Long-term follow-up of task-specific tremor after thalamotomy: a retrospective observational study.

OBJECTIVE: This study aimed to report the long-term results of thalamotomy in 23 patients with task-specific tremor. METHODS: Data of 23 patients with task-specific tremor who underwent ventralis intermedius nucleus and posterior part of ventro-oral nucleus thalamotomy at the Tokyo Women's Medical University Hospital between 2010 and 2022 were retrospectively analyzed. To evaluate neurological conditions, the severity of task-specific tremor was divided into 0 (no tremor), 1 (slightly tremulous), 2 (moderately tremulous), 3 (accomplishing tasks with great difficulty), and 4 (unable to complete tasks). We also used the subscores "handwriting" (0-4) and "spiral drawing" (0-4) of the Clinical Rating Scales for Tremor. Evaluation scales were presented as medians and interquartile ranges. RESULTS: The severities of task-specific tremor were 3.0 (3.0-4.0) preoperatively and 0.0 (0.0-0.0, p < 0.0001) at the last available evaluation. The writing and spiral drawing of the Clinical Rating Scales for Tremor significantly improved from 3.0 (3.0-4.0) and 3.0 (2.0-3.0) preoperatively, respectively, to 0.0 (0.0-0.0, p < 0.0001) and 0.0 (0.0-0.0, p < 0.0001) at the last available evaluation, respectively. The mean clinical follow-up period was 62.7 ± 26.0 months. Seven (30.4%) patients had focal hand dystonia, which newly developed on the ipsilateral side of the tremor at 2-45 months after the surgery. No serious complications were observed. INTERPRETATION: Thalamotomy significantly improves task-specific tremor with high long-term efficacy, and long-term follow-up is important because focal hand dystonia can develop postoperatively.

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.

An Experience With an Exoscope System (ORBEYE) for Surgery for Tarsal Tunnel Syndrome: A Case Report.

Surgery for peripheral entrapment neuropathy aims to decompress the affected nerve and optimize the visualization of anatomical details during surgery. This paper describes our experience using the ORBEYE exoscope (Olympus) during surgery for tarsal tunnel syndrome (TTS). The patient was a 70-year-old male with complaints of bilateral pain and numbness on the plantar surface of the bilateral soles and medial halves of both lower limbs. He was diagnosed with idiopathic TTS with the American Orthopedic Foot and Ankle Score (AOFAS) of 20/100. Surgery for the right foot was performed under local anesthesia with the patient's body in the lateral position. All procedures were performed using the ORBEYE exoscope view. The posterior tibial artery (PTA) was transposed, and the flexor retinaculum was reconstructed between the PTA and posterior tibial nerve. Indocyanine green (ICG) video angiography confirmed the absence of PTA flow disturbance. One month after the first operation, left foot surgery was performed. Three months later, the AOFAS had improved from 20/100 to 50/100. The ORBEYE exoscope is useful in TTS treatment and represents a feasible and comfortable technique for entrapment neuropathy surgery. In addition, ICG capability is an effective tool for confirming blood flow in PTA after transposition.

[Development of Medical Materials and Infection].

Surgery has the possibility to cause infections. Surgical site infection(SSI)is a common complication of various surgical procedures. On the other hand, allogeneic tissue-derived material-induced infections, such as transfusion-related hepatitis and Creutzfeldt-Jakob disease, are rare but occur. The risk of surgery-related infections needs to be reduced because such infections not only affect morbidity and mortality but also lead to increased medical costs and longer hospitalization. Recently, various allogeneic and synthetic medical materials have been developed, and many types of materials have been used in daily neurosurgical procedures. Some synthetic materials have been advertised to have an SSI-preventive effect. Technology has also been developed to minimize the infectivity of allogeneic materials. In this paper, we introduce some information focused on the infectivity of fibrin glue and DuraGen® and the SSI-preventive effect of Surgicel® and antimicrobial sutures.

Intraparenchymal Symptomatic Cyst Formation Around the Deep Cerebellar Stimulation Electrode.

