Gamma Knife Thalamotomy for Essential Tremor: A Retrospective Analysis.

BACKGROUND: Gamma knife (GK) thalamotomy has been used as a treatment option for essential tremor (ET). Numerous studies on GK use in ET treatment have reported more varied responses and complication rates. METHODS: Data from 27 patients with ET who underwent GK thalamotomy were retrospectively analyzed. The Fahn-Tolosa-Marin Clinical Rating Scale for Tremor, handwriting, and spiral drawing were evaluated. Postoperative adverse events and magnetic resonance imaging findings were also evaluated. RESULTS: The mean age at GK thalamotomy was 78.1 ± 4.2 years. The mean follow-up period was 32.5 ± 19.4 months. The preoperative postural tremor, handwriting, and spiral drawing scores were 3.4 ± 0.6, 3.3 ± 1.0, and 3.2 ± 0.8, respectively, all of which showed significant improvements to 1.5 ± 1.2 (55.9% improvement, P < 0.001), 1.4 ± 1.1 (57.6% improvement, P < 0.001), and 1.6 ± 1.3 (50% improvement, P < 0.001), respectively, at the available final follow-up evaluations. Three patients presented with no improvement in tremor. Six patients presented with adverse effects, including complete hemiparesis, foot weakness, dysarthria, dysphagia, lip numbness, and finger numbness, at the final follow-up period. Two patients presented with serious complications, including complete hemiparesis due to massive widespread edema and chronic encapsulated expanding hematoma. One patient died of aspiration pneumonia following severe dysphagia secondary to chronic encapsulated expanding hematoma. CONCLUSIONS: GK thalamotomy is an efficient procedure for treating ET. Careful treatment planning is necessary to reduce complication rates. The prediction of radiation complications will increase the safety and effectiveness of GK treatment.

Bilateral Radiofrequency Ventral Intermediate Thalamotomy for Essential Tremor.

INTRODUCTION: With the advent of MR-guided focused ultrasound, the importance of the efficacy and safety of bilateral ventral intermediate (Vim) thalamotomy for essential tremor (ET) has increased. However, reports on bilateral Vim thalamotomy for ET remain scarce. METHODS: To review the results and complications of bilateral Vim thalamotomy for the treatment of ET in the upper extremities, we retrospectively analyzed the patients with ET who underwent bilateral Vim thalamotomy with radiofrequency (RF) thermal coagulation. As bilateral simultaneous thalamotomy can cause surgical complications, thalamotomy was performed in stages. The interval between the first and second thalamotomies was 21.3 ± 14.7 months. We evaluated the efficacy using the Clinical Rating Scale for Tremor (CRST) before and after the first and second treatments, respectively. We also evaluated the complications before and after the first and second treatments, respectively. Moreover, we assessed the adverse events. RESULTS: Seventeen patients were included in the study. The mean follow-up period following the second thalamotomy was 29.3 ± 15.0 months. The CRST part A + B scores were 34.9 ± 9.7, 20.8 ± 7.0, and 7.4 ± 6.8 before, following the first (40.4% improvement, p < 0.0001) and second thalamotomies (78.6% improvement, p < 0.0001), respectively. Nine patients presented with prolonged adverse events, including dysarthria, dysgeusia, dysphagia, tongue numbness, unsteady gait, and postural instability at the last available evaluation. All adverse events were mild and did not interfere with the patient's daily activities. DISCUSSION/CONCLUSIONS: Bilateral Vim thalamotomy with RF thermal coagulation was an effective treatment for ET in both upper extremities. Despite most possible complications being mild, additional studies with a larger sample size are required to ensure patient safety.

Magnetic resonance imaging-guided focused ultrasound thalamotomy for essential tremor: 5-year follow-up results.

