Unilateral Stereotactic Radiofrequency Lesioning as a Surgical Treatment Option for Meige Syndrome.

Background Meige syndrome is a segmental dystonia affecting the head and neck, with bilateral blepharospasm as the primary symptom. First-line treatment typically involves Botox injections. For cases resistant to this treatment, bilateral deep brain stimulation of the globus pallidus internus (GPi) is considered. This study explores the efficacy of unilateral radiofrequency (RF) lesioning as an alternative surgical treatment for Meige syndrome. Methods We investigated six cases of medically refractory Meige syndrome treated with unilateral RF lesioning between October 2022 and August 2023. The procedures utilized the Leksell Stereotactic System (Elekta, Stockholm, Sweden) and the StealthStation S8 system (Medtronic, Dublin, Ireland). Target coordinates were initially set at 8-9 mm lateral and 1-2 mm inferior to the mid-commissure point (MCP) for the pallidothalamic tract (PTT), and 20 mm lateral, 2 mm anterior, and 3.0-4.5 mm inferior to the MCP for GPi, with fine adjustments based on MRI findings. Results The mean age of patients was 53. 3 ±16.5 years. Five patients underwent PTT RF lesioning, while one received GPi RF lesioning (pallidotomy). No surgical complications were reported. The Burke-Fahn-Marsden Dystonia Rating Scale scores were 32.9 ± 19.4 preoperatively and 17.7 ± 13.9 three months postoperatively, reflecting an average improvement of 42.7%. The Jankovic Rating Scale scores were 7.17 ± 0.76 preoperatively, 2.33 ± 2.34 the day after surgery (average improvement of 67%), and 3.50 ± 1.64 three months postoperatively (average improvement of 51%). Bilateral facial symptoms improved in four patients (67%). Conclusion Unilateral RF lesioning for Meige syndrome demonstrated the potential to improve bilateral symptoms and may be considered a viable treatment option for patients with refractory cases.

Status of functional neurosurgery in lower middle-income countries (LMICs): A multinational cross sectional survey based analysis of exposure, utilization and perceived barriers.

INTRODUCTION: Functional Neurosurgery (FNS) is a non-invasive and highly efficacious neurosurgical subspecialty but lower middle-income countries (LMICs) are disadvantaged in terms of access and availability of FNS. Through this study we have tried to assess the availability, exposure, utilization, and perceived barriers to five major FNS modalities including deep brain stimulation (DBS), vagal nerve stimulation (VNS), stereotactic radiosurgery (SRS), MRI-guided focused ultrasound (MRgfUS) and percutaneous rhizotomy in LMICs. METHODOLOGY: We designed a survey using google forms while following the CHERRIES guidelines. Responses were collected from practicing neurosurgeons, neurosurgical fellows, and residents in LMICs. Statistical analysis was performed using SPSS software 26.0 RESULTS: A total of 100 responses were recorded of which 96 % were males. 68 % worked in an educational setup. Respondents had the most exposure to SRS (36 %) followed by DBS (28 %) while MRgFUS was the least exposed modality (4 %) (p<0.001). For all modalities except MRgFUS, majority of the respondents were 'Fairly confident' (p<0.001). No statistically significant association was observed in the availability of the modalities with the type of working setup. Majority of the respondents did not consider legal issues (p=0.003) and patient preferences (p=0.007) to be perceived barriers for any modality. Accessibility, affordability, Lack of training were not significant factors for any modality except DBS (52 %, p<0.001; 55 %, p<0.001 and 53 %, p=0.002 respectively) CONCLUSION: An integrated approach including international collaborations, traveling fellowships, novel policies must be adopted to enhance the reach of FNS to LMICs to share the extensive neurosurgical burden and to ease the neurosurgical decision making.

Awake versus asleep deep brain stimulation for Parkinson's disease: a comprehensive systematic review and meta-analysis.

