Tratamiento quirúrgico de la distonía

A pesar de los recientes avances en la comprensión de los circuitos cerebrales involucrados en la distonía, las técnicas quirúrgicas invasivas y no invasivas han fallado en proporcionar un beneficio substancial a los pacientes que sufren de distonía, en comparación con los resultados observados en la enfermedad de Parkinson, no obstante, la lesionectomía, la estimulación cerebral profunda y el ultrasonido enfocado pueden proporcionar mejoría en los casos refractarios al manejo médico.

SUMMARY Despite recent advances in understanding brain circuits involved in dystonia, surgical techniques both invasive and not invasive have fail to provide substantial benefit to patients suffering from dystonia compared to the results seeing in Parkinson's disease, nonetheless, lesionectomy, deep brain stimulation and focused ultrasound can provide relief in medical refractory cases.

Tratamiento quirúrgico de la distonía / Surgical management for dystonia

RESUMEN A pesar de los recientes avances en la comprensión de los circuitos cerebrales involucrados en la distonía, las técnicas quirúrgicas invasivas y no invasivas han fallado en proporcionar un beneficio substancial a los pacientes que sufren de distonía, en comparación con los resultados observados en la enfermedad de Parkinson, no obstante, la lesionectomía, la estimulación cerebral profunda y el ultrasonido enfocado pueden proporcionar mejoría en los casos refractarios al manejo médico.

SUMMARY Despite recent advances in understanding brain circuits involved in dystonia, surgical techniques both invasive and not invasive have fail to provide substantial benefit to patients suffering from dystonia compared to the results seeing in Parkinson's disease, nonetheless, lesionectomy, deep brain stimulation and focused ultrasound can provide relief in medical refractory cases.

Outcome of Gamma Knife Thalamotomy in Patients with an Intractable Tremor

OBJECTIVE: Tremor is a common movement disorder that interferes with daily living. Since the medication for tremor has some limitations, surgical intervention is needed in many patients. In certain patients who cannot undergo aggressive surgical intervention, Gamma Knife thalamotomy (GKT) is a safe and effective alternative. METHODS: From June 2012 to August 2013, 7 patients with an intractable tremor underwent GKT. Four of these 7 patients had medical comorbidities, and 3 patients refused to undergo traditional surgery. Each patient was evaluated with the modified Fahn-Tolosa-Marin tremor rating scale (TRS) along with analysis of handwriting samples. All of the patients underwent GKT with a maximal dose of 130 Gy to the left ventralis intermedius (VIM) nucleus of the thalamus. Follow-up brain MRI was performed after 3 to 8 months of GKT, and evaluation with the TRS was also performed. RESULTS: Six patients showed objective improvement in the TRS score. Excluding one patient who demonstrated tremor progression, there was 28.9% improvement in the TRS score. However, five patients showed subjective improvement in their symptoms. On comparing the TRS scores between follow-up periods of more and less than 4 months, the follow-up TRS score at more than 4 months of GKT was significantly improved compared to that at less than 4 months of GKT. Follow-up MRI showed radiosurgical changes in 5 patients. CONCLUSION: GKT with a maximal dose of 130 Gy to the VIM is a safe procedure that can replace other surgical procedures.

Comparison of analgesic effect following different thalamotomy in rats / 中国神经精神疾病杂志

Background To provide clinical evidence for ablative application by comparison of the analgesic effect following different thalamotomy in rats.Methods Thirty rats were randomly assigned into sham and 4 thalamotomies groups: central medial thalamic nucleus ( CM), parafascicular thalamic nucleus ( PF), ventral posterolateral thalamic nucleus (VPL), and CM +Cigulum (cg). Two μL 10% phenol dissolved in glycerin were used for stereotactic thalamotomy. The thermal pain thresholds before and after procedures were evaluated with the tail stimulate test. The formalin test was carried out in an open field apparatus where the animal formalin-induced responses (licking duration, flexing duration, and flinching frequency of the injected paw) were recorded for 60 min.Results Changes of pain thresholds in all ablative groups were significantly higher than that in the sham group, especially it was higher in VPL group. Differences of the factor thalamotomy were found to be due to the shorter licking in the ablative groups than that in the sham group (P ＜0.01 ), whereas flexing duration and flinching frequency were only slightly affected by thalamotomy. Moreover, licking duration was lower in VPL group than in CM and CM + cg groups ( P ＜0.05), whereas nociceptive responses did not differ between the CM and CM+cg groups (P ＞0.05).Conclusions In acute period, CM, PF, VPL, CM + cg neurolysis all showed to elevate the thermal pain threshold and to reduce the pain-induced behavioral responses related to supraspinal neural circuits (licking of the injected paw). Among them, the damage of VPL might be the most active one. CM + cg damage did not get better antinociceptive effect than single CM ablation.

