Asymptomatic cable twisting in a patient with impending Twiddler syndrome detected during deep brain stimulation surgery for Parkinson's disease: A case report.

Background: Deep brain stimulation (DBS) has consistently demonstrated high efficacy and safety in patients with Parkinson's disease. Twiddler's syndrome is a rare occurrence of hardware failure in patients undergoing neuromodulation. We report here a case of subclinical cable twisting jeopardizing Twiddler's syndrome in a patient with Parkinson's disease who underwent DBS surgery targeting the globus pallidus internus (GPI). Case Description: A 70-year-old woman with a 7-year history of Parkinson's disease refractory to medication was referred to our department for treatment of involuntary movements of the left hand and leg. She underwent right GPI DBS implantation. Left GPI DBS implantation was subsequently planned to manage resting tremors that developed in the right leg after the first surgery at around one year after the first surgery. During a routine check-up before the second surgery, we incidentally detected Twiddler's syndrome. The patient showed no neurological deficits in the left extremities, the same as before right GPI DBS. We performed left GPI DBS concomitantly with the revision of the implantable pulse generator and extension wire. Conclusion: Twiddler's syndrome is a rare complication of DBS. Subclinical risk of cable twisting jeopardizing Twiddler's syndrome is rarely detected without clinical indications of hardware failure. Neurosurgeons should be cognizant of and regularly monitor the implanted device in case serious complications occur.

Proceedings of the 11th Annual Deep Brain Stimulation Think Tank: pushing the forefront of neuromodulation with functional network mapping, biomarkers for adaptive DBS, bioethical dilemmas, AI-guided neuromodulation, and translational advancements.

The Deep Brain Stimulation (DBS) Think Tank XI was held on August 9-11, 2023 in Gainesville, Florida with the theme of "Pushing the Forefront of Neuromodulation". The keynote speaker was Dr. Nico Dosenbach from Washington University in St. Louis, Missouri. He presented his research recently published in Nature inn a collaboration with Dr. Evan Gordon to identify and characterize the somato-cognitive action network (SCAN), which has redefined the motor homunculus and has led to new hypotheses about the integrative networks underpinning therapeutic DBS. The DBS Think Tank was founded in 2012 and provides an open platform where clinicians, engineers, and researchers (from industry and academia) can freely discuss current and emerging DBS technologies, as well as logistical and ethical issues facing the field. The group estimated that globally more than 263,000 DBS devices have been implanted for neurological and neuropsychiatric disorders. This year's meeting was focused on advances in the following areas: cutting-edge translational neuromodulation, cutting-edge physiology, advances in neuromodulation from Europe and Asia, neuroethical dilemmas, artificial intelligence and computational modeling, time scales in DBS for mood disorders, and advances in future neuromodulation devices.

Microlesion Effect Induced by Electrode Implantation in the Posteroventral Globus Pallidus Interna for Severe Dystonic Tics.

Background: Tourette syndrome (TS) is a neurologic condition characterized by motor and phonic tics. Dystonic tics, including blepharospasm, are considered atypical or unusual in severe TS. Case Report: We report a severe case of TS with facial dystonic tics resembling blepharospasm in which the microlesion effect and a sustained therapeutic effect was observed with bilateral globus pallidus interna (GPi) deep brain stimulation (DBS). Discussion: Bilateral GPi DBS can be beneficial for blepharospasm-like tics and severe symptoms of TS. The improvements seen can be explained by the microlesion effect induced by DBS lead placement in the GPi.

Presence of intra-aneurysmal thrombi with delayed coil migration after embolization of an aneurysmal subarachnoid hemorrhage: illustrative case.

