aged 18 years or older, had idiopathic Parkinsons disease, and had, despite optimum pharmacological treatment, at least one of the following symptoms: severe response fluctuations, dyskinesias, painful dystonias, or bradykinesia. By use of a computer-generated randomisation sequence, we randomly assigned patients to receive either GPi DBS or STN DBS (1:1), applying a minimisation procedure according to drug use (levodopa equivalent dose <1000 mg vs ≥1000 mg) and treatment centre. Patients and study assessors (but not those who assessed adverse events) were masked to treatment allocation. We had two primary outcomes: functional health as measured by the weighted Academic Medical Center Linear Disability Scale (ALDS; weighted by time spent in the off phase and on phase) and a composite score for cognitive, mood, and behavioural effects up to 1 year after surgery. Secondary outcomes were symptom scales, activities of daily living scales, a quality-of-life questionnaire, the occurrence of adverse events, and drug use. We used the intention-to-treat principle for all analyses. This trial is registered with www.controlled-trials.com, number ISRCTN85542074.nnnFINDINGSnBetween Feb 1, 2007, and March 29, 2011, we enrolled 128 patients, assigning 65 to GPi DBS and 63 to STN DBS. We found no statistically significant difference in either of our primary outcomes: mean change in weighted ALDS (3·0 [SD 14·5] in the GPi group vs 7·7 [23·2] in the STN group; p=0·28) and the number of patients with cognitive, mood, and behavioural side-effects (36 [58%] of 62 patients in the GPi group vs 35 [56%] of 63 patients in the STN group; p=0·94). Secondary outcomes showed larger improvements in off-drug phase in the STN group compared with the GPi group in the mean change in unified Parkinsons disease rating scale motor examination scores (20·3 [16·3] vs 11·4 [16·1]; p=0·03), the mean change in ALDS scores (20·3 [27·1] vs 11·8 [18·9]; p=0·04), and medication (mean levodopa equivalent drug reduction: 546 [SD 561] vs 208 [521]; p=0·01). We recorded no difference in the occurrence of adverse events between the two groups. Other secondary endpoints showed no difference between the groups.nnnINTERPRETATIONnAlthough there was no difference in our primary outcomes, our findings suggest that STN could be the preferred target for DBS in patients with advanced Parkinsons disease.nnnFUNDINGnStichting Internationaal Parkinson Fonds, Prinses Beatrix Fonds, and Parkinson Vereniging.

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.

A Quick and Universal Method for Stereotactic Visualization of the Subthalamic Nucleus before and after Implantation of Deep Brain Stimulation Electrodes

For deep brain stimulation (DBS) of the subthalamic nucleus (STN), it would be an advantage if the STN could be visualized with fast acquisition of MR images, allowing direct and individual targeting. We present a protocol for T2-weighted, nonvolumetric fast-acquisition MRI, implemented at 8 centers in 6 countries. Acquisition time varied between 3 min 5 s and 7 min 48 s according to the center, and imaging often provided visualization of the STN on axial and coronal scans. Postoperatively, the same imaging protocol permitted visualization of the target area and DBS electrodes with minimum artifacts. This imaging technique may contribute to a decrease in the number of electrode passes at surgery.

Burst Spinal Cord Stimulation Evaluated in Patients With Failed Back Surgery Syndrome and Painful Diabetic Neuropathy

Spinal cord stimulation (SCS) is used for treating intractable neuropathic pain. Generally, it induces paresthesia in the area covered by SCS. Burst SCS was introduced as a new stimulation paradigm with good pain relief without causing paresthesia. Good results have been obtained in patients who were naive to SCS. In this study we assess the effectiveness of burst stimulation in three groups of chronic pain patients who are already familiar with SCS and the accompanying paresthesia.

A 2-center comparative study on tonic versus burst spinal cord stimulation: Amount of responders and amount of pain suppression

Introduction:Spinal cord stimulation is a safe and effective procedure applied for medically intractable neuropathic pain and failed back surgery syndrome. Recently, a novel stimulation paradigm was developed, called burst stimulation consisting of intermittent packets of closely spaced high-frequency stimuli. The design consists of 40 Hz burst mode with 5 spikes at 500 Hz per burst, with a pulse width of 1 ms and 1 ms interspike interval delivered in constant current mode. Methods and Materials:A retrospective analysis is performed looking at 102 patients from 2 neuromodulation centers, 1 in Belgium and 1 in the Netherlands. This consisted of 2 groups, 1 group who had become failures to tonic (conventional) stimulation and 1 group who still responded to tonic stimulation. All patients were switched from tonic to burst stimulation and the amount of responders as well as the amount of pain suppression was assessed. Results:Overall burst stimulation was significantly better than tonic stimulation and baseline. On average the pain on numeric rating scale (NRS) improved from 7.8 at baseline to 4.9 with tonic to 3.2 with burst stimulation. For the Belgian and Dutch centers combined, 62.5% of nonresponders to tonic stimulation did respond to burst stimulation, on average, with 43% pain suppression. Most responders to tonic further improved with burst stimulation; on average, pain suppression improved from 50.6% to 73.6.3%. The results (from both centers) did not differ for the amount of obtained pain suppression, only for the amount of responders, which could be related to the different profile of the 2 participating centers. Conclusions:Burst seems to be significantly better than tonic stimulation. It can rescue an important amount of nonresponders to tonic stimulation and can further improve pain suppression in responders to tonic stimulation.