OBJECTIVE: Deep brain stimulation (DBS) has become an effective and safe treatment in patients with Parkinson's disease (PD) not responding to conventional treatments. With the growing body of literature regarding the use of DBS in different movement disorders, there remain controversies regarding performing awake or asleep DBS. This systematic review provides the most comprehensive review of the literature comparing the two techniques from various aspects in detail. METHODS: A systematic review of the PubMed, Scopus, Web of Science, and Cochrane Library databases was conducted. All studies comparing any aspects of asleep and awake DBS were included. Risk of bias was assessed using the Risk of Bias in Non-Randomized Studies of Interventions tool. Meta-analysis was conducted with consideration of baseline characteristics. RESULTS: Thirty-one studies with 2563 PD patients were included. A total of 1423 patients underwent asleep DBS. The two groups were comparable regarding their baseline characteristics. The follow-up ranged from 3 to 60 months. The two DBS techniques were comparable in terms of motor symptom improvements and levodopa equivalent daily doses. However, the asleep technique showed slightly better improvements in Mattis Dementia Rating Scale and Parkinson's Disease Questionnaire scores. Moreover, the asleep technique was associated with more surgical adverse events, whereas pneumocephalus and psychological disorders such as mood, affect, and cognitive disorders were more common in the awake technique. Subgroup analyses revealed no significant differences in outcomes between asleep and awake DBS when categorized by targeted brain nuclei, use of intraoperative or preoperative imaging, and whether microelectrode recordings were used. CONCLUSIONS: These findings suggest comparable clinical outcomes between the two DBS approaches. The two methods had their salient differences in terms of lead passes and specific adverse events. The decision to perform awake or asleep DBS should be based on the patient's preference, the surgeon's experience, the availability of advanced intraoperative imaging, and the patient's tolerance for specific adverse events.

Optimizing indirect targeting of the centromedian nucleus for deep brain stimulation by incorporating third ventricular anatomy.

OBJECTIVE: Deep brain stimulation (DBS) of the centromedian nucleus (CM) is used to treat diverse brain diseases including epilepsy, Tourette syndrome, and disorders of consciousness. However, the CM is challenging to visualize on routine MRI. Many surgeons use an indirect targeting method based on established stereotactic coordinates. The authors aimed to quantify how often a DBS electrode's contacts were positioned within the CM using this approach, and to identify alternative indirect coordinates that are more accurate. METHODS: Indirect targeting of the CM was performed on 100 MR images obtained in healthy adults, and the resulting coordinates were warped to a common brain template. To estimate positions of DBS contacts along this trajectory, the authors developed a probable electrode location (PEL) mask, modeled on trajectory angles obtained from prior clinical cases. Euclidean and x, y, and z distances between the centroids of the PEL mask and an atlas-based CM mask were measured and defined as error. The percentage of overlaps between the PEL mask and nearby thalamic nuclei was determined. To assess the clinical utility of this methodology, the analysis was validated using 20 MR images obtained in patients with generalized epilepsy, a common clinical indication for CM-DBS. RESULTS: Using standard indirect coordinates, the authors found the average Euclidean error to be 4.40 ± 1.05 mm, and the x, y, and z errors were 4.19 ± 0.97 mm, 0.73 ± 0.65 mm, and 0.66 ± 0.69 mm, respectively. The PEL mask overlap was 52% with the CM and 65% with the ventral posteromedial nucleus. Variation in third ventricular width was the dominant contributor to these errors (r = -0.71). To overcome this variation, the authors developed alternative indirect coordinates: 4.5 mm lateral to the posterolateral corner of the third ventricle at the level of the posterior commissure. With this refinement, the average Euclidean error was reduced to 1.24 ± 0.5 mm, with 84% of the PEL mask within the CM. CONCLUSIONS: The unavailability of advanced MRI for direct targeting limits access to CM-DBS in resource-constrained neurosurgical programs. Standard indirect coordinates do not provide optimal targeting of the CM, with most contacts laterally placed in the sensory thalamus. The proposed indirect approach may therefore increase the accuracy and availability of CM-DBS, while reducing side effects.

Navigating Challenges and Embracing Opportunities: The Outlook of Functional Neurosurgery in Africa.

This narrative review explores the current landscape of functional neurosurgery in Africa, focusing on the challenges and opportunities facing the field. Drawing upon existing literature and expert insights, the review highlights the scarcity of resources, including trained personnel, infrastructure, and specialized equipment, as major hurdles impeding the widespread adoption of advanced neurosurgical techniques. Despite these challenges, the review identifies a growing recognition of the importance of functional neurosurgery in addressing neurological disorders prevalent across the continent. Efforts to enhance training programs, establish collaborations with international partners, and leverage technology are discussed as promising strategies to overcome logistical barriers. Moreover, the review underscores the significance of addressing cultural beliefs and stigmas surrounding neurological conditions to ensure equitable access to care and promote acceptance of neurosurgical interventions. By navigating these challenges and embracing emerging opportunities, functional neurosurgery in Africa holds the potential to significantly impact neurological health outcomes and enhance overall well-being.

Bilateral Anterior Capsulotomy for Treatment-Resistant Obsessive-Compulsive Disorder.