BACKGROUND: Coil migration is a rare, but notable complication of endovascular treatment. Risk factors include communicating segment aneurysms, aneurysmal shape, and technical factors. Although cerebral blood flow obstruction caused by early coil migration requires urgent coil removal, delayed coil migration is often asymptomatic, making it difficult to determine a treatment strategy. OBSERVATIONS: A 47-year-old woman was referred to the institute with acute-onset headache. She was diagnosed with subarachnoid hemorrhage due to rupture of the right internal carotid artery-posterior communicating artery aneurysm and underwent endovascular coil embolization. Following the procedure, the patient showed no obvious complications; however, 14 days later, images showed coil migration to the distal side, leading to surgical removal. Right frontotemporal craniotomy was performed, and the remaining coil was removed. The aneurysm was clipped again, and blood flow was confirmed. The patient was discharged 12 days after the craniotomy with transient oculomotor nerve palsy. At the 15-month follow-up, there was no aneurysm recurrence and the oculomotor nerve palsy showed improvement. LESSONS: Retrieval of the migrated coil by craniotomy is an effective remedial measure; however, intraoperative complications are common. Early detection, established protocols, and prompt treatment decisions are important for preventing undesirable outcomes.

Repeated coil embolization of traumatic basilar artery pseudoaneurysm accompanied by bilateral traumatic internal carotid artery stenosis following severe head injury in a pediatric patient: A case report and literature review.

Background: Few cases of pediatric traumatic intracranial aneurysms (pTICAs) in the posterior circulation involving the basilar artery (BA) following severe head trauma have been reported. Here, we describe a pediatric case of traumatic BA pseudoaneurysm accompanied by bilateral traumatic internal carotid artery (ICA) stenosis following blunt head trauma. Case Description: A 16-year-old boy presented to our emergency department after being hit by a car. The patient was initially diagnosed with multiple skull base fractures underlying traumatic subarachnoid hemorrhage and left acute epidural hematoma. Seven days following emergency craniectomy, magnetic resonance imaging revealed bilateral ICA stenosis, BA stenosis, and BA pseudoaneurysm. We decided to perform coil embolization, resulting in body filling and a volume embolization ratio of 15.7%. Twenty-eight days after coil embolization, digital subtraction angiography revealed aneurysmal rupture. We performed repeated coil embolization, resulting in body filling and a volume embolization ratio of 20.9%. Conclusion: We reported a pediatric case of traumatic BA pseudoaneurysm accompanied by bilateral traumatic ICA stenosis following a severe head injury treated with repeated coil embolization. Considering the risk of further brain injury due to high incidence of rupture, early vascular survey and appropriate treatment may be the most important prognostic factors in pTICAs.

Disappearance of a moyamoya-related distal anterior cerebral artery aneurysm after target bypass revascularization: illustrative case.

BACKGROUND: Aneurysm formation is a complication of moyamoya disease (MMD). Distal anterior cerebral artery (ACA) aneurysms account for approximately 1% of MMD-related aneurysms. We report a case of target bypass for adult patients with MMD who presented with intracranial hemorrhage due to rupture of a distal ACA aneurysm, whose disappearance was confirmed postoperatively. OBSERVATIONS: A 45-year-old woman presented with sudden-onset headache and loss of consciousness. Head computed tomography showed hemorrhage in the genu of the corpus callosum with intraventricular extension. Digital subtraction angiography (DSA) revealed Suzuki stage III MMD and a left A3 segment aneurysm. Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass and STA-ACA target bypass were performed to reduce hemodynamic stress on the left ACA. DSA 6 months after surgery showed patency of both bypasses and disappearance of the aneurysm. At the 20-month follow-up, the patient was asymptomatic and neurologically intact. LESSONS: Bypass revascularization may be an effective treatment to reduce hemodynamic stress and eliminate MMD-related aneurysms.

Precision Mapping of Thalamic Deep Brain Stimulation Lead Positions Associated With the Microlesion Effect in Tourette Syndrome.

BACKGROUND: The microlesion effect refers to the improvement of clinical symptoms after deep brain stimulation (DBS) lead placement and is suggested to indicate optimal lead placement. Very few studies have reported its implications in neuropsychiatric disorders. OBJECTIVE: To evaluate the magnitude of the microlesion effect in Tourette syndrome and the relationship between the microlesion effect and the anatomic location of implanted DBS leads. METHODS: Six male patients were included. Their median age at surgery and follow-up period were 25 years (range, 18-47) and 12 months (range, 6-24), respectively. All patients were videotaped pre- and postoperatively, and tic frequencies were counted. We also analyzed the precision of lead placement and evaluated the normative connectome associated with the microlesion area. RESULTS: The microlesion effect was observed as an improvement in tic symptoms in all patients, and the long-term clinical outcomes were favorable. The median motor tic frequency was 20.2 tics/min (range, 9.7-60) at baseline and decreased to 3.2 tics/min (1.2-11.3) in patients on postoperative day 1 ( P = .043) and to 5.7 tics/min (range, 1.9-16.6) in patients on postoperative day 7 ( P = .028). Phonic tic tended to improve immediately after surgery although the changes were not significant. Image analyses revealed that the precise position of the electrode was directed toward the anteromedial centromedian nucleus. Normative connectome analysis demonstrated connections between improvement-related areas and wide areas of the prefrontal cortex. CONCLUSION: This study shows that the microlesion effect may seem as an immediate improvement after optimal DBS lead placement in patients with Tourette syndrome.