OBJECTIVE: The objective of this study was to evaluate, at 4 and 5 years posttreatment, the long-term safety and efficacy of unilateral MRI-guided focused ultrasound (MRgFUS) thalamotomy for medication-refractory essential tremor in a cohort of patients from a prospective, controlled, multicenter clinical trial. METHODS: Outcomes per the Clinical Rating Scale for Tremor (CRST), including postural tremor scores (CRST Part A), combined hand tremor/motor scores (CRST Parts A and B), and functional disability scores (CRST Part C), were measured by a qualified neurologist. The Quality of Life in Essential Tremor Questionnaire (QUEST) was used to assess quality of life. CRST and QUEST scores at 48 and 60 months post-MRgFUS were compared to those at baseline to assess treatment efficacy and durability. All adverse events (AEs) were reported. RESULTS: Forty-five and 40 patients completed the 4- and 5-year follow-ups, respectively. CRST scores for postural tremor (Part A) for the treated hand remained significantly improved by 73.3% and 73.1% from baseline at both 48 and 60 months posttreatment, respectively (both p < 0.0001). Combined hand tremor/motor scores (Parts A and B) also improved by 49.5% and 40.4% (p < 0.0001) at each respective time point. Functional disability scores (Part C) increased slightly over time but remained significantly improved through the 5 years (p < 0.0001). Similarly, QUEST scores remained significantly improved from baseline at year 4 (p < 0.0001) and year 5 (p < 0.0003). All previously reported AEs remained mild or moderate, and no new AEs were reported. CONCLUSIONS: Unilateral MRgFUS thalamotomy demonstrates sustained and significant tremor improvement at 5 years with an overall improvement in quality-of-life measures and without any progressive or delayed complications. Clinical trial registration no.: NCT01827904 (ClinicalTrials.gov).

Chronic Encapsulated Expanding Hematoma After Gamma Knife Thalamotomy for Essential Tremor.

There have been no previous reports of chronic encapsulated expanding hematoma after Gamma Knife thalamotomy. The present case underwent Gamma Knife thalamotomy for essential tremor at the age of 78 years. Three- and 12-month posttreatment magnetic resonance imaging (MRI) showed small T2 high-intensity lesions on the target and along with the internal capsule. Hemiparesis developed 17 months after the treatment. Twenty months post treatment, T2-MRI showed a hypointense mass across the target and internal capsule. Gradual expansion of the mass was confirmed on MRI at 26-38 months. A 54-month posttreatment MRI showed marked expansion of the mass with multiple cysts surrounded by a T2-hypointense rim. Gadolinium-enhanced T1-MRI showed partial enhancement of the mass. MRI findings suggested a radiation-induced cavernoma. Hemiparesis, dysesthesia, and pain on the right side of the body persisted even after steroid therapy for several months. Long-term careful observation is necessary after Gamma Knife thalamotomy.

VIM Line Technique for Determining the Ventral Intermediate Location.

AIM: To prove that VIM line technique created by using a mathematical model, can be used to identify the location of the ventral intermediate nucleus of the thalamus (VIM) MATERIAL and METHODS: Eleven patients with Parkinson?s disease (PD) were assessed. To determine the VIM location, 3-T magnetic resonance imaging and stereotactic protocol 128-slice computed tomography were used. The VIM line technique was performed by drawing a line from the end-point of the right external globus pallidus to that of the left external globus pallidus in the intercommissural plane. PD severity was measured using the Unified Parkinson?s Disease Rating Scale (UPDRS). RESULTS: A mathematical model was constructed to describe the VIM line technique for determining the VIM location. UPDRS scores before and after thalamotomy showed a significant decreasing trend (p=0.003). CONCLUSION: The VIM line technique using the mathematical model can be considered a referential method to determine the VIM location. Its effectiveness was demonstrated by decreased UPDRS scores in patients after VIM thalamotomy.

Focused Ultrasound Thalamotomy for Tremor-dominant Parkinson's Disease: A Prospective 1-year Follow-up Study.