INTRODUCTION: Ablative surgery is an intervention of last resort for treatment-resistant obsessive-compulsive disorder (TROCD). Our center has been using bilateral anterior capsulotomy (BAC) for the past 20 years for patients eligible for limbic surgery. This report details our experience with BAC for TROCD. METHOD: Five patients with OCD met eligibility criteria for BAC. Entry protocols were complex and took around 6 months to complete. Stereotactic radiofrequency was used to produce the capsulotomies. Lesion length varied between 5.7 and 16.9 mm in the coronal plane. Patients were followed between 4 and 20 years. RESULTS: All 5 patients (100%) were responders as defined by the widely accepted criteria of a reduction of ≥35% in Yale-Brown Obsessive Compulsive Scale (YBOCS) score at 18-month follow-up. Four patients remained responders at the 48 months. One patient was lost to follow-up. Responder status when viewed from the perspective of the YBOCS was sustained over the 4- to 20-year follow-up with one relapse 19 years postsurgery when medications were discontinued. Real-world psychiatric outcomes were different as other vulnerabilities surfaced illustrating the multifactorial determinants of mental health. No patient had any significant long-term neurocognitive or physical side effects. CONCLUSION: BAC should remain an option of last resort for patients with severe OCD who remain unresponsive to all other interventions.

Functional mapping of movement and speech using task-based electrophysiological changes in stereoelectroencephalography.

OBJECTIVE: Stereoelectroencephalography (SEEG) has become the predominant method for intracranial seizure localization. When imaging, semiology, and scalp EEG findings are not in full agreement or definitively localizing, implanted SEEG recordings are used to test candidate seizure onset zones (SOZs). Discovered SOZs may then be targeted for resection, laser ablation, or neurostimulation. If an SOZ is eloquent, resection and ablation are both contraindicated, so identifying functional representation is crucial for therapeutic decision-making. The authors present a novel functional brain mapping technique that utilizes task-based electrophysiological changes in SEEG during behavioral tasks and test this in pediatric and adult patients. METHODS: SEEG was recorded in 20 patients with epilepsy who ranged in age from 6 to 39 years (12 female, 18 of 20 patients < 21 years of age) and underwent implanted monitoring to identify seizure onset. Each performed 1) visually cued simple repetitive movements of the hand, foot, or tongue while electromyography was recorded; and 2) simple picture-naming or verb-generation speech tasks while audio was recorded. Broadband changes in the power spectrum of the SEEG recording were compared between behavior and rest. RESULTS: Electrophysiological functional mapping of movement and/or speech areas was completed in all 20 patients. Eloquent representation was identified in both cortex and white matter and generally corresponded to classically described functional anatomical organization as well as other clinical mapping results. Robust maps of brain activity were identified in healthy brain, regions of developmental or acquired structural abnormality, and SOZs. CONCLUSIONS: Task-based electrophysiological mapping using broadband changes in the SEEG signal reliably identifies movement and speech representation in pediatric and adult epilepsy patients.

Preclinical evaluation of transaxial intraputaminal trajectory for enhanced distribution of grafted cells in Parkinson's disease.

OBJECTIVE: The objective of this study was to develop and evaluate the feasibility and safety of a novel transaxial surgical approach for the delivery of human induced pluripotent stem cell-derived dopaminergic neuroprogenitor cells (DANPCs) into the putamen nucleus using nonhuman primates and surgical techniques and tools relevant to human clinical translation. METHODS: Nine immunosuppressed, unlesioned adult cynomolgus macaques (4 females, 5 males) received intraputaminal injections of vehicle or DANPCs (0.9 × 105 to 1.1 × 105 cells/µL) under real-time intraoperative MRI guidance. The infusates were combined with 1-mM gadoteridol (for intraoperative MRI visualization) and delivered via two tracks per hemisphere (ventral and dorsal) using a transaxial approach. The total volumes of infusion were 25 µL and 50 µL for the right and left putamen, respectively (infusion rate 2.5 µL/min). Animals were evaluated with a battery of clinical and behavioral outcome measures and euthanized 7 or 30 days postsurgery; full necropsies were performed by a board-certified veterinary pathologist. Brain tissues were collected and processed for immunohistochemistry, including against the human-specific marker STEM121. RESULTS: The optimized surgical technique and tools produced successful targeting of the putamen via the transaxial approach. Intraoperative MR images confirmed on-target intraputaminal injections in all animals. All animals survived to scheduled termination without clinical evidence of neurological deficits. The first 4 animals to undergo surgery had mild brain swelling noted at the end of surgery, of which 3 had transient reduced vision; administration of mannitol therapy and reduced intravenous fluid during the surgical procedure addressed these complications. Immunostaining against STEM121 confirmed the presence of grafted cells along the injection track within the targeted putamen area of DANPC-treated animals. All adverse histological findings were limited in scope and consistent with surgical manipulation, injection procedure, and postsurgical inflammatory response to the mechanical disruption caused by the cannula insertion. CONCLUSIONS: The delivery system, injection procedure, and DANPCs were well tolerated in all animals. Prevention of mild brain swelling by mannitol dosing and reduction of intravenous fluids during surgery allowed visual effects to be avoided. The results of the study established that this novel transaxial approach can be used to correctly and safely target cell injections to the postcommissural putamen and support clinical investigation.