Case report: isolated trochlear nerve palsy associated with posterior cerebral artery aneurysm.

We describe a case of isolated trochlear nerve palsy caused by an unruptured posterior cerebral artery (PCA) aneurysm in an 82-year-old male who consulted an ophthalmologist after developing diplopia. Magnetic resonance angiography showed a left PCA aneurysm in the ambient cistern, and T2WI showed an aneurysm compressing the left trochlear nerve to the cerebellar tentorium. Digital subtraction angiography revealed that the lesion was located between the left P2a segment. We attributed this isolated trochlear palsy to left PCA unruptured aneurysm pressure. Thus, we performed stent-assisted coil embolization. The aneurysm was obliterated, and trochlear nerve palsy improved completely.

Manual superficial temporal artery compression using a circular plastic material for embolization of meningioma: illustrative case.

BACKGROUND: In meningiomas that occur in the high-convexity region, the superficial temporal artery (STA) frequently feeds the tumor, and when embolizing from the middle meningeal artery (MMA), the embolic material may not reach the tumor vessels because of the pressure gradient resulting from the STA blood flow, resulting in inadequate embolization. In this case, a circular plastic material was used to apply circumferential pressure around the parietal foramen to control blood flow to the tumor. OBSERVATIONS: A 45-year-old male underwent head magnetic resonance imaging that revealed a 2.2-cm meningioma in the right high-convexity region. Preoperative embolization was performed. When N-butyl-2-cyanoacrylate was injected from the right MMA while using a circular plastic material to compress the skin around the parietal foramen through which the bilateral STAs (the tumor feeders) flow, it was able to fully penetrate the tumor vessel and occlude the other feeders in a retrograde manner. The patient underwent tumor removal after embolization uneventfully. LESSONS: Manual compression of the STA using a circular plastic material is useful when the tumor is fed by the STA through the parietal foramen and is also applicable to transarterial embolization of dural arteriovenous fistulas fed by the STA or occipital artery.

Case report: Radiofrequency thalamotomy as palliative care for Holmes tremor in a patient with terminal cancer and cardiac pacemaker.

Background: Herein, we present a case report of a patient with Holmes tremor due to thalamic infarction with end-stage pancreatic cancer who underwent successful computed tomography (CT)-guided ventralis intermedius nucleus (Vim) thalamotomy as palliative care. Case Description: A 78-year-old man with gradually worsening involuntary movements on the left side of his body 2 years after a right thalamic infarction was referred to our institute. He had a history of chronic atrial fibrillation for which he was implanted with a cardiac pacemaker not compatible with magnetic resonance imaging. He also received adjuvant therapy for pancreatic cancer. As the involuntary movements interfered with his daily life, the patient elected for neurosurgical treatment despite having terminal cancer. Although the prognosis for pancreatic cancer was considered to be more than 6 months at the time of surgery, we performed CT-guided Vim thalamotomy under local anesthesia without pulse generator implantation considering the patient's general condition. The involuntary movements of the left side of the body reduced following surgery, thus improving his quality of life (QOL). However, 6 months after thalamotomy, the patient died of pancreatic cancer. Conclusion: Thalamotomy significantly reduced the involuntary movements immediately after the procedure. Therefore, thalamotomy can be performed under local anesthesia without the use of any device and may contribute to the improvement of QOL in terminal patients.

Pain Relief Following Selective Tibial Neurotomy for Spastic Equinus Foot Secondary to Stroke and Traumatic Brain Injury.