Transcranial magnetic resonance (MR)-guided focused ultrasound (FUS) therapy is an emerging and minimally invasive treatment for movement disorders. There are limited reports on its long-term outcomes for tremor-dominant Parkinson's disease (TDPD). We aimed to investigate the 1-year outcomes of ventralis intermedius (VIM) thalamotomy with FUS in patients with TDPD. Patients with medication-refractory TDPD were enrolled and underwent unilateral VIM-FUS thalamotomy. Neurologists specializing in movement disorders evaluated the tremor symptoms and disability using Parts A, B, and C of the Clinical Rating Scale for Tremor (CRST) at baseline and at 1, 3, and 12 months. In all, 11 patients (mean age: 71.6 years) were included in the analysis. Of these, five were men. The median (interquartile range) improvement from baseline in hand tremor score, the total score, and functional disability score were 87.9% (70.5-100.0), 65.3% (55.7-87.7), and 66.7% (15.5-85.1), respectively, at 12 months postoperatively. This prospective study demonstrated an improvement in the tremor and disability of patients at 12 months after unilateral VIM-FUS thalamotomy for TDPD. In addition, there were no serious persistent adverse events. Our results indicate that VIM-FUS thalamotomy can be safely and effectively used to treat patients with TDPD. A randomized controlled trial with a larger cohort and long blinded period would help investigate the recurrence, adverse effects, placebo effects, and longer efficacy of this technique.

Focused Ultrasound Thalamotomy for Refractory Essential Tremor: A Japanese Multicenter Single-Arm Study.

BACKGROUND: Several feasibility studies and a randomized, controlled, multicenter trial have demonstrated the safety and efficacy of unilateral transcranial magnetic resonance-guided focused ultrasound (FUS) lesioning of the ventral intermediate thalamic nucleus in treating essential tremor. OBJECTIVE: To evaluate the safety and efficacy of FUS thalamotomy in a Japanese patient cohort through a prospective, multicenter, single-arm confirmatory trial. METHODS: A total of 35 patients with disabling refractory essential tremor underwent unilateral FUS thalamotomy and were followed up for 12 post-treatment months. Safety was measured as the incidence and severity of treatment-related adverse events. Efficacy was measured as the tremor severity and quality of life improvements using the Clinical Rating Scale for Tremor and Questionnaire for Essential Tremor. RESULTS: The mean skull density ratio (SDR) was 0.47. There was a significant decrease in the mean postural tremor score of the treated hand from baseline to 12 mo by 56.4% (95% CI: 46.7%-66.1%; P < .001), which was maintained at last follow-up. Quality of life improved by 46.3% (mean overall Questionnaire for Essential Tremor score of 17.4 [95% CI: 12.1-22.7]) and there were no severe adverse events. The most frequent adverse event was gait disturbance and all events resolved. CONCLUSION: Unilateral FUS thalamotomy allowed significant and sustained tremor relief and improved the quality of life with an outstanding safety profile. The observed safety and efficacy of FUS thalamotomy were comparable to those reported in a previous multicenter study with a low SDR, and inclusion of the low SDR group did not affect effectiveness.

Predictors of Outcomes After Focused Ultrasound Thalamotomy.

BACKGROUND: Magnetic resonance-guided focused ultrasound thalamotomy (FUS-T) is an emerging treatment for essential tremor (ET). OBJECTIVE: To determine the predictors of outcomes after FUS-T. METHODS: Two treatment groups were analyzed: 75 ET patients enrolled in the pivotal trial, between 2013 and 2015; and 114 patients enrolled in the postpivotal trials, between 2015 and 2016. All patients had medication-refractory, disabling ET, and underwent unilateral FUS-T. The primary outcome (hand tremor score, 32-point scale with higher scores indicating worse tremor) and the secondary outcome variables (Clinical Rating Scale for Tremor Part C score: 32-point scale with higher scores indicating more disability) were assessed at baseline and 1, 3, 6, and 12 mo. The operative outcome variables (ie, peak temperature, number of sonications) were analyzed. The results between the 2 treatment groups, pivotal and postpivotal, were compared with repeated measures analysis of variance and adjusted for confounding variables. RESULTS: A total of 179 patients completed the 12-mo evaluation. The significant predictors of tremor outcomes were patient age, disease duration, peak temperature, and number of sonications. A greater improvement in hand tremor scores was observed in the postpivotal group at all time points, including 12 mo (61.9% ± 24.9% vs 52.1% ± 24.9%, P = .009). In the postpivotal group, higher energy was used, resulting in higher peak temperatures (56.7 ± 2.5 vs 55.6 ± 2.8°C, P = .004). After adjusting for age, years of disease, number of sonications, and maximum temperature, the treatment group was a significant predictor of outcomes (F = 7.9 [1,165], P = .005). CONCLUSION: We observed an improvement in outcomes in the postpivotal group compared to the pivotal group potentially reflecting a learning curve with FUS-T. The other associations of tremor outcomes included patient age, disease duration, peak temperature, and number of sonications.