Salvaging the transected hypoglossal nerve using descendens hypoglossi in patients undergoing hypoglossal-facial nerve anastomosis for facial palsy: a randomized clinical trial.

OBJECTIVE: Hypoglossal-facial nerve anastomosis (HFA) is the most commonly used surgical treatment for severe facial palsy that does not respond to conservative treatments. A major complication of HFA is the loss of tongue function. The authors aimed to evaluate whether anastomosing the transected hypoglossal nerve using the ramus descendens hypoglossi could prevent tongue deviation and dysfunction in patients undergoing HFA. METHODS: In this randomized trial, adult patients with severe peripheral facial palsy (House-Brackmann grade V or VI) who did not respond to at least 6 months of conservative treatment were randomized at a 1:1 ratio to undergo either HFA alone (control group) or HFA plus anastomosis between the hypoglossal nerve and descendens hypoglossi (intervention group). The primary endpoint was tongue deviation angle at 12 months. Key secondary endpoints included tongue disability (chewing difficulty, swallowing defect, and articulation defect), tongue disability index (TDI; range 1-4, with a higher score indicating more severe disability), and facial nerve function. RESULTS: Twenty patients were enrolled (10 in each group). At 12 months, the tongue deviation angle was significantly lower in the intervention group than in the control group (7.8° ± 5.1° vs 23.6° ± 9.6°, p < 0.001). Although not statistically significant, the intervention group had lower rates of chewing difficulty (1/10 vs 3/10, p = 0.58), swallowing defect (1/10 vs 5/10, p = 0.14), and articulation defect (2/10 vs 6/10, p = 0.17). TDI was significantly lower in the intervention group (1.5 ± 0.6 vs 2.5 ± 0.3, p < 0.001). The percentage of the patients achieving House-Brackmann grade II or III was 80% in each group. CONCLUSIONS: Anastomosis of the descendens hypoglossi to the transected hypoglossal nerve attenuated tongue deviation in patients undergoing HFA for facial palsy, without compromising facial nerve function. Clinical trial registration no: ChiCTR2000034372 (Chinese Clinical Trials Registry).

Radiographic abnormalities and their clinical significance in patients with Parkinson disease who receive deep brain stimulation implants.

OBJECTIVE: Preoperative MR images obtained in patients with Parkinson disease (PD) undergoing deep brain stimulation (DBS) often reveal incidental radiographic abnormalities (RAs). These findings range from small changes to gross pathologies. The effect of these findings on patients' clinical outcomes is unknown. The authors characterized RAs in patients with PD who underwent DBS and assessed clinical outcomes. METHODS: Records of patients at the authors' institution with PD who underwent MRI for DBS electrode implantation from 2010 through 2022 were reviewed. RAs were identified from the official preoperative MRI reports. RAs were grouped into four general categories (ischemic changes, atrophy or degenerative changes [ADCs], structural abnormalities, and tumors) and correlated with clinical outcomes (including subjective clinical response, levodopa equivalent dose [LED], and Unified Parkinson's Disease Rating Scale Part III [UPDRS] score) at the 1-year and last available follow-ups. RESULTS: In this review, 160 patients were identified for initial analysis, with 135 presenting with ≥ 1 RAs. Of these 135 patients, 69.4% (111/160) had ischemic vascular changes, 39.4% (63/160) had ADCs, 16.9% (27/160) had structural changes, and 1.9% (3/160) had tumors. No differences in preoperative LED or UPDRS score were observed between these groups. After DBS, no differences in outcomes were observed between patients with RAs and those without RAs for both the 1-year and last follow-up time points, including mortality rates and times. Structural lesions were associated with lower mortality rates (OR 0.1, p = 0.04). ADCs were associated with a worse subjective clinical response at the 1-year (OR 0.50, p = 0.04) and last (OR 0.49, p = 0.03) follow-ups, but subjectively worse responses were not correlated with worse objective outcome measures. CONCLUSIONS: Most RAs have no significant effect on clinical outcomes in PD patients undergoing DBS. Generalized ADCs may be associated with poorer subjective responses and may warrant further discussion with the patient if diagnosed on preoperative MRI.

