INTRODUCTION:MRI-guided focused ultrasound (MRgFUS) thalamotomy has demonstrated efficacy in tremor relief; however, tremor recurrence may occur. For patients experiencing such recurrence, deep brain stimulation (DBS) presents a viable alternative. This study reports our findings on the application of DBS following MRgFUS. METHODS:We evaluated four right-handed patients diagnosed with essential tremor (ET), with a mean age of 65 years (range 47-76); Three of them male and one female. Tremor was assessed using Fahn-Tolosa-Marin score (CRST) and hemi-CRST scores, while quality of life was assessed using quality of life in essential tremor questionnaire (QUEST). A responder analysis using ≥50% improvement cut-off was used for evaluation. These patients exhibited tremor recurrence at a mean time of 5 months post-MRgFUS. DBS electrodes were implanted bilaterally traversing the ventro-intermediate (VIM) nucleus of the thalamus and the posterior subthalamic area (PSA) in two patients, one patient had electrodes implanted to the VIM alone and another patient had the PSA as an only target. RESULTS:Responder analysis of hemi-CRST scores for the treated hand post-DBS showed improvement in patient 3 and a borderline positive response in patient 1 (0.44), whereas patients 2 and 4 had negative values, suggesting worsening post-DBS. Total CRST responder analysis after DBS showed improvement in patients 1, 3, and 4, while patient 2 showed a negative response. Quality-of-life outcomes were heterogeneous: patient 1 demonstrated sustained QUEST improvement after both MRgFUS and DBS, patients 2 and 4 showed worsening, and patient 3 showed improvement after MRgFUS but worsened after DBS. Adverse events included three patients developed stimulation induced gait disturbance, two of them also had stimulation induced dysarthria. CONCLUSION:The effects of DBS following MRgFUS in ET patients with tremor recurrence are not well characterized. Our single-center experience suggests that DBS can be effective in select patients with manageable adverse events, highlighting the importance of careful patient selection. Further studies are warranted to comprehensively evaluate this sequential treatment approach.
Objectives The Unified Parkinson's Disease Rating Scale (UPDRS Part III), is often not obtained post-operatively in routine clinical practice, limiting objective assessment of treatment response following deep brain stimulation (DBS). Natural language processing (NLP) offers a potential approach to use narrative clinical documentation to predict motor outcomes and evaluate therapeutic responsiveness when formal post-operative scoring is unavailable. Methods Neurology notes and UPDRS Part III assessments were obtained from 25 patients with Parkinson disease (PD) pre- and post-operatively. DBS response was defined as percent improvement in UPDRS Part III from the pre-operative OFF-medication state to the post-operative DBS/medication ON assessment. We assessed whether UPDRS Part III scores could be predicted from clinic notes and whether improvement could be predicted from pre-operative notes. Four NLP approaches were evaluated: TF-IDF with linear models, BERT-base, ClinicalBERT, and Bio-ClinicalBERT embeddings. Models were assessed using leave-one-out cross-validation, with performance evaluated using mean absolute error, coefficient of determination (R²), Spearman correlation, and area under the ROC curve. Results All approaches differentiated pre-operative notes from post-operative notes. The TF-IDF model demonstrated moderate accuracy at predicting UPDRS Part III total scores and percentage change. Several individual motor subscores demonstrated significant correlations between predicted and observed values, including tremor, rigidity, and limb agility measures. Tremor-dominant and rigidity-bradykinesia phenotypes were associated with lower prediction error, whereas the PIGD phenotype showed increased error when predicting postoperative motor improvement. Conclusions These findings support the feasibility of using NLP to detect signal in routine DBS clinical documentation, but they should be interpreted as exploratory. NLP-derived outputs may complement, but should not replace, formal UPDRS-III assessment.