Three-year follow-up of prospective trial of focused ultrasound thalamotomy for essential tremor.

OBJECTIVE: To test the hypothesis that transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) thalamotomy is effective, durable, and safe for patients with medication-refractory essential tremor (ET), we assessed clinical outcomes at 3-year follow-up of a controlled multicenter prospective trial. METHODS: Outcomes were based on the Clinical Rating Scale for Tremor, including hand combined tremor-motor (scale of 0-32), functional disability (scale of 0-32), and postural tremor (scale of 0-4) scores, and total scores from the Quality of Life in Essential Tremor Questionnaire (scale of 0-100). Scores at 36 months were compared with baseline and at 6 months after treatment to assess for efficacy and durability. Adverse events were also reported. RESULTS: Measured scores remained improved from baseline to 36 months (all p < 0.0001). Range of improvement from baseline was 38%-50% in hand tremor, 43%-56% in disability, 50%-75% in postural tremor, and 27%-42% in quality of life. When compared to scores at 6 months, median scores increased for hand tremor (95% confidence interval [CI] 0-2, p = 0.0098) and disability (95% CI 1-4, p = 0.0001). During the third follow-up year, all previously noted adverse events remained mild or moderate, none worsened, 2 resolved, and no new adverse events occurred. CONCLUSIONS: Results at 3 years after unilateral tcMRgFUS thalamotomy for ET show continued benefit, and no progressive or delayed complications. Patients may experience mild degradation in some treatment metrics by 3 years, though improvement from baseline remains significant. CLINICALTRIALSGOV IDENTIFIER: NCT01827904. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with severe ET, unilateral tcMRgFUS thalamotomy provides durable benefit after 3 years.

Improvement of Writer's Cramp from an Old Lesion in the Contralateral Hemisphere with Transient Gait Disturbance After Thalamotomy.

BACKGROUND: Stereotactic ventro-oral thalamotomy has been performed in cases of focal task-specific dystonia, including writer's cramp, with excellent outcomes. However, no reports have revealed the outcome of ventro-oral thalamotomy in a patient with a contralateral cerebral lesion. We describe a patient with left-hand writer's cramp with an old lesion in the left hemisphere and transient gait disturbance after right ventro-oral thalamotomy. CASE DESCRIPTION: A 43-year-old man had a hemorrhage in the left basal ganglia due to cerebral arteriovenous malformation at 22 years of age, and right hemiparesis remained as a sequela. He developed left-handed writing ability; however, he became aware of the stiffness of his left hand and difficulty in writing. Writer's cramp was diagnosed. Medical treatments were not effective, and right ventro-oral thalamotomy was performed. Although his writing ability improved, he could not walk. After performing rehabilitation, his walking completely improved, reaching the level before surgery, after 3 months, and his writer's cramp was completely cured. CONCLUSIONS: In patients with basal nucleus lesions, gait disturbance may appear transiently after contralateral thalamotomy. It is crucial to fully explain the potential complications, particularly in relation to temporal gait disturbances, and obtain informed consent.

Safety and long-term efficacy of ventro-oral thalamotomy for focal hand dystonia: A retrospective study of 171 patients.

