During thalamotomy, we have to use the various kinds of brain reference points. From 1989 to 1992, the authors performed streotactic thalamotomy or pallidotomy in 169 patients suffering from tremor. We measured and estimated the important intracerebral reference points. These data were very meaningful for stereotactic functional neurosurgery in the Korean medical community because it is obtained from Korean people. We have also estimated the average location of targets for tremor submission.
Brain ; Humans ; Neurosurgery ; Pallidotomy ; Statistics as Topic* ; Tremor

Stereotactic thalamotomy has traditionally provided good relief of tremor for patients with intractable tremor dominant in Parkinson's disease. However bradykinesia, dyskinesia and rigidity are less reliably treated with this technique. Although posteroventral pallidotomy(PVP) can alleviate dyskinesias appendicular bradykinesia and rigidity, tremor may not be completely ameliorated. Between January 1993 and May 1997, the authors performed posteroventral pallidotomy(PVP) on 69 patients with Parkinson's disease who had bradikinesia, rigidity, drug induced dyskinesia and tremor. Of these patients who had only PVPs 17(25%) patients had severe tremor, 20(29%) patients moderate tremor and 32(46 %) patients mild or no tremor after the surgery. We have combined ventrolateral thalamotomy(VLT ) and PVP in 37 patients with moderate to severe tremor. Of the 37 patients, who had both PVP and VLT, 27(73%) patients showed good improvement, and fair improve-ment in 10(27%). Except for 6 cases with transient dysarthria we did not encounter any other operative complications from the ipsilateral combined PVP and VLT. The combination of the two procedures appear to provide excellent relief for the majority of symptoms in patients suffering from advanced Parkinsons disease with rigidity bradykinesia, dyskinesia and tremor.
Dysarthria ; Dyskinesias ; Humans ; Hypokinesia ; Pallidotomy* ; Parkinson Disease* ; Tremor

The authors report the surgical results of thalamotomy and pallidotomy, performed at our hospital between 1983 and 1993 for the treatment of Parkinson's disease. The series included a retrospective analysis of 156 patients with this condition by stereotactic ventrolateral(VL) thalamotomy(126 patients, 138 thalamotomies) and posterolateral pallidotomy(30 patients, 30 pallidotomies). Each patient was followed up postoperatively, for one year. Among those who underwent the stereotactic VL thalamotomy, 136/138 procedures(99%) led to improvement of tremor, and 83/138(60%) resulted in reduced rigidity. Stereotactic posterolateral pallidotomy, led to improvement of bradykinesia after 27/30 procedures(90%), of rigidity after 22/30(73%) and of tremor after 13/30(43%). Drug-induced dyskinesia showed a 42% improvement in the thalamotomy series and a 93% improvement in the pallidotomy series; the difference between the two series was significant(p<0.001). The patients themselves and their relatives used the Hoehn & Yahr staging scale to assess postoperative improvement in disability, and according to the results, 91/126 patients(72%) in the thalamotomy series and 26/30(87%) in the pallidotomy series showed improvement. In the thalamotomy series, there was a significantly higher improvement in disability for preoperative groups I and II(Hoehn & Yahr staging scale) than for groups III and IV(p<0.029), while in the pallidotomy series, there was no statistically significant difference in postoperative improvement between these same groups(p>0.557). In addition, for groups with greater preoperative disability(Hoehn & Yahr staging, groups III and IV), improvement was more likely after pallidotomy than after thalamotomy. In the pallidotomy series, dysphasia was the only serious complication and this was seen after 20% of procedures. In the thalamotomy series, however, complications included hypotonia(24%), transient confusion(19%), transient dysphasia(11%), permanent dysarthria(7%), subjective numbness(4%) and epileptic seizure(3%). The authors believe that posterolateral pallidotomy is much more effective than VL thalamotomy for the control of Parkinsonian bradykinesia and rigidity, but that thalamotomy is still a useful surgical option for the control of Parkinsonian tremor.
Aphasia ; Dyskinesia, Drug-Induced ; Humans ; Hypokinesia ; Pallidotomy* ; Parkinson Disease* ; Retrospective Studies ; Tremor