Spinal cord stimulation in patients with painful diabetic neuropathy: A multicentre randomized clinical trial

&NA; Spinal cord stimulation causes a highly significant pain reduction and improvement of quality of life in patients with otherwise refractory diabetic neuropathic pain. &NA; Painful diabetic neuropathy (PDN) is a peripheral neuropathic pain condition that is often difficult to relieve. Spinal cord stimulation (SCS) is a proven effective therapy for various types of mixed neuropathic conditions, yet effectiveness of SCS treatment for PDN is not well established. To our knowledge, ours is the first multicentre randomized controlled trial investigating the effectiveness of SCS in patients with PDN. Sixty patients with PDN in the lower extremities refractory to conventional medical therapy were enrolled and followed for 6 months. They were randomized 2:1 to best conventional medical practice with (SCS group) or without (control group) additional SCS therapy, and both groups were assessed at regular intervals. At each follow‐up visit, the EuroQoL 5D, the short form McGill Pain Questionnaire (SF‐MPQ) and a visual analogue scale (VAS, ranging 0–100) to measure pain intensity were recorded. The average VAS score for pain intensity was 73 in the SCS group and 67 in the control group at baseline. After 6 months of treatment, the average VAS score was significantly reduced to 31 in the SCS group (P < .001) and remained 67 (P = .97) in the control group. The SF‐MPQ and EuroQoL 5D questionnaires also showed that patients in the SCS group, unlike those in the control group, experienced reduced pain and improved health and quality of life after 6 months of treatment. In patients with refractory painful diabetic neuropathy, spinal cord stimulation therapy significantly reduced pain and improved quality of life.

Long-term superiority of subthalamic nucleus stimulation over pallidotomy in Parkinson disease.

The results of our multicenter randomized controlled trial comparing unilateral pallidotomy with bilateral subthalamic nucleus (STN) stimulation in advanced Parkinson disease (PD) demonstrated that STN stimulation is more effective than pallidotomy up to 1 year postoperatively.1,2 Here we present the 4-year follow-up of this trial.nn### Methods.nnThirty-four patients with advanced PD were randomly assigned to have unilateral pallidotomy or bilateral STN stimulation. Inclusion and exclusion criteria and study methods were described previously.1,2 The 2 assessors were blinded to the treatment allocation during the complete follow-up. For patients allocated to unilateral pallidotomy, the protocol allowed STN stimulation at least 6 months after pallidotomy. Outcome measures were the off and on phase motor Unified Parkinsons Disease Rating Scale (UPDRS) scores,3 dyskinesia severity (Clinical Dyskinesias Rating Scale),4 functional status (activities of daily living [ADL] UPDRS),3 PD Quality of Life questionnaire,5 levodopa equivalent dose,2 and adverse events. Difference in median change scores (4 years follow-up minus baseline) between treatment groups were analyzed using the Mann-Whitney U test or Kruskal-Wallis rank test, when …

Spinal Cord Stimulation With Hybrid Lead Relieves Pain in Low Back and Legs

Objective:u2002 The failed back surgery syndrome (FBSS) is the most common chronic pain syndrome. Whereas it is relatively easy to achieve pain relief in the lower limbs of FBSS patients with spinal cord stimulation (SCS), it is difficult to manage low back pain with SCS. The performance of a paddle‐shaped SCS lead that can be inserted surgically as well as percutaneously (a hybrid lead) was evaluated in a prospective study on the relief of low back pain and leg pain in patients with FBSS.

Is Preoperative Pain Duration Important in Spinal Cord Stimulation? A Comparison Between Tonic and Burst Stimulation

Conflicting data have been published as to whether the success rate of spinal cord stimulation (SCS) is inversely proportional to the time interval from the initial onset of symptoms to implantation. Recently, a new stimulation design called burst stimulation has been developed that seems to exert its effect by modulating both the medial and lateral pain pathways and has a better effect than tonic stimulation on global pain, back pain, and limb pain.

Long term results of unilateral posteroventral pallidotomy for antipsychotic drug induced tardive dyskinesia

Long term results of unilateral posteroventral pallidotomy for antipsychotic drug induced tardive dyskinesia.