Purpose: It remains unclear whether the long-term results of RCTs regarding the outcome of microdiscectomy for lumbosacral radicular syndrome (LSRS) are generalizable. The purpose of this study was... Show morePurpose: It remains unclear whether the long-term results of RCTs regarding the outcome of microdiscectomy for lumbosacral radicular syndrome (LSRS) are generalizable. The purpose of this study was to determine the external validity of the outcome preseneted in RCTs after microdicectomy for LSRS in a patient cohort from a high-volume spine center. Methods: Between 2007 and 2010, 539 patients had a single level microdiscectomy for MRI disk-related LSRS of whom 246 agreed to participate. Questionnaires included visual analogue scores (VAS) for leg pain, RDQ, OLBD, RAND-36 and Likert scores for recovery, leg and back pain. Lumbar re-operation(s) were registered. Results: Mean age was 51.3, and median time of follow-up was 8.0 years. Re-operation occurred in 64 (26%) patients. Unfavorable perceived recovery was noted in 85 (35%) patients, and they had worse leg and back pain than the 161 (65%) patients with a favorable recovery: median VAS for leg pain 28/100 mm versus 2/100 mm and median VAS for back pain 9/100 mm versus 3/100 mm, respectively. In addition, the median RDQ and OLBD scores differed significantly: 9 vs 3 for RDQ and 26 vs 4 for OLBD, respectively (p < 0.001). Conclusion: In this cohort study, the long-term results after microdiscectomy for LSRS were less favorable than those obtained in RCTs, possibly caused by less strict patient selection than in RCTs. Our findings emphasize that patients, who do not meet the same inclusion criteria for surgery as in RCTs, should be informed about the chances of a less favorable result. Show less
Frequin, H.L.; Bot, M.; Dilai, J.; Scholten, M.N.; Postma, M.; Bour, L.J.; ... ; Munckhof, P. van den 2020
Introduction: For deep brain stimulation (DBS) surgery of the subthalamic nucleus (STN) in Parkinson's disease (PD), many centers employ visualization of the nucleus on magnetic resonance imaging ... Show moreIntroduction: For deep brain stimulation (DBS) surgery of the subthalamic nucleus (STN) in Parkinson's disease (PD), many centers employ visualization of the nucleus on magnetic resonance imaging (MRI), intraoperative microelectrode recordings (MER), and test stimulation in awake patients. The value of these steps is a subject for ongoing debate. In the current study, we determined the relative contribution of MRI targeting, multitrack MER, and awake test stimulation in final lead placement during STN DBS surgery for PD. Methods: Data on PD patients undergoing MRI-targeted STN DBS surgery with three-channel MER and awake test stimulation between February 2010 and January 2014 were analyzed to determine in which MER trajectory final leads were implanted and why this tract was chosen. Results: Seventy-six patients underwent implantation of 146 DBS leads. In 92% of the STN, the final leads were implanted in one of the three planned channels. In 6%, additional channels were needed. In 2%, surgery was aborted before final lead implantation due to anxiety or fatigue. The final leads were implanted in the channels with the longest STN MER signal trajectory in 60% of the STN (38% of the bilaterally implanted patients). This was the central channel containing the MRI target in 39% of the STN (18% bilaterally). The most frequently noted reasons why another channel than the central channel was chosen for final lead placement were (1) a lower threshold for side effects (54%) and (2) no or a too short trajectory of the STN MER signal (40%) in the central channel. The latter reason correlated with larger 2D (x and y) errors in our stereotactic method. Conclusions: STN DBS leads were often not implanted in the MRI-planned trajectory or in the trajectory with the longest STN MER signal. Thresholds for side effects during awake test stimulation were decisive for final target selection in the majority of patients. Show less
Bot, M.; Schuurman, P.R.; Odekerken, V.J.J.; Verhagen, R.; Contarino, F.M.; Bie, R.M.A. de; Munckhof, P. van den 2018
BackgroundSubthalamic nucleus (STN) deep brain stimulation effectively improves parkinsonian symptoms. It is hypothesized that distinct functional territories with different neurophysiologic... Show moreBackgroundSubthalamic nucleus (STN) deep brain stimulation effectively improves parkinsonian symptoms. It is hypothesized that distinct functional territories with different neurophysiologic activity within the STN relate to different symptoms.ObjectiveThe aim of the study was to identify distinctive characteristics of STN neuronal activity related to tremor by directly comparing tremor sides with no-tremor sides. In addition, we studied the spatial pattern of frequency distributions within the STN in more detail.MethodsWe analyzed intraoperative STN single/multiunit recordings from 33 tremor sides and 23 no-tremor sides. STN tracks were normalized to a length of 1 and subdivided into eight successive layers. The power spectral density was split into six frequency bands: theta (3-8 Hz), alpha (9-12 Hz), lower beta (13-20 Hz), upper beta (21-30 Hz), lower gamma (31-59 Hz), and upper gamma (60-100 Hz).ResultsTremor sides presented predominant theta frequency oscillations in the most dorsal layers of the STN, whereas in no-tremor sides beta frequencies predominated. Oscillatory activity was stronger in the dorsal STN than in the ventral, and this pattern was specific for frequencies in the theta, alpha, and beta bands, but not in the gamma bands.ConclusionsOur study supports the hypothesis that the presence of tremor is associated with a distinctive neuronal oscillations pattern. In particular, we demonstrate the specificity of the association of theta frequencies in the dorsal STN with tremor. Identification of symptom-specific characteristics of intraoperative microrecordings in the STN may lead to refinement of targeting for each patient, tailored to the specific clinical presentation. (C) 2012 Elsevier Inc. All rights reserved. Show less
Groen, J.L.; Ritz, K.; Contarino, M.F.; Warrenburg, B.P. van de; Aramideh, M.; Foncke, E.M.; ... ; Tijssen, M.A. 2010
Mutations in THAP1, a gene encoding a nuclear pro-apoptotic protein, have been associated with DYT6 dystonia. First reports on the phenotype of DYT6 dystonia show an early onset dystonia with... Show moreMutations in THAP1, a gene encoding a nuclear pro-apoptotic protein, have been associated with DYT6 dystonia. First reports on the phenotype of DYT6 dystonia show an early onset dystonia with predominant cranio-cervical and laryngeal involvement. Here we assessed the frequency and phenotype of THAP1 mutation carriers in a large Dutch cohort of adult-onset >= 26 years) dystonia (n = 388) and early-onset dystonia (n = 67) patients. We describe the phenotype of DYT6 dystonia patients and their response on GPi DBS. Overall, 3 nonsynonymous heterozygous mutations were detected in the early-onset group (4.5%). Two DYT6 families were identified, showing a heterozygous phenotype. All patients had segmental or generalized dystonia, often associated with profound oromandibular and laryngeal involvement. No nonsynonymous mutations were found in patients with adult-onset focal dystonia. Rare synonymous variants were identified in conserved regions of THAP1, two in the adult-onset cervical dystonia group and one in the control group. Four DYT6 dystonia patients were treated with GPi DBS with moderate to good response on motor function but marginal benefit on speech. (C) 2010 Movement Disorder Society Show less