OBJECTIVES: For Parkinsonian patients who had not reacted favorably on drug therapy are good candidate for ventroposterolateral pallidotomy, although not curative. We studied these patients after unilateral pallidotomy, to confirm the effectiveness and safety of this procedure. METHODS: We evaluated the 17 patients with idiopathic Parkinson's diesease who had undergone unilateral posteroventral pallidotomy. All patients responded to levodopa initially. Mean age was 55 years(38-75years), and mean duration of disease was 9.8 years(3-20years). Pre-and postoperative evaluation at 3 month intervals included Unified Parkinson's Disease Rating scale(UPDRS) scoring, Hoehn and Yahr(H and Y) staging, and neuropsychological examinations. RESULTS: Pallidotomy significantly improved parkinsonian symptom(tremor, rigidity, bradykinesia, dyskinesia, sensory symptom). Nine of 10 patients who showed dyskinesia preoperatively significant improvement. The mean dose of levodopa in 9 patients was lowered. The mean H and Y score and UPDRS score were improved in on and/or off time in 15 patients. Among patients who were not improved, one patient worsened, and the others showed no change. The mean overall UPDRS off score changed from 76 preoperatively to 44(33%) at 6 months and from 70 to 52(25%) at 1 year. Transient surgical morbidity was showen in four patients and included dysarthria, hypotonia and confusion. CONCLUSION: We conclude that pallidotomy is safe and effective in patients who have levodopa-reponsive parkinsonism with severe symptom fluctuation. Unilateral pallidotomy also considered helpful to ipsilateral symptom. Unilateral pallidotomy can improve all of parkinsonian's symptom and allow to reduce the levodopa medication. Most of patients show satisfactory results.
Drug Therapy ; Dysarthria ; Dyskinesias ; Humans ; Hypokinesia ; Levodopa ; Muscle Hypotonia ; Pallidotomy* ; Parkinson Disease ; Parkinsonian Disorders

OBJECTIVE: An usefulness and an accuracy of Neurosurgery Simulator(R)(NSS(R)) is evaluated for the clinical applications. The NSS(R) is a surgical planning tool for stereotactic and functional neurosurgery, recently developed in Korea. METHODS: Thirty-four surgical cases, performed with the NSS(R) from October 1999 to April 2002, were analyzed. The accuracy was examined by comparing the actual lesion with the planned target. The usefulness was discussed with time consuming factor and convenience for surgical steps. Results of surgical outcome were also reviewed. RESULTS: The precise coordinates of surgical target is directly acquired by designating an anatomical lesion on the magnetic resonance image with NSS(R) due to auto recognition algorithm of the fiducials on the MRI image. The correctness is confirmed again by examining the anatomical lesion with superimposing the Schaltenbrand-Wahren atlas on the image directly. Among eleven cases of the thalamotomy for tremors, five cases resulted in complete resolution, the remaining five patients showed significant reduction of tremors. Improvement of ADL and UPDRS was recorded in all 6 Parkinson's disease patients who had undergone pallidotomy. Seventy five percent of patient in pain and psychosurgery resulted in improvements. The NSS(R) achieved 100% accuracy in calculating stereotactic biopsy coordinates. There was no deviation in guiding surgical trajectory. There was no significant surgical complication. CONCLUSION: Stereotactic and functional neurosurgery performed with the assistance of the NSS(R) is relatively safe and accurate.
Activities of Daily Living ; Biopsy ; Humans ; Korea ; Magnetic Resonance Imaging ; Neurosurgery* ; Pallidotomy ; Parkinson Disease ; Psychosurgery ; Tremor