Efficacy of Thalamotomy and Thalamic Deep Brain Stimulation for the Treatment of Head Tremor

OBJECTIVE: Stereotactic thalamic procedure is well known to be a effective treatment for disabling upper limb tremor of essential tremor. However, the effect of this procedure for head tremor, which is midline symptom of that disease entity, has not been sufficiently established. The authors discuss the result of stereotactic thalamic operations for head tremor of their patients who suffered from essential tremor. METHODS: We evaluated 4 patients of essential tremor who had head tremor combined with both upper limb tremor. One patient underwent unilateral ventralis intermedius thalamotomy, two patients had unilateral Vim deep brain stimulation(DBS) and one patient had unilateral Vim thalamotomy and contralateral DBS. Postoperative results of tremor were evaluated using our proposed scale. RESULTS: Contralateral upper limb tremors to surgical side were markedly resolved in all patients but there was no meaningful effect for head tremor in 3 patients who underwent unilateral thalamic surgery. In a patient having simultaneously unilateral thalamotomy and contralateral DBS, remarkable improvement of head tremor was observed. CONCLUSION: Although it is difficult to evaluate the efficacy of thalamic surgery for axial symptom of essential tremor with a few cases, simultaneous unilateral thalamotomy and contralateral DBS would be expected to induce favorable outcomes for head tremor with significant economical advantages.

Comparison of Thalamotomy with Deep Brain Stimulation in Essential Tremor

OBJECTIVE: Thalamic lesioning and deep brain stimulation(DBS) have proved to be beneficial to the treatment of essential tremor(ET). The authors compared the effects and complications of two modalities. METHODS: A total of 34 patients with ET were treated with ventral intermediate(Vim) nucleus thalamotomy or Vim DBS from May 1999 to May 2003. The procedure of lesioning or stimulation were performed as usual manner with or without microelectrode recording. Postoperatively, utilizing the various combinations of frequency, voltage and pulse width optimized the stimulation. The degree of improvements of tremor and the occurrence of the complications were evaluated postoperatively and at follow-up. RESULTS: There were 38 procedures, including 27 with Vim thalamotomy and 11 with DBS, in 34 patients. Of the thalamotomy group, left Vim lesioning is 25 and right one is 2. Follow-up duration ranged from 12 to 57 months. In the thalamotomy group, the rate of overall good outcome was 88.9% but 12 patients (44.4%) showed permanent adverse effects. In the cases of stimulation, the rate of overall good outcome was 90.9% and two patients had acceptable dysarthria. CONCLUSION: Both Vim thalamotomy and Vim DBS were effective for the treatment of ET, although perioperative adverse effects tended to be higher in patients who had thalamotomy. In cases of DBS, adjustments of stimulation parameters enabled an acceptable position to be achieved with tremor control and unwanted effects.

Thalamotomy without Microelectrode Recording

OBJECTIVE: Tremor, either essential tremor or Parkinsonian tremor, has been effectively and safely treated by lesioning the ventral intermediate(Vim) nucleus of the thalamus with or without mircroelectrode recording. The authors evaluate the treatment outcome of sixteen tremor patients who had been treated with thalamotomy without microelectrode. METHODS: Between September, 2001, and December, 2003, sixteen tremor patients were treated with thalamotomy without microelectrode recording. Twelve patients suffered from Parkinsonian tremor and four patients were essential tremor patients. The male to female ratio was 1.6 to 1 with median age of 59.6 years (range; 39-74 years). Under local anesthesia, a 3mm hole was made using a hand-held twist drill, and the dura mater was penetrated with a 1.2mm sharp drill beat. Radiofrequency(RF) electrode was placed in the Vim nucleus of thalamus. With intraoperative macrostimulation, RF lesion was made. Postoperative CT scan and/or MR imaging was performed to confirm the localization of the target lesioned. Preoperative and postoperative tremor was evaluated with simple tremor severity scale and the development of complications related with the procedure was closely reviewed at the immediate postoperative period and the last follow-up. RESULTS: It produces immediate relief in up to 98.4% of the patients. There were no development of complications related with procedure, all patients discharged one or two days after surgery. CONCLUSION: Vim thalamotomy without microelectrode recording is a safe and effective procedure to control the tremor with minimal morbidity. Intraoperative macroelectrode stimulation safely localizes the Vim nucleus target of the thalamus for the treatment of patients with tremor.