Factors influencing disparities in epilepsy surgery: analysis of the National Inpatient Sample and Kids' Inpatient Database.

OBJECTIVE: Despite the proven efficacy of surgical intervention for achieving seizure freedom and improved quality of life for many epilepsy patients, this treatment remains underutilized. In this study, the authors assessed sociodemographic trends in epilepsy surgery in the National Inpatient Sample (NIS) and the Kids' Inpatient Database (KID) and sought to determine whether disparities in surgical intervention for epilepsy may be attributed to insurance and comorbidity status. METHODS: This cross-sectional study utilized data from the NIS database and KID from the Healthcare Cost and Utilization Project between the years 2012 and 2018. Outcomes of interest were rates of neurosurgical intervention, including resection, neuromodulation, or laser ablation. The authors utilized logit regression models to test the association between rates of neurosurgical intervention and the variables of interest and calculated the adjusted mean proportion of patients who received surgery using marginal effects. RESULTS: Of 336,015 admissions with intractable epilepsy in the NIS, 6.1% were patients who underwent neurosurgical treatment. Of 39,655 admissions from KID, 5.0% received surgical treatment. Private insurance was associated with a greater odds of surgical intervention compared with Medicaid (NIS: OR 1.63, KID: OR 1.62; p < 0.001). Patients assigned White race had an increased odds ratio of undergoing surgery when compared with those assigned Black race, adjusted for comorbidity burden (NIS: OR 1.59, p < 0.001; KID: OR 1.44, p = 0.027). Patients with an Elixhauser Comorbidity Index score of 0 or 1 were associated with a lower likelihood of surgery when compared to their higher scoring counterparts who had 4 or more comorbidities (NIS: OR 0.74, KID: OR 0.62; both p < 0.001). CONCLUSIONS: This study demonstrates that marginalized patients and those with Medicaid had decreased odds of neurosurgical intervention for epilepsy. Results of this research support the need for increased attention toward epilepsy patients from marginalized groups. Further investigation into the root cause of socioeconomic inequities in epilepsy surgery is necessary.

Precision targeting in the globus pallidus interna: insights from the multicenter, prospective, blinded VA/NINDS CSP 468 study.

OBJECTIVE: Deep brain stimulation (DBS) targeting the globus pallidus interna (GPi) has been shown to significantly improve motor symptoms for the treatment of medication-refractory Parkinson's disease. Yet, heterogeneity in clinical outcomes persists, possibly due to suboptimal target identification within the GPi. By leveraging robust sampling of the GPi and 6-month postsurgical outcomes, this study aims to determine optimal symptom-specific GPi DBS targets. METHODS: In this study, the authors analyzed the anatomical lead location and 6-month postsurgical, double-blinded outcome measures of 86 patients who underwent bilateral GPi DBS. These patients were selected from the multicenter Veterans Affairs (VA)/National Institutes of Neurological Disorders and Stroke (NINDS) Cooperative Studies Program (CSP) 468 study to identify the optimal target zones ("sweet spots") for the control of overall motor (United Parkinson's Disease Rating Scale [UPDRS]-III), axial, tremor, rigidity, and bradykinesia symptoms. Lead coordinates were normalized to Montreal Neurological Institute space and the optimal target zones were identified and validated using a leave-one-patient-out approach. RESULTS: The authors' findings revealed statistically significant optimal target zones for UPDRS-III (R = 0.37, p < 0.001), axial (R = 0.22, p = 0.042), rigidity (R = 0.20, p = 0.021), and bradykinesia (R = 0.23, p = 0.004) symptoms. These zones were localized within the primary motor and premotor subdivisions of the GPi. Interestingly, these zones extended beyond the GPi lateral border into the GPi-globus pallidus externa (GPe) lamina and into the GPe, but they did not reach the GPi ventral border, challenging traditional surgical approaches based on pallidotomies. CONCLUSIONS: Drawing upon a robust dataset, this research effectively delineates specific optimal target zones for not only overall motor improvement but also symptom subscores. These insights hold the potential to enhance the precision of targeting in subsequent bilateral GPi DBS surgical procedures.

Deep brain stimulation in Latin America in comparison with the US and Europe in a real-world population: indications, demographics, techniques, technology, and adverse events.

