A knowledge synthesis of health research reporting standards relevant to epilepsy surgery.

OBJECTIVE: Numerous studies have examined epilepsy surgery outcomes, yet the variability in the level of detail reported hampers our ability to apply these findings broadly across patient groups. Established reporting standards in other clinical research fields enhance the quality and generalizability of results, ensuring that the insights gained from studying these surgeries can benefit future patients effectively. This study aims to assess current reporting standards for epilepsy surgery research and identify potential gaps and areas for enhancement. METHODS: The Enhancing the Quality and Transparency of Health Research (EQUATOR) repository was accessed from inception to April 27, 2023, yielding 561 available reporting standards. Reporting standards were manually reviewed in duplicate independently for applicability to epilepsy and/or neurosurgery research. The reporting standards had to cover the following aspects in human studies: (1) reporting standards for epilepsy/epilepsy surgery and (2) reporting standards for neurosurgery. Disagreements were resolved by a third author. The top five neurosurgery, neurology, and medicine journals were also identified through Google Scholar's citation index and examined to determine the relevant reporting standards they recommended and whether those were registered with EQUATOR. RESULTS: Of the 561 EQUATOR reporting standards, 181 were pertinent to epilepsy surgery. One was related to epilepsy, six were specific to surgical research, and nine were related to neurological/neurosurgical research. The remaining 165 reporting standards were applicable to research across various disciplines and included but were not limited to CONSORT (Consolidated Standards of Reporting Trails), STROBE (Strengthening the Reporting of Observational Studies in Epidemiology), and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). None of these required reporting factors associated with epilepsy surgery outcomes, such as duration of epilepsy or magnetic resonance imaging findings. SIGNIFICANCE: Reporting standards specific to epilepsy surgery are lacking, reflecting a gap in standards that may affect the quality of publications. Improving this gap with a set of specific reporting standards would ensure that epilepsy surgery studies are more transparent and rigorous in their design.

Characterization of anti-seizure medication reduction and discontinuation rates following epilepsy surgery.

OBJECTIVE: Many patients pursue epilepsy surgery with the hope of reducing or stopping anti-seizure medications (ASMs), in addition to reducing their seizure frequency and severity. While ASM decrease is primarily driven by surgical outcomes and patient preferences, preoperative estimates of meaningful ASM reduction or discontinuation are uncertain, especially when accounting for the various forking paths possible following intracranial EEG (iEEG), including resection, neuromodulation, or even the absence of further surgery. Here, we characterize in detail the ASM reduction in a large cohort of patients who underwent iEEG, facilitating proactive, early counseling for a complicated cohort considering surgical treatment. METHODS: We identified a multi-institutional cohort of patients who underwent iEEG between 2001 and 2022, with a minimum of two years follow-up. The total number of ASMs prescribed immediately prior to surgery, choice of investigation modality, and subsequent surgical treatment were extracted for each patient. Primary endpoints included decreases in ASM counts from preoperative baseline to various follow-up intervals. RESULTS: A total of 284 patients were followed for a median of 6.0 (range 2,22) years after iEEG surgery. Patients undergoing resection saw an average reduction of âˆ¼ 0.5 ASMs. Patients undergoing neuromodulation saw no decrease and trended towards requiring increased ASM usage during long-term follow-up. Only patients undergoing resection were likely to completely discontinue all ASMs, with an increasing probability over time approaching âˆ¼ 10 %. Up to half of resection patients saw ASM decreases, which was largely stable during long-term follow-up, whereas only a quarter of neuromodulation patients saw a reduction, though their ASM reduction decreased over time. CONCLUSIONS: With the increasing use of stereotactic EEG and non-curative neuromodulation procedures, realistic estimates of ASM reduction and discontinuation should be considered preoperatively. Almost half of patients undergoing resective surgery can expect to reduce their ASMs, though only a tenth can expect to discontinue ASMs completely. If reduction is not seen early, it likely does not occur later during long-term follow-up. Less than a third of patients undergoing neuromodulation can expect ASM reduction, and instead most may require increased usage during long-term follow-up.

