Is MRI a reliable tool to locate the electrode after deep brain stimulation surgery? Comparison study of CT and MRI for the localization of electrodes after DBS

MRI has been utilized to localize the electrode after deep brain stimulation, but its accuracy has been questioned due to image distortion. Under the hypothesis that MRI is not adequate for evaluation of electrode position after deep brain stimulation, this study is aimed at validating the accuracy of MRI in electrode localization in comparison with CT scan. Sixty one patients who had undergone STN DBS were enrolled for the analysis. Using mutual information technique, CT and MRI taken at 6 months after the operation were fused. The x and y coordinates of the centers of electrodes shown of CT and MRI were compared in the fused images to calculate average difference at five different levels. The difference of the tips of the electrodes, designated as the z coordinate, was also calculated. The average of the distance between the centers of the electrodes in the five levels estimated in the fused image of brain CT and MRI taken at least 6 months after STN DBS was 1.33 mm (0.1-5.8 mm). The average discrepancy of x coordinates for all five levels between MRI and CT was 0.56 +/- 0.54 mm (0-5.7 mm), the discrepancy of y coordinates was 1.06 +/- 0.59 mm (0-3.5 mm), and for the z coordinate, it was 0.98 +/- 0.52 mm (0-3.1 mm) (all p values < 0.001). Notably, the average discrepancy of x coordinates at 3.5 mm below AC-PC level, i.e., at the STN level between MRI and CT, was 0.59 +/- 0.42 mm (0-2.4 mm); the discrepancy of y coordinates was 0.81 +/- 0.47 mm (0-2.9 mm) (p values < 0.001). The results suggest that there was significant discrepancy between the centers of electrodes estimated by CT and MRI after STN DBS surgery.Lee JY, 2010, CLIN NEUROL NEUROSUR, V112, P47, DOI 10.1016/j.clineuro.2009.10.008Tagliati M, 2009, NEUROIMAGE, V47, pT53, DOI 10.1016/j.neuroimage.2009.04.044Paek SH, 2008, NEUROSURGERY, V63, P925, DOI 10.1227/01.NEU.0000334045.43940.FBLee JY, 2008, J KOREAN NEUROSURG S, V44, P26, DOI 10.3340/jkns.2008.44.1.26Tisch S, 2007, J NEUROL NEUROSUR PS, V78, P1314, DOI 10.1136/jnnp.2006.109694McClelland S, 2007, J CLIN NEUROSCI, V14, P791, DOI 10.1016/j.jocn.2006.03.032Martinez-Santiesteban FM, 2007, PHYS MED BIOL, V52, P2073, DOI 10.1088/0031-9155/52/8/003Pinto S, 2007, NEUROSURGERY, V60, P285, DOI 10.1227/01.NEU.0000255353.64077.A8Vergani F, 2007, SURG NEUROL, V67, P140, DOI 10.1016/j.surneu.2006.06.054Pollo C, 2007, J NEUROSURG, V106, P36Breit S, 2006, NEUROSURGERY, V58, P83, DOI 10.1227/01.NEU.0000192689.00427.C2COYNE T, 2006, ACT NEUR S, V99, P49Winkler D, 2005, J NEUROL NEUROSUR PS, V76, P1161, DOI 10.1136/jnnp.2004.047373Simon SL, 2005, STEREOT FUNCT NEUROS, V83, P1, DOI 10.1159/000083861Bittar RG, 2005, J CLIN NEUROSCI, V12, P12, DOI 10.1016/j.jocn.2004.03.025MCCLELLAND S, 2005, NEUROSURG FOCUS, V19, pE12Rezai AR, 2004, INVEST RADIOL, V39, P300, DOI 10.1097/01.rli.0000124940.02340.abPollo C, 2004, ACTA NEUROCHIR, V146, P161, DOI 10.1007/s00701-003-0181-4Spiegel J, 2003, J NEUROSURG, V99, P772Counelis GJ, 2003, MOVEMENT DISORD, V18, P1062, DOI 10.1002/mds.10489Hamel W, 2003, J NEUROL NEUROSUR PS, V74, P1036Yelnik J, 2003, J NEUROSURG, V99, P89RAMPINI PM, 2003, J NEUROSURG SCI, V47, P33Uitti RJ, 2002, NEUROSURGERY, V51, P1423, DOI 10.1227/01.NEU.0000036030.73566.4BSaint-Cyr JA, 2002, J NEUROSURG, V97, P1152Voges J, 2002, J NEUROSURG, V96, P269Holtzheimer PE, 1999, NEUROSURGERY, V45, P290Rezai AR, 1999, J NEUROSURG, V90, P583Tronnier VM, 1999, NEUROSURGERY, V44, P118Starr PA, 1998, NEUROSURGERY, V43, P989Limousin P, 1998, NEW ENGL J MED, V339, P1105Dormont D, 1997, AM J NEURORADIOL, V18, P1093Maes F, 1997, IEEE T MED IMAGING, V16, P187, DOI 10.1109/42.563664LIMOUSIN P, 1995, LANCET, V345, P91SUMANAWEERA TS, 1994, NEUROSURGERY, V35, P696ZHANG JX, 1993, AM J NEURORADIOL, V14, P497BROOKS ML, 1992, EPILEPSIA, V33, P888KONDZIOLKA D, 1992, NEUROSURGERY, V30, P402