INTRODUCTION:To evaluate clinical outcomes and identify patient- and treatment-related predictors of pain relief onset, long-term pain control, and sensory dysfunction in patients with medically refractory trigeminal neuralgia (TN) treated with CyberKnife radiosurgery (CKRS), incorporating radiobiologic modeling of delivered doses. METHODS:A retrospective study was performed across five international institutions, analyzing 560 TN patients treated with CKRS between 2009 and 2024. Demographic, clinical and dosimetric data were collected. Pain and sensory dysfunction outcomes were evaluated using the modified Barrow Neurological Institute Pain Intensity (mBNI-PIS) and Facial Numbness Scales (BNI-FNS), respectively. Logistic regression and Cox proportional hazards models were used to identify predictors of pain relief, latency, long-term pain control, and facial numbness risk. Biological effective dose (BED) distributions were calculated accounting for sublethal DNA damage repair and treatment delivery timelines; retreatments were excluded. RESULTS:Pain relief (defined as BNI-PIS I-IIIa) was achieved in 92% of patients with a median latency of 12-weeks (range: 0 - 76 weeks). The median follow-up was 50 months (range: 6 - 175 months). Actuarial freedom-from-pain rates were 85%, 78%, 68% and 58% at 12-, 24-, 60- and 120-months, respectively. Bothersome and severely bothersome facial numbness occurred in 5% and 1% of patients, respectively, while an additional 21% experienced non-bothersome numbness. Multivariate analysis identified older age, higher target maximum dose and BED (>1607 Gy2.47) values, and shorter beam-on- and treatment-time as predictors of early pain relief (< 30-days), whereas neurovascular conflict (NVC) predicted delayed response. Older age and NVC were also associated with pain control maintenance. Multiple sclerosis predicted both reduced treatment response and increased pain recurrence risk. Maximum target dose of 77 Gy, and integral BED of 59 mJ2.47 (corresponding to a target volume of 47 mm3) were independently associated with a 10% hypoesthesia risk. CONCLUSION:CKRS provides high pain relief onset (92%) and durable pain control (68% at 60-months) in TN patients, with low bothersome (5%) and severely bothersome (1%) facial numbness rates. The identified dosimetric thresholds offer practical guidance for optimizing treatment planning while balancing hypoesthesia risk.
INTRODUCTION:Subthalamic nucleus deep brain stimulation (STN-DBS) is an established treatment for advanced Parkinson's disease (PD). While traditionally reserved for later stages, growing evidence suggests earlier intervention may offer benefits. This study compares outcomes of very-early versus early DBS in a single-center cohort. METHODS:This retrospective study included 65 PD patients undergoing STN-DBS (2015-2025), grouped as very-early (<5 years disease duration, n=32) or early (≥5 years, n=33). Groups were comparable in age, sex, and disease severity. Results included Hoehn & Yahr (H&Y), Unified Parkinson's Disease Rating Scale pt III (UPDRS-III), Mini Mental State Examination (MMSE), and levodopa equivalent daily dose (LEDD) assessed preoperatively, early postoperatively, and at 3 years. RESULTS:Mean age was 62.45 ± 8.79 years; 69.2% were male. Both groups showed significant postoperative improvement in H&Y (p<0.001), with partial decline at 3 years, though still better than baseline. No significant group-time interaction was observed for H&Y or UPDRS-III, indicating similar long-term motor outcomes. The group-by-time interaction for LEDD was significant (p=0.002), reflecting different medication trajectories: both groups converged to similar postoperative LEDD levels despite the early DBS group starting from a substantially higher baseline (1010±514 vs 676±394mg/day; p=0.005). Multivariable regression showed that baseline preoperative LEDD was the dominant predictor of postoperative medication reduction; after adjustment, surgical timing was no longer significantly associated with LEDD reduction (p=0.622). Very-early DBS patients had lower early postoperative H&Y scores (p=0.022). Six patients were reclassified as PD-plus during follow-up; sensitivity analyses yielded consistent results. CONCLUSION:Both very-early and early STN-DBS provide significant short-term motor benefits, though some decline occurs over time. Very-early DBS was associated with greater postoperative medication reduction and more favorable early functional outcomes, while long-term motor outcomes remained comparable between groups. However, differences in baseline medication burden may have contributed to the observed LEDD reduction patterns.