OBJECTIVE: To report the safety and long-term efficacy of ventro-oral thalamotomy for 171 consecutive patients with task-specific focal hand dystonia. METHODS: Between October 2003 and February 2017, 171 consecutive patients with task-specific focal hand dystonia underwent unilateral ventro-oral thalamotomy. Etiologies included writer's cramps (n = 92), musician's dystonias (n = 58), and other occupational task-related dystonias (n = 21). The task-specific focal hand dystonia scale was used to evaluate patients' neurologic conditions (range 1-5, high score indicated a better condition). The scores before surgery; at 1 week, 3 months, and 12 months postoperatively; and the last available follow-up period were determined. Postoperative complications and postoperative recurrence were also evaluated. RESULTS: The scores before surgery; at 1 week (1.72 ± 0.57, 4.33 ± 0.85 [p < 0.001]), 3 months (4.30 ± 1.06 [p < 0.001]), and 12 months (4.30 ± 1.13 [p < 0.001]); and the last available follow-up (4.39 ± 1.07 [p < 0.001]) postoperatively improved. The mean clinical follow-up period was 25.4 ± 32.1 months (range: 3-165). Permanent adverse events developed in 6 patients (3.5%). Eighteen patients developed recurrent dystonic symptoms postoperatively. Of these 18 patients, 9 underwent ventro-oral thalamotomy again, of which 7 achieved improvement. CONCLUSION: Ventro-oral thalamotomy is a feasible and reasonable treatment for patients with refractory task-specific focal hand dystonias. Prospective, randomized, and blinded studies are warranted to clarify more accurate assessment of the safety and efficacy of ventro-oral thalamotomy for task-specific focal hand dystonia. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with task-specific focal hand dystonia, ventro-oral thalamotomy improves dystonia.

Pallidothalamic Tractotomy for Parkinson Disease with 1-Year Follow-Up: A Case Report.

BACKGROUND: The pallidothalamic tract connects the globus pallidus internus and the ventrolateral portion of the thalamus, and ablation of the pallidothalamic tract (pallidothalamic tractotomy [PTT]) reportedly exerts antiparkinsonian effects. However, the detailed clinical course has not yet been elucidated. Here, we present the first single case report of PTT performed in a patient with Parkinson disease, with 1-year follow-up. CASE DESCRIPTION: The patient was a 68-year-old woman with Parkinson disease. After 14 years of receiving oral medication, she experienced the "wearing-off" phenomenon. Levodopa (300 mg/day) was required to maintain daily activities. Rigidity and peak-dose dyskinesia were predominantly observed in the right side of her body. In addition, she demonstrated right foot dystonia with pain. The preoperative Unified Parkinson Disease Rating Scale part 1, 2 (off medication/on medication), 3 (off medication/on medication), and 4 scores were 7, 26/4, 41/23, and 13, respectively. Further, the preoperative Unified Dyskinesia Rating Scale and Parkinson Disease Questionnaire-39 scores were 102 and 46, respectively. She underwent left-sided PTT, and no perioperative complications were observed. At 1 year postoperatively, daily administration of levodopa (200 mg) was maintained without an "off" condition all day. The 1-year Unified Parkinson Disease Rating Scale part 1, 2, 3, and 4 scores were 5, 9/1, 20/12, and 5, respectively. In addition, the 1-year Unified Dyskinesia Rating Scale and Parkinson Disease Questionnaire-39 scores were 20 and 20, respectively. CONCLUSIONS: We present a rare case of PTT performed in a patient with Parkinson disease. PTT might be useful in patients who do not desire device implantation.

Neurological adverse event profile of magnetic resonance imaging-guided focused ultrasound thalamotomy for essential tremor.

BACKGROUND: Magnetic resonance imaging-guided focused ultrasound thalamotomy is approved by the U.S. Food and Drug Administration for treatment of essential tremor. Although this incisionless technology creates an ablative lesion, it potentially avoids serious complications of open stereotactic surgery. OBJECTIVE: To determine the safety profile of magnetic resonance imaging-guided focused ultrasound unilateral thalamotomy for essential tremor, including frequency, and severity of adverse events, including serious adverse events. METHODS: Analysis of safety data for magnetic resonance imaging-guided focused ultrasound thalamotomy (186 patients, five studies). RESULTS: Procedure-related serious adverse events were very infrequent (1.6%), without intracerebral hemorrhages or infections. Adverse events were usually transient and were commonly rated as mild (79%) and rarely severe (1%). As previously reported, abnormalities in sensation and balance were the commonest thalamotomy-related adverse events. CONCLUSION: The overall safety profile of magnetic resonance imaging-guided focused ultrasound thalamotomy supports its role as a new option for patients with medically refractory essential tremor. © 2018 International Parkinson and Movement Disorder Society.