OBJECTIVE: The exact position of the lesion during the pallidotomy is critical to obtain the clinical improvement of parkinson's disease without damage to surrounding structure. Ventriculogrphy, CT(computed tomograpy) or MRI(magnetic resonance imaging) have been used to determine the initial coordinates of stereotactic target for pallidotomy. The goal of this study was to determine whether microelectrode recording significantly improves the neurophysiologic localization of the target obtained from MRI. METHODS: Twenty patients were studied. They underwent a unilateral pallidotomy. Leksell frame was applied and T1 axial images parallel to the AC-PC(anterior commissure-posterior commissure) plane using a 1.5 Tesla MRI with 3mm slice thickness were obtained. Anteroposterior coordinate of target was chosen at 2mm in front of the midcommissural point and lateral coordinate between 19 and 22mm from the midline. The vertical coordinate was calculated on coronal slice using a fast spin echo inversion recovery sequence(FSEIR) related to the position of the choroidal fissure and ranged over 4-5mm below the AC-PC plane. Confirmation of the anatomical target was done on axial slices using the same FSEIR sequence. Microrecording was done at the pallidum contralateral to the symptomatic side using an electrode with a tip diameter of 1nm diameter tip and 1.1-1.4 mOhm impedance at 1000Hz. Electrophysiologic localization of the target was also confirmed intraoperatively by macrostimulation. RESULTS: Microrecording techniques were reliable to define the transition from the base of the pallidum which was characterized by the disappearance of spike activity and by the change of the audible background activity. Signals from high amplitude neurons firing at 200-400Hz were recorded in the pallidal base. X, Y and Z coordinates of target obtained from the MRI were within 1mm from the X, Y, Z coordinates obtained with microrecording in 16 patients (80%), 15 patients(75%), 10 patients(50%) respectively. The difference of Y coordinate between on MRI and on microrecording was 4mm in only one patient. CONCLUSION: The MRI was accurate to localize the target within 1mm of the error from microrecording target in 70% of the patients. 4mm discrepancy was observed only once. We conclude that MRI alone can be used to determine the target for pallidotomy in most patients. However, microrecording technique can still be extremely valuable in patents with aberrant anatomy or unusual MRI coordinates. We also consider physiologic confirmation of the target using macrostimulation to be mandatory in all cases.
Choroid ; Electric Impedance ; Electrodes ; Fires ; Humans ; Magnetic Resonance Imaging* ; Microelectrodes ; Neurons ; Pallidotomy* ; Parkinson Disease*

OBJECTIVE: The authors present a clinical analysis to determine the clinical efficacy of unilateral palliotomy for Parkinson's disease without microelectrode recording procedure and to review the surgical technique, based on the anatomical landmark using magnetic resonance(MR) image. METHODS: Twenty-seven patients were retrospectively studied with extensive neurological examinations including Unified Parkinson's Disease Rating Scale(UPDRS) in 'levodopa-on and -off' tate before and at 6 and 12 months following MRI-guided pallidotomy. Lesion location was characterized using thin sliced MR image and measured on axial slice of TOF image. Lesion was performed with radiofrequency lesion generator. RESULTS: Final surgical target was 2.7+/-0.3mm in front of the intercommissural point, 4.0+/-1mm below the imtercommissural line, and 20.2+/-1.4mm lateral to the midline of the third ventricle. Significant improvements were observed in the total UPDRS scores and motor scores. And there was no significant postoperative complication and sequale except transient paresis(2 cases) and dysarthria(1 case). CONCLUSION: Steretotactic MR image guided pallidotomy with macrostimulation for the patients with Parkinson's disease is safe with minimal morbidity and significantly reduces the disabilities of Parkinson's disease.
Humans ; Microelectrodes ; Neurologic Examination ; Pallidotomy* ; Parkinson Disease* ; Postoperative Complications ; Retrospective Studies ; Third Ventricle

Glutaric aciduria type 1 is an inborn error of lysine, hydroxylysine, and tryptophan metabolism caused by deficiency of glutaryl-coenzyme A dehydrogenase. The disease often appears in infancy with encephalopathy episode that results in acute basal ganglia and white matter degeneration. The majority of patients develop a dystonic-dyskinetic syndrome. This reports 6year-old boy who had been done previous gastrostomy due to swallowing difficulty underwent bilateral pallidotomy with intraoperative electromyography(EMG) monitoring for disabling dystonia. Intraoperative EMG was used to assess stimulation thresholds required for capsular responses and muscle tone. Surface EMG electrodes were placed on the face and cricopharyngeal muscles. Exact target were directly modified according to MRI-visualized anatomy. EMG response was consistently seen prior to visual observation of muscle activity. The surgery improved dystonic symptoms without swallowing difficulty.
Basal Ganglia ; Deglutition ; Dystonia* ; Electrodes ; Gastrostomy ; Glutaryl-CoA Dehydrogenase ; Humans ; Hydroxylysine ; Lysine ; Male ; Metabolism ; Muscles ; Pallidotomy* ; Tryptophan