INTRODUCTION:Restless legs syndrome (RLS) is a lifelong disorder characterized by recurrent, uncomfortable sensations and irresistible urges to move the legs that peak in the evening. Spinal cord stimulation (SCS) is a longstanding neuromodulation treatment for chronic neuropathic pain with emerging evidence of potential effectiveness towards RLS through a potential shared pathophysiology of central sensitization. OBJECTIVE:To evaluate whether SCS may improve RLS symptoms and/or sleep disturbances in chronic pain patients with co-morbid RLS who received SCS for chronic pain. METHODS:A retrospective review of our institution's electronic health record system was performed to identify patients who received SCS for chronic pain with a concomitant RLS diagnosis. Patients who had a diagnosis of RLS in their chart were secondarily confirmed to have RLS using the Cambridge-Hopkins RLS Questionnaire via telephone. The International Restless Leg Syndrome Study Group Rating Scale (IRLSS) and multiple Patient-Recorded Outcomes Measurements (NIH PROMIS) of sleep data were obtained via telephone with patients recalling their symptoms pre- and post-SCS implantation. RESULTS:A group of 11 patients with an existing SCS system implanted for chronic pain and co-morbid RLS confirmed on the Cambridge-Hopkins questionnaire were identified. The IRLS summed score showed a statistically significant (p=0.0343) improvement with a large effect size (r=0.64) indicating that overall symptom severity measured by the IRLS scale decreased significantly with SCS. There was also a significant (p=0.0223) reduction with a large effect size (r=0.69) in the summed NIH PROMIS sleep-related impairment scores, suggesting that SCS had a substantial positive impact on sleep-related impairments. Contrary to this, insignificant (p=0.778) changes were observed in the summed NIH PROMIS sleep disturbance scores with a small effect size (r=0.09). CONCLUSION:SCS has been shown to be an effective, novel treatment for chronic pain but also has positive effects on medication refractory RLS. While this small, retrospective study is limited by recall bias, it provides further evidence of SCS serendipitously improving RLS symptoms. Future prospective research evaluating the effects of SCS on RLS symptoms, pathophysiology, and sleep are needed to further evaluate this phenomenon.
INTRODUCTION:Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an efficient treatment for advanced Parkinson's disease (PD), when oral medication no longer provides satisfactory symptom control or causes disabling side effects. However, long-term outcomes vary considerably, and reliable preoperative biomarkers remain lacking. Dopamine transporter single-photon emission computed tomography (DAT SPECT) provides an indirect in vivo measure of presynaptic striatal dopaminergic degeneration in the basal ganglia. In patients evaluated for STN-DBS, DAT SPECT with [123I]FP-CIT supported the clinical diagnosis. This study aimed to examine whether preoperative DAT SPECT predicts the long-term outcome after STN-DBS surgery. METHODS:Fifty-five patients with PD underwent DAT SPECT before STN-DBS surgery. Motor symptoms were assessed in ON and OFF medication states before surgery, and at long-term follow-up, 8-14 years after surgery. Cognition was assessed before surgery and at the long-term follow-up, and clinical data were curated retrospectively from medical records. RESULTS:Lower DAT striatal specific binding ratio (SBR) significantly correlated with longer disease duration, indicating greater dopaminergic loss. Reduced striatal SBR predicted increased mortality during the long-term follow-up. Regional analyses revealed that this association was driven by the caudate nucleus. Furthermore, greater caudate compared to putaminal involvement, reflected by a higher putaminal/caudate uptake ratio, was related to longer disease duration and increased mortality. Preoperative DAT SPECT measures were not associated with DBS effect, cognitive function, or depression. CONCLUSION:Dopamine transporter imaging provides valuable insight into the pathophysiology and disease progression of PD. Although DAT SPECT did not predict the therapeutic effect of STN-DBS, this study demonstrates that DAT SPECT captures aspects of disease progression and survival in PD. These results highlight the value of assessing the dopaminergic system before advanced treatment, as DAT SPECT may provide prognostic indicators that could complement the preoperative evaluation.