A prospective trial of magnetic resonance-guided focused ultrasound thalamotomy for essential tremor: Results at the 2-year follow-up.

OBJECTIVE: Magnetic resonance guided focused ultrasound (MRgFUS) has recently been investigated as a new treatment modality for essential tremor (ET), but the durability of the procedure has not yet been evaluated. This study reports results at a 2- year follow-up after MRgFUS thalamotomy for ET. METHODS: A total of 76 patients with moderate-to-severe ET, who had not responded to at least two trials of medical therapy, were enrolled in the original randomized study of unilateral thalamotomy and evaluated using the clinical rating scale for tremor. Sixty-seven of the patients continued in the open-label extension phase of the study with monitoring for 2 years. Nine patients were excluded by 2 years, for example, because of alternative therapy such as deep brain stimulation (n = 3) or inadequate thermal lesioning (n = 1). However, all patients in each follow-up period were analyzed. RESULTS: Mean hand tremor score at baseline (19.8 ± 4.9; 76 patients) improved by 55% at 6 months (8.6 ± 4.5; 75 patients). The improvement in tremor score from baseline was durable at 1 year (53%; 8.9 ± 4.8; 70 patients) and at 2 years (56%; 8.8 ± 5.0; 67 patients). Similarly, the disability score at baseline (16.4 ± 4.5; 76 patients) improved by 64% at 6 months (5.4 ± 4.7; 75 patients). This improvement was also sustained at 1 year (5.4 ± 5.3; 70 patients) and at 2 years (6.5 ± 5.0; 67 patients). Paresthesias and gait disturbances were the most common adverse effects at 1 year-each observed in 10 patients with an additional 5 patients experiencing neurological adverse effects. None of the adverse events worsened over the period of follow-up, and 2 of these resolved. There were no new delayed complications at 2 years. INTERPRETATION: Tremor suppression after MRgFUS thalamotomy for ET is stably maintained at 2 years. Latent or delayed complications do not develop after treatment. Ann Neurol 2018;83:107-114.

Magnetic Resonance Imaging-guided Focused Ultrasound Thalamotomy for Parkinson's Disease.

Thalamotomy is effective in treating refractory tremor in Parkinson's disease (PD). We herein report a PD patient who underwent left ventral intermediate nucleus and ventro oralis posterior nucleus thalamotomy using magnetic resonance imaging-guided focused ultrasound (MRgFUS). Right-side resting tremor and rigidity were abolished immediately following the ultrasound energy delivery. In addition, left-side resting tremor and rigidity also improved. No adverse events occurred during the procedure. We observed the exacerbation of bradykinesia, which might have been caused by edema around the target. This is the first report of thalamotomy using MRgFUS for PD patient from Japan. Further investigations concerning the efficacy and safety of this procedure are necessary.

Novel Use of the Leksell Gamma Frame for Stereotactic Biopsy of Posterior Fossa Lesions.

BACKGROUND: Stereotactic transcerebellar biopsies of brainstem tumors have often been reported. The Leksell frame or Cosman-Roberts-Wells frame is often used in transcerebellar approaches. However, to access lesions via the cerebellum, these frames should be secured as inferiorly on the cranium as possible, which can require exaggerated neck flexion and limit the flexible trajectory to the target. To overcome these disadvantages, we have devised a new way to use the Leksell frame for transcerebellar approaches. METHODS: The frame was fixed to the upper part of the head and arc support by attaching the frame upside down, which gives surgeons a wide operative field and permits flexible trajectory planning. RESULTS: Under local anesthesia, the surgery was performed in a sitting position. Air was observed in the target site on postoperative computed tomography and magnetic resonance imaging, which confirmed that a specimen had been successfully sampled from the site as planned. CONCLUSIONS: Our devised transcerebellar approach provided a generous operative field and a flexible trajectory, which enabled minimally invasive biopsy of a posterior fossa lesions to be performed in a short amount of time with the patient under local anesthesia.