Long-Term Clinical Outcome of Internal Globus Pallidus Deep Brain Stimulation for Dystonia.

BACKGROUND:GPi (Internal globus pallidus) DBS (deep brain stimulation) is recognized as a safe, reliable, reversible and adjustable treatment in patients with medically refractory dystonia. OBJECTIVES:This report describes the long-term clinical outcome of 36 patients implanted with GPi DBS at the Neurosurgery Department of Seoul National University Hospital. METHODS:Nine patients with a known genetic cause, 12 patients with acquired dystonia, and 15 patients with isolated dystonia without a known genetic cause were included. When categorized by phenomenology, 29 patients had generalized, 5 patients had segmental, and 2 patients had multifocal dystonia. Patients were assessed preoperatively and at defined follow-up examinations postoperatively, using the Burke-Fahn-Marsden dystonia rating scale (BFMDRS) for movement and functional disability assessment. The mean follow-up duration was 47 months (range, 12-84). RESULTS:The mean movement scores significantly decreased from 44.88 points preoperatively to 26.45 points at 60-month follow up (N = 19, P = 0.006). The mean disability score was also decreased over time, from 11.54 points preoperatively to 8.26 points at 60-month follow up, despite no statistical significance (N = 19, P = 0.073). When analyzed the movement and disability improvement rates at 12-month follow up point, no significant difference was noted according to etiology, disease duration, age at surgery, age of onset, and phenomenology. However, the patients with DYT-1 dystonia and isolated dystonia without a known genetic cause showed marked improvement. CONCLUSIONS:GPi DBS is a safe and efficient therapeutic method for treatment of dystonia patients to improve both movement and disability. However, this study has some limitations caused by the retrospective design with small sample size in a single-center

Bilateral Deep Brain Stimulation of the Subthalamic Nucleus under Sedation with Propofol and Fentanyl

<div><p>Awakening during deep brain stimulation (DBS) surgery may be stressful to patients. The aim of the current study was to evaluate the effect on MER signals and their applicability to subthalmic nucleus (STN) DBS surgery for patients with Parkinson’s disease (PD) under sedation with propofol and fentanyl. Sixteen consecutive patients with PD underwent STN-DBS surgery with propofol and fentanyl. Their MER signals were achieved during the surgery. To identify the microelectrodes positions, the preoperative MRI and postoperative CT were used. Clinical profiles were also collected at the baseline and at 6 months after surgery. All the signals were slightly attenuated and contained only bursting patterns, compared with our previous report. All electrodes were mostly located in the middle one third part of the STN on both sides of the brain in the fused images. Six months later, the patients were improved significantly in the medication-off state and they met with less dyskinesia and less off-duration. Our study revealed that the sedation with propofol and fentanyl was applicable to STN-DBS surgery. There were no significant problems in precise positioning of bilateral electrodes. The surgery also improved significantly clinical outcomes in 6-month follow-up.</p></div

The location of electrodes on brain atlas.

<p>Based on the CT-MRI fusion images of the preoperative brain MRI and postoperative brain CT scan taken one month after surgery. The figure shows location of the electrodes plotted onto the human brain atlas of Schaltenbrand and Wahren.</p

Typical bursting patterns from microelectrode recording.

<p>Typical bursting patterns from microelectrode recording.</p

Characteristics of signals on microelectrode recording.

<p>Characteristics of signals on microelectrode recording.</p