INTRODUCTION:Deep brain stimulation (DBS) hardware infection is a serious complication with heterogeneous presentations and no standardized management guidelines. Management ranges from hardware-sparing (HS) washout to partial (PE) or complete explantation (CE). This study aimed to evaluate outcomes of initial management strategies and identify factors associated with treatment failure and escalation. METHODS:We conducted a single-center retrospective review of adult DBS patients (2002-2020) who required surgery for first-time and recurrent hardware infection or wound erosion. Treatment success was defined as infection clearance without further surgical intervention. Treatment failure was defined as escalation or conversion to a more extensive procedure among those who did not clear the infection.Outcomes were characterized using two complementary definitions - infection clearance success rate defined as absence of recurrent DBS-related infection or wound erosion after index management and non-escalation success rate, defined as avoidance to progression of a more advanced surgical strategy after index procedure. Recurrence freedom was evaluated using Kaplan-Meier analysis, and predictors of recurrence were assessed using multivariable Cox proportional hazards regression. RESULTS:Ninety-eight patients were included. Initial management consisted of HS in 39 patients, PE in 37, and CE in 22. Using the infection-clearance definition, success was observed in 38% of HS cases, 62% of PE cases, and 59% of CE cases. When success was defined by avoidance of escalation, HS achieved non-escalation success in 49% of cases and PE in 78%. Recurrence freedom differed significantly by management strategy, with PE and CE demonstrating greater durability than HS (log-rank χ² = 23.98, p < 0.001). In multivariable Cox regression, PE and CE were associated with significantly lower recurrence hazard compared with HS, while erosion at presentation independently predicted recurrence. Disease category was associated with conversion/escalation, with Parkinson's disease patients less likely to undergo escalation, but PD status did not predict recurrence freedom. Despite lower infection-control durability, HS preserved stimulation for a clinically meaningful interval in selected patients. CONCLUSION:DBS infection outcomes reflect the interaction between infection phenotype, management aggressiveness, and patient-centered goals of therapy. PE and CE provide greater recurrence freedom than HS, particularly when infection control is the primary objective. However, HS remains clinically relevant in selected patients because it may preserve therapeutic stimulation and delay or avoid escalation, even when definitive infection clearance is not achieved.
Introduction Post-stroke motor impairment with spastic hemiparesis remains a significant therapeutic challenge, as conventional rehabilitation and pharmacological strategies often fail to achieve sustained functional recovery. Neuromodulation targeting cerebellar pathways, particularly the dentato-rubro-thalamic tract (DRTT), may provide an alternative therapeutic approach. Methods The study reports the first three cases of chronic post-ischemic stroke-related spastic hemiparesis and dystonic features treated with deep brain stimulation (DBS) targeting the DRTT at the level of the dentate nucleus after unsuccessful botulinum toxin therapy and intensive rehabilitation. Directional DBS systems were implanted using tractography-guided targeting. Clinical outcomes were assessed preoperatively and during sequential stimulation at 130 Hz, 70 Hz, and 30 Hz (each for six weeks), followed by a three-week stimulation-off phase. Outcome measures included the Modified Ashworth Scale (MAS), Fugl-Meyer Assessment of the Upper Limb (FMA-UL), Chedoke Arm and Hand Activity Inventory (CAHAI), Unified Dystonia Rating Scale (UDRS), and modified Rankin Scale (mRS). Results FMA-UL scores progressively improved as stimulation frequency decreased, with mean improvements of 12.3% at 130 Hz, 14.7% at 70 Hz, and 18.4% at 30 Hz. A partial decline was observed during the stimulation-off phase (12.2%). Functional performance (CAHAI) showed the greatest improvement at 30 Hz (11.9%) and decreased to 6.6% during the stimulation-off period. Proximal spasticity was modestly reduced in the shoulder and elbow by approximately one MAS point during stimulation but returned to baseline stimulation-off. Distal spasticity remained largely unchanged. Dystonic features demonstrated frequency-dependent improvement, most pronounced at 30 Hz (43.9%), with partial persistence after stimulation discontinuation (27.5%). Global disability (mRS) remained stable or showed mild improvement. Conclusions Preliminary findings suggest that DRTT-targeted cerebellar DBS, particularly at lower frequencies, may offer a promising adjunctive treatment for post-stroke spasticity and motor impairment refractory to conventional therapies. These initial observations from an ongoing clinical trial require confirmation in larger cohorts with extended follow-up.