OBJECTIVE: The aim of this study was to provide geographic comparisons of deep brain stimulation (DBS) procedures in Latin America with the US and Europe regarding primary indications, demographic information, clinical and device-related adverse events, technology used, and patient outcomes using the Medtronic Product Surveillance Registry data as of July 31, 2021. METHODS: Two thousand nine hundred twelve patients were enrolled in the registry (2782 received DBS and 1580 are currently active). Fourteen countries contributed 44,100 years of device experience to the registry. DBS centers in Latin America are located in Colombia (n = 3), Argentina (n = 1), Brazil (n = 1), and Mexico (n = 1). Fisher's exact test was used to compare the difference in proportions of categorical variables between regions. The Wilcoxon signed-rank test was used for the EQ-5D index score change from baseline to follow-up. RESULTS: The most common indication for DBS was Parkinson's disease across all regions. In Latin America, dystonia was the second most common indication, compared to essential tremor in other regions. There was a striking finding with respect to age-patients were an average of 10 years younger at DBS implantation in Latin America. This difference was most likely due to the greater number of patients with dystonia receiving the device implants. The intraoperative techniques were quite similar, showing the same level of quality and covering the main principles of the surgeries with some variations in the brand of frames, planning software, and microrecording systems. Rechargeable batteries were significantly more common in Latin America (72.37%) than in the US (6.44%) and Europe (9.9%). Staging of the DBS procedure differed, with only 11.84% in Latin America staging the procedure compared with 97.58% and 34.86% in the US and Europe, respectively. The EQ-5D score showed significant improvements in all regions during the first 6-12 months (p < 0.0001). However, the 24-month follow-up only showed an improvement in the scale for Latin America (p < 0.0001). CONCLUSIONS: DBS was performed in Latin America with similar indications, techniques, and technology as in the US and Europe. Important differences were found, with Latin America implementing more regular use of rechargeable devices, including younger patients at the time of surgery, and showing more sustained quality of life improvements at 24 months of follow-up. The authors hypothesize that these disparities stem from differences in resources among regions. However, more studies are needed to standardize DBS practice across the world to improve patients' quality of life and provide high-quality care.

White matter characteristics in children with cerebral palsy prior to selective dorsal rhizotomy: a multicenter diffusion tensor imaging study.

OBJECTIVE: The aims of this study were to 1) assess and quantify white matter (WM) microstructural characteristics derived from diffusion tensor imaging (DTI) in children with cerebral palsy (CP) prior to selective dorsal rhizotomy (SDR), and 2) investigate potential associations between WM diffusion properties and gross motor function and spasticity in children with spastic CP who underwent SDR. METHODS: This study is a multisite study based on DT images acquired prior to SDR as well as postoperative outcome data. DTI data collected from two sites were harmonized using the ComBat approach to minimize intersite scanner difference. The DTI abnormalities between children with spastic CP and controls were analyzed and correlated with the severity of impaired mobility based on the Gross Motor Function Classification System (GMFCS). The improvement in gross motor function and spasticity after SDR surgery was assessed utilizing the Gross Motor Function Measure-66 (GMFM-66), the Modified Tardieu Scale (MTS), and the modified Ashworth scale (MAS). Alterations in these outcome measures were quantified in association with DTI abnormalities. RESULTS: Significant DTI alterations, including lower fractional anisotropy (FA) in the genu of the corpus callosum (gCC) and higher mean diffusivity (MD) in the gCC and posterior limb of the internal capsule (PLIC), were found in children in the SDR group when compared with the age-matched control group (all p < 0.05). Greater DTI alterations (FA in gCC and MD in gCC and PLIC) were associated with lower mobility levels as determined based on GMFCS level (p < 0.05). The pre- to post-SDR improvement in motor function based on GMFM-66 was statistically significant (p = 0.006 and 0.002 at 6-month and 12-month follow-ups, respectively). The SDR efficacy was also identified as improving spasticity in lower-extremity muscle groups assessed with the MTS and MAS. Partial correlation analysis presented a significant association between pre- to post-SDR MTS alteration and DTI abnormalities. CONCLUSIONS: The findings in the present study provided initial quantitative evidence to establish the WM microstructural characteristics in children with spastic CP prior to SDR surgery. The study generated data for the association between baseline DTI characteristics and mobility in children with CP prior to SDR surgery. The study also demonstrated SDR efficacy in improving motor function and spasticity based on the GMFM-66, MTS, and MAS, respectively, in association with DTI data.