Intraparenchymal cyst formation around a deep brain stimulation electrode is a rare complication. This is the first report of intraparenchymal cyst formation along a deep cerebellar stimulation electrode in the posterior cranial fossa. The patient was a 27-year-old man with DYT-1 early-onset isolated dystonia who received bilateral deep cerebellar stimulation. He developed dizziness, nausea, and dysarthria 1 month following the deep cerebellar stimulation surgery. Head computed tomography revealed multiple cysts along the left electrode. The contrast medium of computed tomography did not enhance the appearance of the cystic lesions. We confirmed the absence of fever and sterile cerebrospinal fluid. Steroid therapy for 3 weeks was not radiologically and symptomatically useful. He underwent aspiration surgery. The cyst fluid was light yellow, sterile, and rich in protein. Despite substantial improvement in nausea and dysarthria within 1 week postoperatively, dizziness required 1 month to recover. Cystic formations gradually decreased with time.

Deep Brain Stimulation of the Forel's Field for Dystonia: Preliminary Results.

The field of Forel (FF) is a subthalamic area through which the pallidothalamic tracts originating from the globus pallidus internus (GPi) traverse. The FF was used as a stereotactic surgical target (ablation and stimulation) to treat cervical dystonia in the 1960s and 1970s. Although recent studies have reappraised the ablation and stimulation of the pallidothalamic tract at FF for Parkinson's disease, the efficacy of deep brain stimulation of FF (FF-DBS) for dystonia has not been well investigated. To confirm the efficacy and stimulation-induced adverse effects of FF-DBS, three consecutive patients with medically refractory dystonia who underwent FF-DBS were analyzed (tongue protrusion dystonia, cranio-cervico-axial dystonia, and hemidystonia). Compared to the Burke-Fahn-Marsden Dystonia Rating Scale-Movement Scale scores before surgery (23.3 ± 12.7), improvements were observed at 1 week (8.3 ± 5.9), 3 months (5.3 ± 5.9), and 6 months (4.7 ± 4.7, p = 0.0282) after surgery. Two patients had stimulation-induced complications, including bradykinesia and postural instability, all well controlled by stimulation adjustments.

Case Report: Deep Cerebellar Stimulation for Tremor and Dystonia.

Background: The cerebellum plays an important role in the pathogenesis and pathophysiology of movement disorders, including tremor and dystonia. To date, there have been few reports on deep cerebellar stimulation. Case Report: The patient was a 35-year-old previously healthy man with no history of movement disorders. He developed a tremor and stiffness in his left hand at the age of 27 years, which was diagnosed as a dystonic tremor. We performed right thalamotomy, which resulted in a complete resolution of the tremor; however, the dystonia persisted. Subsequently, the patient developed left foot dystonia with inversion and a newly developed tremor in the right hand and foot. The patient underwent left ventralis intermedius (VIM) deep brain stimulation (VIM-DBS) and left pallidothalamic tract DBS (PTT-DBS). Left VIM-DBS completely resolved the right hand and foot tremor, and PTT-DBS significantly improved the left hand and foot dystonia. Three months postoperatively, the patient developed an infection and wound disruption at the surgical site. We performed palliative surgery for deep cerebellar stimulation via the posterior cranial region, which was not infected. The surgery was performed under general anesthesia with the patient lying in the prone position. Eight contact DBS electrodes were used. The placement of electrodes extended from the superior cerebellar peduncle to the dentate nucleus. Both the right hand and foot tremor improved with right cerebellar stimulation. Further, both the left hand and foot dystonia improved with left cerebellar stimulation. Right and left cerebellar stimulation led to no improvement in the left hand and foot dystonia and right hand and foot tremor, respectively. Stimulation-induced complications observed in the patient included dizziness, dysphagia, and dysarthria. After the surgery, the patient developed hypersalivation and hyperhidrosis in the left side of the body, both of which did not improve with adjustments of stimulation parameters. At the 6-month follow-up, the tremor and dystonia had almost completely resolved. Conclusion: Deep cerebellar stimulation deserves consideration as a potential treatment for tremor and dystonia.