Background Brain atrophy is common in Parkinson’s disease (PD) and contributes to motor and cognitive decline. However, the predictive value of neuroimaging-based volumetric measures for motor outcomes following deep brain stimulation (DBS) remains unclear. This study examines whether preoperative volumetric assessment can predict motor outcomes after subthalamic nucleus (STN) DBS in PD. Methods Preoperative T1-weighted 3D MP-RAGE MRI scans were analyzed to measure subcortical, ventricular, and cortical volumes using Brainlab software. Motor outcomes were assessed by changes in the Movement Disorder Society - Unified Parkinson’s Disease Rating Scale part III (MDS-UPDRS-III) scores pre- and postoperatively in 39 participants. Stepwise logistic regression was performed to determine associations between brain volumes and DBS response. Results Smaller substantia nigra compacta volume (0.81 [IQR 0.74-0.85] vs 0.72 [IQR 0.69-0.73]), larger ventricular system (26.1 [IQR 21.4-30.05] vs 34.1 [IQR 28.6-40.87]), and lower atrophy ratio (41.76 [IQR 37.59-50.71] vs 29.63 [IQR 25.9-36.55]) were significantly associated with reduced motor improvement following STN-DBS. The predictive model based on these values demonstrated excellent performance (AUC 0.95, 95% CI: 0.87–1; p < 0.01) in forecasting poorer DBS treatment outcomes as measured by the MDS-UPDRS-III scale. Conclusions Our findings highlight the impact of enlargement of ventricular system and brain atrophy, particularly of the substantia nigra, on motor outcomes after STN-DBS. The association between atrophy measures and executive dysfunction suggests that subclinical dementia may underlie poor DBS response. Future studies should further explore the role of neurodegeneration in DBS response to optimize patient selection and electrode targeting.
Background: Deep brain stimulation (DBS) is an established therapy for movement disorders. However, conventional DBS often involves complete scalp shaving and a visible subclavicular incision for implantable pulse generator (IPG) placement, which may cause cosmetic and psychological burden, particularly in younger or female patients. To address these issues, we developed a cosmetic-oriented DBS technique combining a no-shave cranial approach with trans-axillary fossa IPG implantation. Methods: In this single-center retrospective series, we analyzed 60 consecutive patients who underwent DBS implantation using a no-shave cranial approach with trans-axillary fossa IPG placement. Procedural characteristics and postoperative complications were reviewed retrospectively. Results: Sixty patients underwent DBS implantation with this cosmetic-oriented protocol. Mean age at surgery was 50.4 ± 14.7 years and mean follow-up was 31.6 ± 18.3 months. Mean operative time including IPG placement was 159.1 ± 64.4 min (range 70–353). Early postoperative infection occurred in 2 patients (3.3%), both confined to the axillary IPG pocket within 1 month; no cranial infections or hematomas were observed. Non-infectious complications occurred in 3 patients (5.0%) (one cervical extension foreign-body reaction, one cranial insertion-site reaction, and one lateral IPG displacement requiring revision). Mild transient axillary tightness was reported in 10 patients (16.7%) and resolved without intervention. Conclusion: This cosmetic-oriented DBS method demonstrated a low infection rate and consistent concealment of cranial and axillary incisions, with no apparent signal of increased risk in this series. The approach appears technically feasible across different ages and in both sexes, although patient satisfaction was not formally evaluated.
INTRODUCTION:MRI-guided stereotaxy provides high accuracy but is limited by the need for an interventional/intraoperative MRI environment and associated workflow complexity. ClearPoint Software v3.0 extends an established stereotactic workflow to a conventional operating room using intraoperative CT (iCT) imaging. We aimed to evaluate stereotactic accuracy and operative metrics of the ClearPoint frameless iCT image-guided system for deep brain stimulation (DBS) lead implantation. METHODS:We performed a multicenter retrospective review of consecutive DBS lead placement procedures supported by ClearPoint Neuro Navigation System Software Version 3.0 across 7 sites during a limited market release (February 1, 2025-May 1, 2025). Primary outcomes were radial targeting error (distance between planned trajectory endpoint and final device tip position in X-Y) and operative duration (skin incision to closure). RESULTS:Twenty-three procedures were analyzed. Median age was 67 years (range 32-89). Most cases were bilateral (87%, n = 20). Targets included subthalamic nucleus (39%, n = 9), ventral intermediate nucleus (39%, n = 9), and globus pallidus internus (22%, n = 5). Targeting accuracy was high, with median radial error of 0.20 mm on the left (range 0-1.60) and 0.20 mm on the right (range 0-1.0). Median operative duration was 127 min (range 69-225). Median intraoperative scans were 6, and procedures required a median of 2 adjustments per side. CONCLUSION:In this first multi-institution report of ClearPoint Software v3.0 for DBS lead placement, the frameless iCT workflow demonstrated consistent submillimeter accuracy with favorable operative metrics in a standard operating room setting.