OBJECTIVE: Selective tibial neurotomy (STN) has been indicated for spastic equinus foot (SEF); however, the impact of this procedure on quality of life and activities of daily living has not been evaluated in detail. This study aimed to evaluate the surgical outcomes of STN and its effect on SEF accompanied by pain. METHODS: We evaluated 26 patients (mean age: 59.6 ± 15.2 years; 14 men and 12 women) who underwent STN for SEF, 10 of whom complained of spontaneous pain preoperatively. We used the following scales for clinical evaluation: the Modified Ashworth Scale, Medical Research Council (MRC), 10-m walking test, Functional Independence Measure, and numeric rating scale for pain. These scales were evaluated preoperatively and postoperatively. Differences in clinical characteristics were compared between the 10 patients with pain and the 16 patients without pain. RESULTS: Significant differences were observed in all evaluation scale scores except for the Functional Independence Measure, and no serious adverse events were reported. Pain intensity was significantly improved from 6.4 ± 2.0 to 2.7 ± 2.3 (P < 0.05). An analysis showed that the preoperative mean Medical Research Council score of ankle movement was significantly lower in patients with pain but recovered to the same level postoperatively at the 6-month follow-up. CONCLUSIONS: Our study showed significant improvements in spasticity and its associated symptoms, and STN effectively addressed spastic pain and motor weakness. Among various treatment modalities, STN may be positively indicated for patients with spastic pain in the lower leg.

Unilateral GPi-DBS Improves Ipsilateral and Axial Motor Symptoms in Parkinson's Disease as Evidenced by a Brain Perfusion Single Photon Emission Computed Tomography Study.

Introduction: Deep brain stimulation (DBS) is an effective treatment for advanced Parkinson's disease (PD) with the targeting bilateral subthalamic nucleus or globus pallidus internus (STN or GPi-DBS). So far, detailed studies on the efficacy of unilateral STN-DBS for motor symptoms have been reported, but few studies have been conducted on unilateral GPi-DBS. Materials and Methods: Seventeen patients with Parkinson's disease (PwPD) who underwent unilateral GPi-DBS were selected. We conducted comparison analyses between scores obtained 6-42 months pre- and postoperatively using the following measurement tools: the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part III, the Hoehn and Yahr stage, the presence/absence of dyskinesia, Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB), Geriatric Depression Scale (GDS), levodopa equivalent dose (LED), and cerebral blood flow by single photon emission computed tomography (SPECT). Patient backgrounds were compared between four cohorts with favorable (good responders, ≥50% improvement) and unfavorable (poor responders, <50% improvement) postoperative outcome. Results: Significant improvement was observed postoperatively in the following: total MDS-UPDRS Part III scores during the off period, contralateral scores, ipsilateral scores, and axial scores. Similarly, the Hoehn and Yahr stages during the off period, and GDS also showed significant decrease. In contrast, LED, MMSE, and FAB remained unchanged while the number of patients who scored positive for dyskinesia decreased by 40%. Abnormal cerebral blood flow preoperatively seen in the cerebral cortex had normalized in the total score-based good responder cohort. In the ipsilateral score-based good responder cohort, cerebral blood flow increased in the contralateral frontal lobe including in the premotor cortex, contralateral to the DBS. Compared to the poor responders, postoperative good responders demonstrated significantly higher preoperative MMSE scores. Discussion: Unilateral GPi-DBS therapy was effective in improving contralateral, ipsilateral, and axial motor symptoms of patients with advanced PD; in particular, it was found to be especially beneficial in PwPD whose cognitive function was unimpaired; the treatment efficacy rivaled that of bilateral counterparts up till at least 6 months postoperatively. Finally, normalization of preoperative abnormalities in cerebral blood flow and increased cerebral blood flow in the contralateral frontal lobe indicated the beneficial potential of this therapy on ipsilateral motor symptoms.

Favorable management of symptomatic cerebellar hemangioblastoma presenting with obstructive hydrocephalus during pregnancy: A case report and literature review.