Improvement of Table Tennis Dystonia by Stereotactic Ventro-Oral Thalamotomy: A Case Report.

BACKGROUND: Task-specific focal dystonia, such as writer's cramp and musician's cramp, is a type of dystonia that affects performance of particular tasks. Such movement disorders have been treated with stereotactic ventro-oral (Vo) thalamotomy with excellent outcomes. However, there has been no previous report of treatment of sport-related or athlete's dystonia by means of stereotactic surgery. We treated a patient with table tennis-related dystonia with Vo thalamotomy, and evaluated the outcome. CASE DESCRIPTION: A 20-year-old, female, left-handed table tennis player complained of difficulty hitting a ping-pong ball. She started playing table tennis at 8 years of age, practiced for more than 4 hours every day, and participated in national tournaments. Abnormal flexion of the left wrist when hitting a ball became apparent when she was 19 years old. The abnormal movement emerged on the forehand stroke and, subsequently, on the backhand, until finally she could not continue playing. The diagnosis was task-specific focal dystonia that did not recover with medication. She visited our hospital and underwent right Vo thalamotomy. The surgery was performed using local anesthesia, with the patient swinging a paddle during stimulation and coagulation of the thalamus. Her symptoms had improved completely the day after surgery, such that she was able to participate in tournaments again. CONCLUSIONS: We applied Vo thalamotomy for the successful treatment of athlete's dystonia, suggesting that this condition has an underlying mechanism similar to that of other task-specific focal dystonias. This provides new hope to patients with athlete's dystonia refractive to other therapies.

A Randomized Trial of Focused Ultrasound Thalamotomy for Essential Tremor.

BACKGROUND: Uncontrolled pilot studies have suggested the efficacy of focused ultrasound thalamotomy with magnetic resonance imaging (MRI) guidance for the treatment of essential tremor. METHODS: We enrolled patients with moderate-to-severe essential tremor that had not responded to at least two trials of medical therapy and randomly assigned them in a 3:1 ratio to undergo unilateral focused ultrasound thalamotomy or a sham procedure. The Clinical Rating Scale for Tremor and the Quality of Life in Essential Tremor Questionnaire were administered at baseline and at 1, 3, 6, and 12 months. Tremor assessments were videotaped and rated by an independent group of neurologists who were unaware of the treatment assignments. The primary outcome was the between-group difference in the change from baseline to 3 months in hand tremor, rated on a 32-point scale (with higher scores indicating more severe tremor). After 3 months, patients in the sham-procedure group could cross over to active treatment (the open-label extension cohort). RESULTS: Seventy-six patients were included in the analysis. Hand-tremor scores improved more after focused ultrasound thalamotomy (from 18.1 points at baseline to 9.6 at 3 months) than after the sham procedure (from 16.0 to 15.8 points); the between-group difference in the mean change was 8.3 points (95% confidence interval [CI], 5.9 to 10.7; P<0.001). The improvement in the thalamotomy group was maintained at 12 months (change from baseline, 7.2 points; 95% CI, 6.1 to 8.3). Secondary outcome measures assessing disability and quality of life also improved with active treatment (the blinded thalamotomy cohort)as compared with the sham procedure (P<0.001 for both comparisons). Adverse events in the thalamotomy group included gait disturbance in 36% of patients and paresthesias or numbness in 38%; these adverse events persisted at 12 months in 9% and 14% of patients, respectively. CONCLUSIONS: MRI-guided focused ultrasound thalamotomy reduced hand tremor in patients with essential tremor. Side effects included sensory and gait disturbances. (Funded by InSightec and others; ClinicalTrials.gov number, NCT01827904.).