INTRODUCTION:Deep brain stimulation (DBS) procedures vary by use of microelectrode recording (MER) and by unilateral or bilateral implantation. Our goal was to quantify national, regional, and state-level trends in total procedures, MER utilization, and unilateral vs. bilateral electrode implantation. METHODS:The Centers for Medicare and Medicaid Services database was queried for patients undergoing DBS procedures from 2013 to 2023 yielding 27,846 total patients. Use of MER, unilateral vs. bilateral DBS electrode implantation, and procedure location were extracted. Data were analyzed using Shapiro-Wilk test, Pearson's Correlation Coefficient, Spearman's Correlation Coefficient, ANOVA or Kruskal-Wallis with post hoc testing, and Benjamini-Hochberg correction. RESULTS:From 2013 to 2023, total DBS electrode implantation procedures did not change significantly. MER+ DBS was more common than MER- DBS across all years, although MER- DBS increased over time (r = 0.94) while MER+ DBS decreased over time (r = -0.75). Bilateral DBS increased (r = 0.86) over time and in 2021 became more common than unilateral DBS, which decreased over time (r = -0.73). Unilateral and bilateral MER- DBS increased (r = 0.84, 0.95), while unilateral MER+ DBS decreased (r = -0.97). All regions had an increase in MER- DBS (r = 0.96, 0.81, 0.94, 0.84, respectively). The West performed the most MER- DBS, while the South performed the most MER+ DBS. The Midwest and West had an increase in percentage of bilateral DBS (r = 0.95, 0.90, respectively). Regional changes favoring MER- DBS and bilateral electrode implantation were noticed in many states. All reported significant outcomes had p < 0.05. CONCLUSION:Nationally, there is a trend towards performing bilateral and MER- DBS. Recently, there are more bilateral than unilateral procedures, but MER+ is still more common than MER-. Regional differences in DBS surgery also exist. These findings have implications for the experience of patients, neurosurgical trainees, and institutions across the USA.
Introduction: Tremor quantification during magnetic resonance-guided focused ultrasound (MRgFUS) for essential tremor remains a clinical challenge. Current methods, such as accelerometry, can still be limited by electromagnetic artifacts in certain cases, magnetic resonance imaging (MRI) incompatibility, and indirect correlation with sonication timing. We aimed to develop a fully MRI-compatible, nonelectrical system capable of continuous, electromagnetically artifact-free tremor monitoring with near-real-time frequency analysis, precisely synchronized with ultrasound delivery. The primary purpose of this tool is to assist with targeting during the verification stage by providing the tremor amplitude in situ. Methods: We designed a pneumatic device using a standard, easily available endotracheal cuff inflated to a fixed pressure, held by the patient during MRgFUS sonications. Tremor-induced pressure fluctuations were transmitted outside the MRI suite and digitized using a custom Arduino-based system. A software tool was implemented to calculate the tremor amplitude in near-real time. Results: The pressure system allowed real-time visualization of the tremor and assessment of the tremor reduction at the verification stage of 10 patients. The mean tremor reduction was 86% immediately after the end of the verification sonication, confirming the correct position of the target. All patients had a lesion at this location except one, in which the target was moved because he experienced sensory side effects. Conclusion: We designed and implemented a near-real-time pressure system for quantification of the tremor amplitude during sonications. The inexpensive and MR-compatible device is easy to implement on patients requiring MRgFUS treatments and avoid the possible loss of information between the temporary tremor reduction and the clinical evaluation.
INTRODUCTION:Essential tremor (ET) is the most common movement disorder, severe and refractory cases of which may benefit from neurosurgical interventions such as magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy. Cerebrovascular diseases are generally considered a contraindication for MRgFUS due to concerns of intracerebral hemorrhage; however, they are a heterogenous group of lesions, with distinct clinical behaviors. We present the first reported case of successful MRgFUS-thalamotomy for ET in a patient with a contralateral thalamic cerebral cavernous malformation (CCM). CASE PRESENTATION:A 78-year-old male with refractory bilateral upper limb postural/action tremor consented and was planned for a left-sided ventral intermediate nucleus (VIM) MRgFUS-thalamotomy. However, brain MRI revealed a right anterior thalamic CCM measuring 1.5 cm. After careful planning, a modified treatment was still carried out by blocking ultrasound trajectories intersecting the CCM (as well as calcifications) and with increased low-medium power sonications (eight sonications targeting 50-55°C). The patient experienced no adverse effects and demonstrated significant tremor improvement, and postoperative imaging confirmed a well-defined lesion without complications. DISCUSSION:The distinct histopathological features of CCMs, including slow flow and the absence of arterial feeders, produce a more favorable profile compared to other cerebrovascular lesions. Avoidance of direct ultrasound trajectories through the malformation, the use of conservative temperatures, and continuous clinical monitoring were critical to ensuring procedural safety and efficacy. This case demonstrates the feasibility of MRgFUS-thalamotomy in carefully selected patients with coexisting CCMs.