Background: Cerebellar hemangioblastoma is a highly vascular benign tumor and the growth rate of hemangioblastomas is believed to often accelerate during pregnancy; however, the reason for this rapid increase in size remains poorly understood. There are several case reports of symptomatic hemangioblastoma during pregnancy; however, the favorable management strategy has not been well established. Case Description: A 35-year-old woman, gravida 2 para 1, with no significant medical history presented with vertigo and difficulty walking at around 11 weeks of pregnancy and was referred to our institute at 30 weeks of gestation because of worsening symptoms. Brain magnetic resonance imaging revealed a 5.6 cm cystic lesion with a mural nodule in the right cerebellar hemisphere and the lesion blocked cerebrospinal fluid drainage from the fourth ventricle and brainstem, resulting in obstructive hydrocephalus. After obtaining the patient's consent, a multidisciplinary team consisting of obstetricians and neurosurgeons decided to perform resection of the intracranial lesion following delivery of the fetus by emergency cesarean section in view of the symptoms of increased intracranial pressure. The patient's general condition was confirmed to be stable postoperatively and she was discharged on the 16th day of her hospitalization without any neurological deficits or fetal complications. Conclusion: Urgent tumor resection combined with cesarean section can be planned once fetal lung maturity is confirmed. Most cases of symptomatic hemangioblastoma during pregnancy have an uneventful gestational course and a favorable outcome for both mother and child.

Effect of Robot-assisted Rehabilitation to Botulinum Toxin A Injection for Upper Limb Disability in Patients with Chronic Stroke: A Case Series and Systematic Review.

Combining single-joint hybrid assistive limb (HAL-SJ) with botulinum toxin A (BTX-A) therapy is novel and has great therapeutic potential for the rehabilitation of stroke patients with upper limb paralysis. The purpose of this observational case series study was to evaluate the effect of BTX-A and HAL-SJ combination therapy on different exoskeleton robots used for treating upper limb paralysis. The HAL-SJ combination received a BTX-A injection followed by HAL-SJ-assisted rehabilitation for 60 min per session, 10 times per week, during 2 weeks of hospitalization. Clinical evaluations to assess motor function, limb functions used during daily activities, and spasticity were performed prior to injection, at 2-week post-treatment intervention, and at the 4-month follow-up visit. The total Fugl-Meyer assessment-upper limb (FMA-UE), proximal FMA-UE, action research arm test (ARAT), Motor Activity Log (MAL), and Disability Assessment Scale (DAS) showed a statistically significant difference, and a large effect size. However, the FMA distal assessment at 2-week post-treatment intervention showed no significant difference and a moderate effect size. The FMA-UE scores of the extracted systematic review articles showed that our design improved upper limb function. The change in the total FMA-UE score in this study showed that, compared to previous reports in the exoskeletal robotic therapy group, our combination therapy had a higher score than five of the seven references. Our results suggest that BTX-A therapy and HAL-SJ combination therapy may improve upper limb function, similar to other treatment methods in the literature.

Functional Prognosis Following Temporal Bone Chondroblastoma Resection: A Systematic Review and Case Illustration.

BACKGROUND: Chondroblastomas are rare tumors that account for <1% of all bone tumors, and 5.7% of them occur in the skull. The aim of this study was to investigate factors related to their functional prognosis by conducting a systematic review, including our own case. METHODS: A systematic review was conducted of case reports that clearly stated postoperative symptoms in temporal chondroblastomas. Tumor localization was limited to cases of the temporal bone. Cases not described in English were excluded. RESULTS: We obtained 30 articles comprising 44 cases and included our own case for a total of 45 cases. Postoperative asymptomatic cases accounted for 53.3% (24/45), and symptomatic cases accounted for 46.7% (21/45). Complications were observed in 31.1% (14/45) of cases. The main complications were facial palsy (9 cases), occlusal disorders (4 cases), and hearing loss (4 cases). The occurrence of facial palsy as a complication was considered likely. Tumor size was confirmed in 36 cases. Cases with postoperative complications were more likely to involve tumors ≥5 cm in size (77.8%, 7/9) compared with cases without complications (40.7%, 11/27). There was a significant association between rate of postoperative complications and tumor size (P = 0.061). CONCLUSIONS: As temporal chondroblastoma poses a risk of residual postoperative symptoms when the tumor grows, aggressive surgical treatment should be considered even in asymptomatic or small tumors.