OBJECTIVE: Pallidotomy is known to improve the symptoms of idiopathic Parkinson, s disease (PD), motor fluctuations and dyskinesia related to levodopa therapy. Previous studies reported significantly higher complication rates associated with bilateral pallidotomy than unilateral pallidotomy. The authors assess the safety and clinical outcomes of bilateral pallidotomy for advanced PD. METHODS: Simultaneous bilateral pallidotomy was performed in eight patients with advanced PD between January 1, 2001 and December 31, 2001. All patients underwent lesion making in posteroventral site of internal globus pallidus. The target was localized using macroelectrode stimulation and MRI guided stereotactic technique. The lesions were made by radiofrequency currents. RESULTS: Among eight cases, seven had severe disabling dyskinesias. Compared with baseline scores, the values of dyskinesia after surgery was significantly decreased (P<0.05) for up to 1 year. The mean score changed from 4.4+/-2.1 to 0.3+/-0.5. According to Unified Parkinson's Disease Rating Scale (UPDRS), the mean motor score in off period, which was 38.3+/-13.8 was significantly decreased for 6 months (P<0.05). The ADL (on/off) scores and motor "on" scores of UPDRS were unchanged or deteriorated to 12 months after surgery. There was no apparent adverse effect after surgery in all patients. Only transient mild dysphagia happened in one patient. CONCLUSION: Simultaneous bilateral pallidotomy in advanced PD appears to be effective and safe, particularly in reducing the dyskinesia; in our experience, the side effects are not as high as reported by other groups.
Activities of Daily Living ; Deglutition Disorders ; Dyskinesias ; Globus Pallidus ; Humans ; Levodopa ; Magnetic Resonance Imaging ; Pallidotomy* ; Parkinson Disease* ; Stereotaxic Techniques

OBJECTIVE: This study is designed to evaluate the usefulness of the cutaneous external landmarks in the application of a Leksell stereotactic frame for functional stereotactic surgery. METHODS: Surgical procedures included thalamotomy in 12 and pallidotomy in 4. Thalamotomy and later pallidotomy were performed in one. In application of the Leksell stereotactic frame, the authors used the cutaneous external landmarks including: (1) the pupil and the external acoustic meatus in group I, (2) the pupil and the crus of the helix in group II, (3) the lateral canthus, the crus of the helix, and inferior crura of antihelix in group III. This procedure was done for obtaining magnetic resonance(MR) images showing anterior and posterior commissure in the same axial scan. The targets were Vim for thalamotomy and GPi for pallidotomy. RESULTS: All MR images in group I, II, and III showed anterior and posterior commissures in the same axial scans except for two patients (17.7%) in group I. The MRI coordinate was accurate to localize the target within 1mm of the difference from electrophysiologic target in 76% of the patients. After surgery, a significant improvement was noticed in tremor scale and global outcome scale (p<0.05), but not in total unified parkinson disease rating scale score and Hoehn and Yahr stage (p>0.05). Transient postoperative complications including motor aphasia and hemihypesthesia were noticed in one each, which returned normal in 3 months. CONCLUSION: The cutaneous external landmarks are of value in applying Leksell stereotactic frame for obtaining magnetic resonance images, essentially showing anterior and posterior commissure. This method is also useful in saving total operation time, making patients comfortable, as well as cost effectiveness.
Aphasia, Broca ; Cost-Benefit Analysis ; Ear Canal ; Humans ; Magnetic Resonance Imaging ; Pallidotomy ; Parkinson Disease ; Postoperative Complications ; Pupil ; Tremor