Comorbid seizure reduction after pallidothalamic tractotomy for movement disorders: Revival of Jinnai's Forel-H-tomy.

Forel-H-tomy for intractable epilepsy was introduced by Dennosuke Jinnai in the 1960s. Recently, Forel-H-tomy was renamed to "pallidothalamic tractotomy" and revived for the treatment of Parkinson's disease and dystonia. Two of our patients with movement disorders and comorbid epilepsy experienced significant seizure reduction after pallidothalamic tractotomy, demonstrating the efficacy of this method. The first was a 29-year-old woman who had temporal lobe epilepsy with focal impaired awareness seizure once every three months and an aura 10-20 times daily, even with four antiseizure medicines. For the treatment of hand dyskinesia, she underwent left pallidothalamic tractotomy and her right-hand dyskinesia significantly improved. Fourteen months later, she had experienced no focal impaired awareness seizure and the aura decreased to one to three times per month. The second case was that of a 15-year-old boy diagnosed with progressive myoclonic epilepsy, who developed generalized tonic-clonic seizure, which manifested once every month, despite treatment with five antiseizure medicines. After surgery, myoclonic movements in his right hand slightly improved. A one-year follow-up revealed that he had not experienced a generalized tonic-clonic seizure. The lesion locations in the two cases were close to the vicinity of Jinnai's Forel-H-tomy. Forel's field H deserves reconsideration as a treatment target for intractable epilepsy.

Lumbar Ganglioneuroma from the Paravertebral Body Presenting in Continuity Between Intradural and Extradural Spaces.

BACKGROUND: Ganglioneuroma is a well-differentiated benign tumor that develops from the ganglion cells of the posterior mediastinum, retroperitoneum, cervical spine, and adrenal glands. The paravertebral body, in which the sympathetic trunk exists, is a common tumor site, and tumor sometimes invades the spinal canal through the intervertebral foramen. There have been no reports regarding tumors with intradural and extradural continuity. We report a paravertebral ganglioneuroma extending between the intradural and extradural spaces and its surgical treatment. CASE DESCRIPTION: A 33-year-old man was admitted to the hospital with progressive left lower limb numbness. A dumbbell-type tumor progressing to the spinal canal via the left intervertebral foramen from the paravertebral body at L1-2 was detected, and intradural calcified lesions were found. Pathologic examination of a computed tomography-guided biopsy sample revealed a ganglioglioma. The extradural tumor was removed; however, the left lower limb pain gradually worsened. As complete block was observed on myelography, the intradural tumor was removed 8 months later. Intraoperative findings revealed that the intradural and extradural tumors were continuous through the L1 nerve root. CONCLUSIONS: This is the first known reported case of paravertebral ganglioneuroma presenting in continuity between the intradural and extradural spaces.

[Bilateral Pallidotomy for Tardive Dystonia:A Case Report].

Tardive dystonia is a movement disorder related to the use of dopamine-receptor-blocking drugs. Several reports have shown that deep brain stimulation of the globus pallidus internus(GPi-DBS)is effective in treating tardive dystonia. However, a few reports demonstrated the efficacy of ablation of the GPi(pallidotomy). We herein report a case of tardive dystonia successfully treated with bilateral pallidotomy. A 32-year-old man developed severe tardive dystonia 10 years after the chronic use of antipsychotic drugs. Withdrawal of the drugs and botulinum toxin injections were ineffective. The patient underwent bilateral pallidotomy for tardive dystonia because of rejection of the implanted DBS devices. Significant improvement was observed, with a 95% decrease in the Burke-Fahn-Marsden Dystonia Rating Scale(BFMDRS)movement score, and no severe adverse events occurred. Symptomatic relief persisted for nine months. Pallidotomy is a feasible and efficacious procedure for tardive dystonia treatment without the use of hardware implantations.