Background: Sleep-wake (SW) disorders are common in numerous neurological and psychiatric conditions, yet current treatments often yield incomplete results. Given the subcortical nature of sleep regulation, intracranial stimulation, and particularly deep brain stimulation (DBS), emerges as a promising therapeutic strategy. This narrative review synthesizes preclinical and clinical evidence regarding the effects of DBS and DBS-like invasive stimulation across multiple brain regions implicated in SW control. Additionally, stimulation targeting non-SW-related targets has also shown incidental effects on sleep and wakefulness. Summary: Evidence reveals target- and frequency-dependent effects on sleep architecture and arousal, with notable translational success in Parkinson’s disease and obsessive-compulsive disorder. The discussion addresses three central questions: (1) Which brain areas modulate sleep and wakefulness when stimulated? (2) How do stimulation parameters influence these outcomes? (3) What are the challenges and limitations in moving toward SW-primary indications? Despite encouraging results, variability in reported measures and outcomes underscores the need for objective, standardized sleep measures (polysomnography) and advanced targeting. Key Messages: Overall, this review may assist clinicians in optimizing DBS parameters in patients experiencing SW disturbances and underscores the broader potential of invasive neuromodulation both as a therapeutic strategy and as a tool to better characterize sleep and wakefulness dynamics.
INTRODUCTION:Focused ultrasound ablation (FUSA) is an emerging treatment for essential tremor (ET). While disparities in access to deep brain stimulation for ET have been identified, potential barriers to FUSA remains understudied. METHODS:A single tertiary-care center, mixed methods study was completed of medication-refractory ET patients presenting for FUSA consultation. Baseline demographics and tremor scores were obtained. A semi-structured questionnaire and focus group discussion was implemented to estimate delays in care, quality of life (QOL) differences, and treatment barriers. Quantile regression, log normal regression, and Fisher's exact tests were used in the quantitative statistical analysis. Thematic and descriptive analyses were used for qualitative data. RESULTS:Forty patients, with similar demographics and tremor scores, were enrolled. Patients spent nearly a decade awaiting ET diagnosis and medical treatment, followed by another 4 years before undergoing FUSA consultation. Although there were no significant differences in delays between genders, the mean number of provider contacts prior to diagnosis was significantly higher for women compared to men (7.5 vs. 0.9, p = 0.029). Those with lower socioeconomic status (≤USD 50,000) had significantly longer diagnostic (15 vs. 3.3, p = 0.056) and FUSA consultation delays (35 vs. 10.2, p = 0.015). At presentation, women reported worse QOL (70 vs. 85, p = 0.037) and overall general health status (70 vs. 85, p = 0.013) than men, with tremor significantly impacting their hobbies and leisure subscores. Women cited more hesitation and concerns regarding the surgery than men such as pre-procedure hair shave. Although men reported longer time from failure of medication therapy to FUSA consultation compared to women (4.0 vs. 2.0 years), more men ultimately underwent the procedure (10 vs. 4, p = 0.04). DISCUSSION:We identified a variety of socioeconomic and gender differences along the patient pathway to FUSA for ET. Although women presented with worse QOL because of their tremor, they were still less likely to undergo FUSA compared to men. Further investigation and patient-centered interventions are needed to achieve equity of care in this patient population.