Gamma Knife Radiosurgery for Thalamotomy in Parkinsonian Tremor: Preliminary Report

OBJECTIVE: The authors present a retrospective analysis of gamma knife radiosurgery for thalamotomy for Parkinsonian tremor to determine the efficacy of the procedure, to review radiological findings of radiosurgical lesioning and to assess the risk of complications. METHODS: Radiosurgical thalamotomy with gamma knife was performed in one men and nine women. The target was nucleus ventralis intermedius following classic anatomical landmarks. The median age of the patients was 68 years(range 53-85). A mean radiation dose of 148Gy(range 140-168) was delivered using a 4-mm collimator. Patients were followed for a mean of 35 months(range 21-47). Independent neurological evaluation of tremor was based on the change in the Unified Parkinson's Disease Rating Scale tremor score(UPDRS, question 16, 20, 21) and the subjective satisfaction. The radiological follow-up period of the available five cases ranged from 6 to 13 months(mean 6). RESULTS: Nine patients(90%) showed the decrease in the sum of UPDRS. In the patient's subjective satisfaction, five(50%) showed excellent improvement, three(30%) good improvement and one(10%) mild improvement respectively. No response was observed in one patient. The mean time to onset of improvement was 3.5 months (range 1-14). There were no neurological complications. Follow-up magnetic resonance image showed the target-shaped lesion with a ring enhancement, of which location was matched to that of gamma knife planning. CONCLUSION: Gamma knife radiosurgery for thalamotomy offers acceptable tremor control with minimal risk to patients unsuited for open surgery, however, larger consecutive series and long-term follow-up are mandatory.

Application of Leksell Stereotactic Frame Using External Landmarks in Stereotactic Surgery

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 (p0.05). 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.

Metabolic Alterations in Parkinson's Disease after Thalamotomy, as Revealed by 1H MR Spectroscopy

OBJECTIVE: To determine, using proton magnetic resonance spectroscopy (1H MRS) whether thalamotomy in patients with Parkinson's disease gives rise to significant changes in regional brain metabolism. MATERIALS AND METHODS: Fifteen patients each underwent stereotactic thalamotomy for the control of medically refractory parkinsonian tremor. Single-voxel 1H MRS was performed on a 1.5T unit using a STEAM sequence (TR/TM/TE, 2000/14/20 msec), and spectra were obtained from substantia nigra, thalamus and putamen areas, with volumes of interest of 7-8ml, before and after thalamotomy. NAA/Cho, NAA/Cr and Cho/Cr metabolite ratios were calculated from relative peak area measurements, and any changes were recorded and assessed. RESULTS: In the substantia nigra and thalamus, NAA/Cho ratios were generally low. In the substantia nigra of 80% of patients (12/15) who showed clinical improvement, decreased NAA/Cho ratios were observed in selected voxels after thalamic surgery (p < 0.05). In the thalamus of 67% of such patients (10/15), significant decreases were also noted (p < 0.05). CONCLUSION: Our results suggest that the NAA/Cho ratio may be a valuable criterion for the evaluation of Parkinson's disease patients who show clinical improvement following surgery. By highlighting variations in this ratio, 1H MRS may help lead to a better understanding of the pathophysiologic processes occurring in those with Parkinson's disease.