Outcomes of stereotactic thalamotomy in patients of essential tremor: A systematic review.

BACKGROUND: Essential tremor is a neurological condition associated with movement disorder with more prevalence among adult group of population. The burden of essential tremor is peaking globally but with the advancement in the area of functional neurosurgery such as stereotactic thalamotomy, the quality of life of such patients can be improved drastically. METHODS: This systemic review was conducted in accordance to the guidance of preferred Reporting items for Systematic Review and Meta-Analysis(PRISMA). Databases of "PubMed", "Embase", "Web of Science", "Cinhal Plus", and "Scopus" from inception till 2023 was undertaken. A combination of keywords, Medical Subject Headings (MeSH), and search terms such as Search strategy for PubMed search was as follows: "stereotactic thalamotomy" AND "essential tremor". RESULTS: This systematic review analyzed 9 studies with a total of 274 patients of essential tremor patients. Unilateral thalamotomy was carried out among 268 patients and bilateral thalamotomy in rest of the patients. Vim and Vom nucleus were the site of thalamotmy with ventral intermedius nucleus being the major one. Ten different types of clinical tremor rating scales were used to assess pre operative and post operative improvement in the tremor scales of the individual patients. Dysarthria and limb weakness was noted post operative complication in majority of the cases. CONCLUSION: Our study revealed that stereotactic thalamotomy provided good functional outcome in patients of essential tremor who underwent unilateral thalamotomy compared to bilateral thalamotomy. The positive outcome outweighs the complications in such functional surgery.

Combined neuromodulation and resection for functional cortex epilepsy: a case series.

OBJECTIVE: Medically refractory epilepsy (MRE) often requires resection of the seizure onset zone (SOZ) for effective treatment. However, when the SOZ is in functional cortex (FC), achieving complete and safe resection becomes difficult, due to the seizure network overlap with function. The authors aimed to assess the safety and outcomes of a combined approach involving partial resection combined with focal neuromodulation for FC refractory epilepsy. METHODS: The authors performed a retrospective analysis of individuals diagnosed with MRE who underwent surgical intervention from January 2015 to December 2022. Patients whose SOZ was located in FC and were treated with resection combined with simultaneous implantation of a focal neuromodulation device (responsive neurostimulation [RNS] device) with more than 12 months of follow-up data were included. All patients underwent a standard epilepsy preoperative assessment including intracranial electroencephalography and extraoperative stimulation mapping. Resections were performed under general anesthesia, followed by the concurrent implantation of an RNS device. RESULTS: Seven patients (4 males, median age 32.3 years, all right-handed) were included. The median interval from seizure onset to surgery was 17.4 years. The epileptogenic network included sensorimotor areas (cases 2, 3, and 6), visual cortex (case 1), language areas (cases 4 and 7), and the insula (case 5). The median follow-up was 3 years (range 1-5.8 years). No significant changes in neuropsychological tests were reported. One permanent nondisabling planned neurological deficit (left inferior quadrantanopia) was observed. Six patients had stimulation activated at a median of 4.7 months after resection. All patients achieved good seizure outcomes (5 with Engel class I and 2 with Engel class II outcomes). CONCLUSIONS: Maximal safe resection combined with focal neuromodulation presents a promising alternative to stand-alone resections for MRE epileptogenic zones overlapping with functional brain. This combined approach prioritizes the preservation of function while improving seizure outcomes.

Microvascular decompression for intermediate nerve neuralgia: a case report and literature review.

Intermediate nerve neuralgia (INN) is a rare craniofacial pain syndrome. The diagnosis of INN is challenging because of the complex ear sensory innervation that results in a clinical overlap with both trigeminal neuralgia (TN) and glossopharyngeal neuralgia (GPN). A 76-year-old woman with a remarkable medical history presented with right otalgia and mandibular pain for 7 years. Neurological examination revealed a diminished sensation in the distribution of the intermediate nerve (IN). Magnetic resonance imaging demonstrated an impression of the anterior inferior cerebellar artery (AICA) on the facial-vestibulocochlear nerve complex (VII/VIII complex). The patient underwent microvascular decompression (MVD) after long-term oral medication. We confirmed that the responsible vessel was close to the VII/VIII complex and isolated the vessel under the microscope via a right-sided suboccipital retrosigmoid approach. The patient's otalgia and mandibular pain disappeared after the operation. There were no additional neurological deficits. In conclusion, MVD is a safe and feasible option for patients with INN who fail to respond to adequate pharmacotherapy.