Foramen ovale electrode investigation in the era of SEEG: Results and a reappraisal.

INTRODUCTION: Patients with medication-resistant disabling epilepsy should be considered for potential epilepsy surgery. If noninvasive techniques are unable to identify the location of the seizure onset zone (SOZ), it becomes necessary to consider intracranial investigations. Stereo-electroencephalography (SEEG) is currently the preferred method for such monitoring, however foramen ovale (FO) electrodes offer a less invasive alternative that may be suitable in certain situations. Previous studies have demonstrated the effectiveness of FO electrodes in suspected mesial temporal epilepsy, nevertheless, increased experience with FO electrode use could further enhance their safety and efficacy. Therefore, we conducted an analysis of recent FO electrode investigations to assess their utility in surgical decision making, post resection outcomes, and complication rates. METHODS: We conducted a retrospective analysis of 61 patients who underwent FO placement at Mass General Brigham between 2009 and 2020. Patient and seizure characteristics, preoperative investigation data, and seizures outcomes were collected. In addition, identified predictors of FO utility using logistic regression. RESULTS: A total of 61 patients were identified. FO evaluation localized the SOZ in 56 % of patients. Complications were encountered in 1.6 % of patients. Subsequent surgical resection was pursued by 49 % of patients, with 56 % becoming seizure free, and 67 % having favorable seizure outcomes at last follow-up. Multivariate analysis identified younger patients with a higher number of preoperative ASMs as more likely to undergo subsequent treatment, however, these features were not predictive features of SOZ localization, seizure freedom, or favorable seizure outcomes. In patients with bitemporal or cross-over onsets on scalp EEG, FO was able to identify the SOZ in 79 %, whereas in patients with discordant or unclear onset, the rates were 71 % and 45 %, respectively. CONCLUSION: In a contemporary cohort, FO electrode placement had a low complication rate and a high utility primarily in cases of unclear laterality of mesial temporal onsets or discordance between scalp EEG and other pre-FO investigation data in cases of suspected mesial temporal onsets.

Predictors of SOZ localization, subsequent surgical intervention, and seizure outcomes in iEEG.

OBJECTIVE: A third of the patients who undergo intracranial EEG (iEEG) for seizure-onset zone (SOZ) localization do not proceed to resective surgery for epilepsy, and over half of those who do continue to have seizures following treatment. To better identify candidates who are more likely to see benefits from undergoing iEEG, we investigated preoperative and iEEG peri-operative features associated with the localization of a putative SOZ, undergoing subsequent surgical treatment, and seizure outcomes. METHODS: We conducted a retrospective cohort study of consecutive patients who underwent iEEG from 2001 to 2022 at two institutions. Outcomes included SOZ identification, proceeding to surgical treatment (resection vs. neuromodulation), and subsequent seizure freedom. RESULTS: We identified 329 unique patients who were followed for a median of 3.9 (IQR:7) years, with a minimum of 2-year follow-up for seizure outcomes analyses. Multivariate analysis identified lateralized and lobar localization on scalp EEG (OR 3.8, p = 0.001) to be associated with SOZ localization. Patients with unilateral localization on scalp EEG (OR 3.0, p = 0.003), unilateral preimplantation hypothesis (OR 3.1, p = 0.001), and lesional preoperative MRI (OR 2.1, p = 0.033) were more likely to undergo resection than neuromodulation. Similarly, a unilateral pre-implantation hypothesis (OR 2.6, p < 0.001) favored seizure freedom, whereas prior neuromodulation (OR 0.3, p = 0.013) decreased the odds. Larger number of preoperative anti-seizure medications (ASMs) did not influence seizure freedom rates but did decrease favorable (Engel I, II) seizure outcomes (OR 0.7, p = 0.026). INTERPRETATION: Non-invasive localization data prior to iEEG are associated with subsequent resection and seizure freedom, independent of iEEG localization. Factors predictive of SOZ localization are not necessarily predictive of post-operative seizure freedom.

