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ABSTRACT: The intercommissural line joining the anterior and posterior commissures defines stereotactic coordinate systems used in functional neurosurgical procedures. Such coordinate systems are generally accepted in humans and nonhuman primate experimental settings and provide high stereotactic precision and reproducibility. The ethical concern surrounding the use of nonhuman primates has motivated and helped popularize the use of the Göttingen minipig as an alternative experimental model for experimental functional neurosurgery. We investigated the position and variability of the intercommissural line in the minipig brain using in vivo MRI. From these data, standard coordinates for the minipig basal ganglia were estimated. We found the variability of the intercommissural line to be small in the Göttingen minipig and the variability of the basal ganglia structures to the mid-commissural point to be minor.
Stereotactic and Functional Neurosurgery 04/2010; 88(3):138-46. · 1.85 Impact Factor
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ABSTRACT: The Göttingen minipig is increasingly used as an animal model in experimental neuroscience as a much needed alternative to non-human primates. Accurate spatial targeting in this species in vivo is challenging, and most clinically available magnetic resonance imaging (MRI) protocols do not provide sufficient spatial resolution for this purpose. Thus, the aim of this study was to develop an in vivo pre-operative MRI protocol allowing direct visualization of individual nuclei of major interest in the minipig brain.
Three Göttingen minipigs underwent MRI using an inversion-recovery fast spin-echo sequence that was optimized with regards to the following parameters: inversion time, relaxation time, echo time and spatial and temporal resolution, giving a scan duration acceptable for the tight schedule usually employed in a neurosurgical procedure. The most optimal pulse sequence was applied in 8 Göttingen minipigs and the anatomical structures were identified.
High-resolution images with excellent contrast were acquired, presenting negligible geometric distortions. Minor flow artifacts from the large neck vessels generated the most prominent artifact. Determination of coordinates necessary in experimental neurosurgery in the Göttingen minipig was considerably improved with this MRI protocol.
Brain research bulletin 02/2009; 79(1):41-5. · 2.18 Impact Factor
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Ugeskrift for laeger 11/2003; 165(42):4038-9.
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ABSTRACT: We present the efficacy and side effects of bilateral deep brain stimulation (DBS) of the subthalamic nuclei (STN) performed with a more simplified surgical procedure than described by the Grenoble group. A consecutive series of 26 patients with advanced and levodopa-responsive Parkinson's disease and motor complications was evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) part I-VI, timed tests, and a patient diary for 2 days concerning on-off phenomenon and dyskinesias. At 3 months, evaluation of stimulation by the UPDRS motor score was performed in a double-blind manner and a significant improvement of 57% was found. The results 12 months after surgery off medication showed significant improvement in both UPDRS motor score and activities of daily living of 64% and, on medication, a significant reduction of 86% in duration of dyskinesias and 83% in duration of off-periods. Reduction in medication was less than for other groups, probably because we used smaller doses of levodopa before the operation. No serious side effects were encountered. When the patients are carefully selected and followed up, bilateral DBS of STN is a significant progress in treatment of advanced idiopathic Parkinson's disease with levodopa-induced motor complications.
Movement Disorders 08/2002; 17(4):693-700. · 4.51 Impact Factor
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ABSTRACT: In a retrospective study, changes in baclofen dose and complication frequency were recorded in 79 patients with intrathecal baclofen administration and the effect on nightly muscle spasms was measured over a mean observation period of 34 months, during which time an increase in the daily dose of baclofen during the first 1--1-1/2 years is notified. On subsequent pump fillings the daily dose of baclofen remained stable in the group of non-multiple sclerosis patients. In contrast, the group of multiple sclerosis patients showed a steady increase in their daily dose of baclofen. We found a frequency of complications of 0.014 monthly often due to catheter problems. There was a significant decrease in numbers of nightly muscle spasms in an 8 h recording period from 77+/-20 preoperatively and 9+/-3 (P=0.02) 3 months after surgery. The steady increase in the daily dose of baclofen in order to obtain adequate reduction in spasticity and nightly muscle spasms in the first 1--1-1/2 years cannot fully be explained by caution and difficulties in achieving the correct dose, but also indicates that tolerance to baclofen occurs. Complications are often due to infection or catheter problems.
Clinical Neurology and Neurosurgery 06/2002; 104(2):142-5. · 1.58 Impact Factor