Familial Writer's Cramp with DYT1 Mutation: A Clinical and Genetic Analysis of a New Kindred

BACKGROUND: Recently a non-Jewish German family with writer's cramp was reported to have DYT1 mutation, expanding the phenotypic spectrum of DYT1. Although functional brain surgery has been tried for generalized dystonia, surgical outcome in focal dystonia patients with DYT1 mutation has not yet been reported. We investigated the clinical features and response to thalamotomy in familial writer's cramp with DYT1 mutation. METHODS: Family members were examined and clinically affected cases were video-taped. For the detection of DYT1 mutation, PCR-RFLP(restriction fragment length polymorphism) and heteroduplex analyses were performed as screening tests. Additional DNA sequencing was performed for the proband case to confirm the GAG deletion. RESULTS: Among this clinically homogeneous non-Jewish Korean family, five members in three generations were affected. Age of onset ranged from 7 to 20 years. Writing difficulty was the initial and the main disabling problem for all the affected individuals. All had the bilateral writer's cramp in succession. Dystonia remained focal and task-specific for the entire period after onset. Unilateral thalamotomy was performed in three patients, with remarkable improvement. Surgical benefit remained unchanged during the follow-up period of 6-8 years. DYT1 mutation cosegregated with the affected members. CONCLUSIONS: This study adds another evidence that DYT1 phenotype can present with purely focal and task-specific dystonia in all the affected members of a family. Marked and sustained improvement following thalamotomy in three of our patients suggests that stereotaxic thalamotomy is beneficial in familial focal dystonia with DYT1 mutation. (J Korean Neurol Assoc 19(2):110~115, 2001)

Familial Writer's Cramp with DYT1 Mutation: A Clinical and Genetic Analysis of a New Kindred

BACKGROUND: Recently a non-Jewish German family with writer's cramp was reported to have DYT1 mutation, expanding the phenotypic spectrum of DYT1. Although functional brain surgery has been tried for generalized dystonia, surgical outcome in focal dystonia patients with DYT1 mutation has not yet been reported. We investigated the clinical features and response to thalamotomy in familial writer's cramp with DYT1 mutation. METHODS: Family members were examined and clinically affected cases were video-taped. For the detection of DYT1 mutation, PCR-RFLP(restriction fragment length polymorphism) and heteroduplex analyses were performed as screening tests. Additional DNA sequencing was performed for the proband case to confirm the GAG deletion. RESULTS: Among this clinically homogeneous non-Jewish Korean family, five members in three generations were affected. Age of onset ranged from 7 to 20 years. Writing difficulty was the initial and the main disabling problem for all the affected individuals. All had the bilateral writer's cramp in succession. Dystonia remained focal and task-specific for the entire period after onset. Unilateral thalamotomy was performed in three patients, with remarkable improvement. Surgical benefit remained unchanged during the follow-up period of 6-8 years. DYT1 mutation cosegregated with the affected members. CONCLUSIONS: This study adds another evidence that DYT1 phenotype can present with purely focal and task-specific dystonia in all the affected members of a family. Marked and sustained improvement following thalamotomy in three of our patients suggests that stereotaxic thalamotomy is beneficial in familial focal dystonia with DYT1 mutation. (J Korean Neurol Assoc 19(2):110~115, 2001)

Simultaneous Ipsilateral Posteroventral Pallidotomy and Ventrolateral Thalamotomy for Advanced Parkinson's Disease

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.

Treatment of Parkinson's Disease by Streotactic Thalamotomy and Pallidotomy

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(p0.557). 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.

MRI-guided Stereotactic Thalamotomy for Cerebral Palsy Patients of Mixed Dyskinesia

A few neurosurgical alleviate to alleviate some dyskinesias of cerebral palsy(CP) have been tried. For the spastic and tremor type, the selective posterior rhizotomy and thalamotomy are regarded as treatments of choice but other dyskinesias remains a tough challenge. The authors have performed 48 cases of MRI-guided stereotactic thalamotomy(MGST) in 37 CP patients with mixed dyskinesias from Jun. '92 to Jan. '95 using CRW stereotactic frame and MRI, without any ventriculogram. Depending upon the types of main dyskinesias, the target including ventrolateral nucleus of thalamus or medial nucleus of globus pallidus was(were) selected. Clinical results were verified in terms of preoperative symptoms improvement and patient's satisfaction. In athetoid(42 MGSTs in 32CPs) : excellent 6, good 26, fair 10, and in dystonia(30 MGSTs in 23 CPs): excellent 2, good 18, fair 10, and in spasticity(20 in 17 CPs): excellent 3, good 12, fair 5, and in choreoor choreoathetoid(7 in 6 CPs) : good 5, fair 2. Recurrence of symptoms after operation was noted in 6 cases(12.5%). Postoperative morbidity including motor weakness, speech disturbance, swallowing difficulty, and sensory abnormality were transiently noted in 9 cases(18.8%). It is the authors observation that MGST seems to be one of the beneficial procedures for relieving symptoms of CP with mixed dyskinesias.