BACKGROUND:Deep brain stimulation (DBS) is an established therapy for Parkinson's disease (PD), dependent on precise electrode placement relative to intended anatomical and functional targets. Post-operative imaging, primarily magnetic resonance imaging (MRI) and computed tomography (CT), is essential for verifying lead position, assessing surgical accuracy, and guiding stimulation programming. SUMMARY:Most centers perform imaging within the first week after surgery, typically using CT or MRI-CT fusion to confirm electrode location and detect complications. CT offers submillimeter resolution (slice thickness 0.5-1.25 mm; voxel ∼0.5 mm) for clear electrode visualization, while MRI (particularly T1-MPRAGE, T2-FLAIR, and GRE sequences) provides superior anatomical contrast and artifact characterization. KEY MESSAGES:Registration between pre- and post-operative scans remains the predominant localization technique, though automated pipelines such as Lead-DBS, Brainlab Elements™, SureTune4™ now achieve consistent precision within ±0.5-1.5 mm across platforms. This review summarizes current post-operative imaging strategies and quantitative localization techniques in DBS for PD. It discusses the advantages and limitations of each modality and outlines future directions in automation, multimodal integration, and personalized imaging pipelines for improving the accuracy, reproducibility, and clinical utility of post-operative DBS assessment.
INTRODUCTION:Parkinson's disease (PD) leads to progressive motor and non-motor deficits that compromise activities of daily living (ADL) and quality of life (QoL). Although bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) is highly effective, its invasiveness restricts use in certain patients. Magnetic resonance-guided focused ultrasound (MRgFUS) subthalamotomy offers a less invasive, lesion-based alternative, but evidence regarding its broader functional impact remains limited. The objective was to assess the effects of unilateral MRgFUS subthalamotomy on motor experiences of daily living (MDS-UPDRS II) and QoL (PDQ-39) in patients with PD. METHODS:Thirty patients with asymmetric PD refractory to optimized dopaminergic therapy underwent unilateral MRgFUS subthalamotomy targeting the dorsolateral STN between June 2021 and June 2024. Evaluations were performed at baseline, 6 months, and 12 months using MDS-UPDRS II-III, PDQ-39, EQ-5D, and Berg Balance Scale. Primary endpoints were changes in MDS-UPDRS II and QoL; secondary outcomes included motor function (MDS UPDRS III), Levodopa Equivalent Daily Dose (LEDD), and safety. RESULTS:Off- and on-state MDS-UPDRS II improved by 38.5% and 45.8% at 6 months (p < 0.01) and by 50% in both states at 12 months (p < 0.01). PDQ-39 ADL subdomain improved by 10.4% at 12 months (p = 0.033), while global QoL indices remained stable. Off-state motor scores improved by 35.9% (p < 0.001), with reductions in rigidity (50%), bradykinesia (52.9%), and tremor (81.7%). LEDD decreased by 22.1% (p = 0.003). Adverse events were mild and transient, including dysarthria, facial asymmetry, and gait disturbance. CONCLUSION:Unilateral MRgFUS subthalamotomy was associated with improvements in motor function and motor-related activities of daily living, with a favorable safety profile. These findings suggest that this approach may represent a potential less invasive therapeutic option for selected patients who are unsuitable for or unwilling to undergo DBS, although results should be interpreted with caution given the study design.
INTRODUCTION:Parkinson's disease (PD) significantly impairs gait, particularly in advanced stages. Deep brain stimulation (DBS) has emerged as a therapeutic option for refractory motor symptoms, yet its effects on locomotion remain heterogeneous. The objective was to synthesize the available biomechanical evidence on changes in spatiotemporal gait parameters in PD patients undergoing DBS. METHODS:We conducted a systematic review and meta-analysis in accordance with PRISMA 2020. We included original studies with pre- and/or post-DBS gait analyses using instrumented technologies. Methodological quality was assessed with the Cochrane Handbook. RESULTS:Nineteen DBS studies were included. The studies exhibited heterogeneous assessment conditions, encompassing different time points before and after surgery, and both on and off medication and stimulation. The targets analyzed included the subthalamic nucleus, the internal segment of the globus pallidus (GPi), and the pedunculopontine nucleus (PPN). The most frequently reported spatiotemporal parameters were gait speed, step and stride lengths, cadence, and double support time. Data acquisition employed optoelectronic systems, pressure platforms, and inertial sensors. CONCLUSION:DBS improves spatiotemporal gait parameters in PD, particularly under active stimulation. However, methodological heterogeneity and the limited representation of GPi and PPN constrain generalizability. Instrumented systems enable objective and reproducible assessment, which is key to optimizing functional follow-up and therapeutic decision-making.