Enlargement of preexisting superficial temporal artery pseudo-aneurysm co-incidental to mask wearing during the Covid-19 pandemic.

The superficial temporal artery (STA) pseudo-aneurysm is usually associated with trauma. We report a unique case of an STA pseudo-aneurysm that developed due to mask wearing during the Covid-19 pandemic. A 70-year-old female presented with a 3-month history of a rapidly growing pseudo-aneurysm of the right STA. Over the past 3 months the patient had been wearing a mask for the prevention of Covid-19. The STA aneurysm was located exactly at a pressure point created by the rubber mask. Therefore, we assumed that an enlargement of the preexisting aneurysm had taken pace due to irritation from the elastic band of the mask. Surgical excision of the aneurysm and reconstruction of the STA using STA-STA bypass were performed. To our knowledge, we here report the first case of an STA pseudo-aneurysm that was potentially affected indirectly by the Covid-19 pandemic. Clinicians should be cautious about the preexisting medical condition that is potentially worsened by mask band compression.

Neuroanatomical considerations for optimizing thalamic deep brain stimulation in Tourette syndrome.

OBJECTIVE: Deep brain stimulation (DBS) of the centromedian thalamic nucleus has been reportedly used to treat severe Tourette syndrome, yielding promising outcomes. However, it remains unclear how DBS electrode position and stimulation parameters modulate the specific area and related networks. The authors aimed to evaluate the relationships between the anatomical location of stimulation fields and clinical responses, including therapeutic and side effects. METHODS: The authors collected data from 8 patients with Tourette syndrome who were treated with DBS. The authors selected the active contact following threshold tests of acute side effects and gradually increased the stimulation intensity within the therapeutic window such that acute and chronic side effects could be avoided at each programming session. The patients were carefully interviewed, and stimulation-induced side effects were recorded. Clinical outcomes were evaluated using the Yale Global Tic Severity Scale, the Yale-Brown Obsessive-Compulsive Scale, and the Hamilton Depression Rating Scale. The DBS lead location was evaluated in the normalized brain space by using a 3D atlas. The volume of tissue activated was determined, and the associated normative connective analyses were performed to link the stimulation field with the therapeutic and side effects. RESULTS: The mean follow-up period was 10.9 ± 3.9 months. All clinical scales showed significant improvement. Whereas the volume of tissue activated associated with therapeutic effects covers the centromedian and ventrolateral nuclei and showed an association with motor networks, those associated with paresthesia and dizziness were associated with stimulation of the ventralis caudalis and red nucleus, respectively. Depressed mood was associated with the spread of stimulation current to the mediodorsal nucleus and showed an association with limbic networks. CONCLUSIONS: This study addresses the importance of accurate implantation of DBS electrodes for obtaining standardized clinical outcomes and suggests that meticulous programming with careful monitoring of clinical symptoms may improve outcomes.

Personalized Medicine in Parkinson's Disease: New Options for Advanced Treatments.

Parkinson's disease (PD) presents varying motor and non-motor features in each patient owing to their different backgrounds, such as age, gender, genetics, and environmental factors. Furthermore, in the advanced stages, troublesome symptoms vary between patients due to motor and non-motor complications. The treatment of PD has made great progress over recent decades and has directly contributed to an improvement in patients' quality of life, especially through the progression of advanced treatment. Deep brain stimulation, radiofrequency, MR-guided focused ultrasound, gamma knife, levodopa-carbidopa intestinal gel, and apomorphine are now used in the clinical setting for this disease. With multiple treatment options currently available for all stages of PD, we here discuss the most recent options for advanced treatment, including cell therapy in advanced PD, from the perspective of personalized medicine.

[Surgical Technique of Ventral Intermediate Thalamic Deep Brain Stimulation].

Deep brain stimulation(DBS)of ventral intermediate(Vim)thalamic nucleus is an established procedure for tremor disorders, however, there are technical variations among specialists. The most common indications of Vim DBS are essential tremor(ET)and tremor dominant Parkinson's disease(PD), and less commonly other tremor disorders including Holmes tremor are treated with the same procedure. The variations of the surgical technique exist in the preoperative imagings and planning of the DBS electrode trajectory. In this review, we explain about the basic concept of Vim DBS and our surgical method.