Clinical Analysis of Stereotactic Thalamotomy for Medically Intractable Essential Tremor

Stereotactic ventrolateral thalamotomy has been successful in treating a wide spectrum of involuntary movement disorders. But very little has been reported concerning their application in essential tremor. Twenty three patients with medically refractory disabling essential tremor underwent ventralis(VL) thalamotomies. The procedure was unilateral in twenty three cases. Contralateral tremor remained abscent or markedly reduced in 22 patients at the time of the most recent follow-up examinations at a mean of 2.9 months after surgery. Disability was determined by a modified form of an estabilished rating scale for termor reported by Fahn and was reduced from a mean score of 11 to 3(p<0.0001) after the operation. Persistent surgical morbidity was limited to three patients with mild dysarthria and two with a mild cognitive impairment. There were no surgically related deaths. It is concluded that stereotactic VL thalamotomy is a treatment option for medically intractable disabling essential tremor.

Basic Estimation of Intracerebral Reference Points: Data Analysis from 169 Korean People

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.

Analysis of the related factors on staged bilateral multi-targets pallidotomy and thalamotomy for treatment of Parkinson's disease / 临床神经病学杂志

Objective To explore the related factors for improving the effect of the staged bilateral multi-targets pallidotomy and thalamotomy on Parkinson's disease.Methods 387 patients were divided into different groups according to various factors,including the age of patient,operation method,interval of radiofrequency and the diameter of electrode. The relationship between the above mentioned factors and the effect or complication was analyzed.Results All the symptoms of PD were significantly improved after second operation in the near future. Staged bilateral pallidotomy was the most popular operation way in clinical practicing. The incidence of complication of staged bilateral thalamotomy was high (100%). The rate of complication in the patients over 55 years old (29.70%) was higher than that in the patients not more than 55 years old (12.66%)( P

Stereotaxic Thalamotomy in the Management of Parkinson's Disease

A retrospective analysis was done on twenty-nine patients with Parkinson's disease who underwent thirty-five stereotaxic thalamotomies during the past 21 years. Eighteen patients received unilateral surgery, and six received two-staged bilateral surgery. Five had second stage operation after contralateral operation at other hospitals. Thirteen patients were followed-up for a period of six months to 12 years but the remainder were lost to follow-up. Parkinsonism scoring scale was designed and used to investigate postsurgical results and progress of patients. Clinical symptoms improved in 94.7% immediately after surgery. Only one patient had permanent neurological deficit resulting from the operation. A long-term follow-up study, with statistical analysis, suggested that progressive worsening after surgery was not ue to recurrence of tremor and rigidity but aggravation of bradykinesia and axial symptoms in the natural course of the disease. After unilateral surgery, 53.3% of patients had progressive aggravation of symptoms in contralateral side. It is believed that surgical treatment should be considered in patients presenting symptoms of tremor and rigidity. Bilateral surgery is indicated in patients who have bilateral symptoms or contralateral aggravation of symptoms after an initial operation.

Influence of Individual Symptomatology on the Surgical Results of Parkinson's Disease

Changes in the individual symptomatology were analyzed on twenty-nine patients with Parkinson's disease who underwent thirty-five stereotaxic thalamotomies to evaluate the influence of each symptom on the surgical results. The thalamotomy could obviously improve and prevent progression of tremor and rigidity but not bradykinesia and axial symptoms. Long-term follow-up wtudy with statistical analysis suggested that progressive worsening after surgery was due not to recurrence of tremor and rigidity but aggravation of bradykinesia and axial symptoms in the natural course of the disease. We believe that timely surgical treatment should be encouraged in patients presenting symptoms of tremor and rigidity.