[Problems in organizing neurosurgical care for patients with Parkinson's disease in the Russian Federation]. / Problemy organizatsii neirokhirurgicheskoi pomoshchi patsientam s bolezn'yu Parkinsona v Rossiiskoi Federatsii.

BACKGROUND: Currently, there are some problems in the Russian Federation complicating development of neurosurgical care for patients with Parkinson's disease (PD). MATERIAL AND METHODS: In 2022, neurologists - movement disorders specialists were surveyed to analyze situation with PD pharmacological treatment and referral of patients for surgical treatment in Russian constituent entities. Data on neurosurgical treatment of PD were obtained by collecting information on the surgical activity of medical institutions in the Russian Federation. Most hospitals involved in PD treatment took part in this study. RESULTS: The state of neurosurgical care for patients with PD is analyzed and possible ways to improve the quality of treatment are discussed. CONCLUSION: Over the past 20 years, a system of neurosurgical care for patients with PD has been formed in 14 centers in the Russian Federation (2022). Obstacles to its further development can be divided into 3 categories: problems of patient selection and routing, complexity of organization and financing surgeries, and imperfect postoperative patient management. Ways to overcome these obstacles imply expanding the network of centers for extrapyramidal diseases, development of domestic neurostimulation systems, improving the distribution of quotas taking into account the capabilities of hospitals, specialized training of neurologists for extrapyramidal centers and neurosurgeons for deep brain stimulation centers, adequate financing and systematization of postoperative management of patients with PD.

Focal selective dorsal rhizotomy and concurrent deformity correction: a combined approach.

OBJECTIVE: Selective dorsal rhizotomy (SDR) is a neurosurgical procedure to reduce spasticity in children with cerebral palsy and spastic diplegia. The authors developed a procedure called focal SDR for children with spasticity predominantly in the L5 or S1 motor distribution, which can be combined with orthopedic correction of fixed soft-tissue or bony deformity. The authors describe in detail the technique of minimally invasive focal SDR and propose selection criteria. METHODS: The authors conducted a retrospective study of patients who underwent focal SDR at their institution and underwent baseline and 1-year postoperative 3D gait analysis. Modified Ashworth scale (MAS) and Gait Deviation Index (GDI) scores were the primary outcome measures. RESULTS: Ten patients met the study criteria, all with an underlying diagnosis of cerebral palsy. All underwent focal SDR at the unilateral or bilateral S1 level, and 4 additionally underwent focal SDR at the L5 level unilaterally or bilaterally. All but 1 patient underwent concurrent orthopedic surgery. The improvement in spasticity of the plantar flexors, as measured by the MAS score, was 2.2 (p < 0.001). In the patients who underwent L5 focal SDR, there was an improvement in the hamstring MAS score of 1.4 (p = 0.004). The mean improvement in the GDI score following focal SDR was 11 (range -6 to 29, p < 0.001). CONCLUSIONS: Focally impairing spasticity in the gastrocsoleus complex and/or hamstrings muscle group in the setting of less functionally impactful proximal tone is extremely common in cerebral palsy. The novel technique of focal SDR, combined with orthopedic intervention, improves spasticity scores and overall gait mechanics. Further investigation is warranted to define the ideal candidacy and outcomes.

Dosimetric Comparison of Dedicated Radiosurgery Platforms for the Treatment of Essential Tremor: Technical Report.

Essential tremor (ET) is one of the most common adult movement disorders. As the worldwide population ages, the incidence and prevalence of ET is increasing. Although most cases can be managed conservatively, there is a subset of ET that is refractory to medical management. By virtue of being "reversible", deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) of the thalamus is one commonly accepted intervention. As an alternative to invasive and expensive DBS, there has been a renaissance in treating ET with lesion-based approaches, spearheaded most recently by high-intensity focused ultrasound (HIFU), the hallmark of which is that it is non-invasive. Meanwhile, stereotactic radiosurgical (SRS) lesioning of VIM represents another time-honored lesion-based non-invasive treatment of ET, which is especially well suited for those patients that cannot tolerate open neurosurgery and is now also getting a "second look". While multiple SRS platforms have been and continue to be used to treat ET, there is little in the way of dosimetric comparison between different technologies. In this brief technical report we compare the dosimetric profiles of three major radiosurgical platforms (Gamma Knife, CyberKnife Robotic Radiosurgery, and Zap-X Gyroscopic Radiosurgery (GRS)) for the treatment of ET. In general, the GRS and Gamma Knife were shown to have the best theoretical dosimetric profiles for VIM lesioning. Nevertheless the relevance of such superiority to clinical outcomes requires future patient studies.