Magnetic resonance-guided focused ultrasound thalamotomy for essential tremor patients with low skull density ratio: a case-matched analysis.

Introduction: Skull density ratio (SDR) is the ratio between the mean Hounsfield units of marrow and cortical bone, impacting energy transmission through the skull. Low SDR has been used as an exclusion criterion in major trials of magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy for medication-refractory essential tremor (ET). However, some studies have suggested that patients with low SDR can safely undergo MRgFUS with favorable outcomes. In this case-matched study, we aim to compare the characteristics, sonication parameters, lesion sizes, and clinical outcomes of patients with low SDR vs. patients with high SDR who underwent unilateral MRgFUS thalamotomy for medication-refractory ET. Methods: Between March 2016 and April 2023, all patients (n = 270) who underwent unilateral MRgFUS thalamotomy for medication-refractory ET at a single institution were classified as low SDR (<0.40) and high SDR (≥0.40). All clinical and radiological data was prospectively collected and retrospectively analyzed using non-case-matched and 1:1 case-matched methodology. Results: Thirty-one patients had low SDR, and 239 patients had high SDR. Fifty-six patients (28 in each cohort) were included in 1:1 case-matched analysis. There were no significant differences in baseline characteristics between the two groups in both non-case-matched and 1:1 case-matched analyses. In both analyses, compared to patients with high SDR, patients with low SDR required a significantly higher maximum sonication power, energy, and duration, and reached a lower maximum temperature with smaller lesion volumes. In the non-case-matched and case-matched analyses, low SDR patients did not have significantly less tremor control at any postoperative timepoints. However, there was a higher chance of procedure failure in the low SDR group with three patients not obtaining an appropriately sized lesion. In both analyses, imbalance was observed more often in high SDR patients on postoperative day 1 and month 3. Discussion: ET patients with SDR <0.40 can be safely and effectively treated with MRgFUS, though there may be higher rates of treatment failure and intraoperative discomfort.

Surgical management of status epilepticus: A systematic review.

Status Epilepticus (SE), unresponsive to medical management, is associated with high morbidity and mortality. Surgical management is typically considered in these refractory cases. The best surgical approach for affected patients remains unclear; however, given the lack of controlled trials exploring the role of surgery. We performed a systematic review according to PRIMSA guidelines, including case reports and series describing surgical interventions for patients in SE. Cases (157 patients, median age 12.9 years) were followed for a median of 12 months. Patients were in SE for a median of 21 days before undergoing procedures including: focal resection (36.9%), functional hemispherectomy (21%), lobar resection (12.7%), vagus nerve stimulation (VNS) (12.7%), deep brain stimulation (DBS) (6.4%), multiple subpial transection (MST) (3.8%), responsive neurostimulation (RNS) (1.9%), and cortical stimulator placement (1.27%), with 24 patients undergoing multiple procedures. Multiple SE semiologies were identified. 47.8% of patients had focal seizures, and 65% of patients had focal structural abnormalities on MRI. SE persisted for 36.8 ± 47.7 days prior to surgical intervention. SE terminated following surgery in 81.5%, terminated with additional adjuncts in 10.2%, continued in 1.9%, and was not specified in 6.4% of patients. Long-term seizure outcomes were favorable, with the majority improved and 51% seizure-free. Eight patients passed away in follow-up, of which three were in SE. Seizures emerging from one hemisphere were both more likely to immediately terminate (OR 4.7) and lead to long-term seizure-free status (OR 3.9) compared to nonunilateral seizures. No other predictors, including seizure focality, SE duration, or choice of surgical procedure, were predictors of SE termination. Surgical treatment of SE can be effective in terminating SE and leading to sustained seizure freedom, with many different procedures showing efficacy if matched appropriately with SE semiology and etiology. PLAIN LANGUAGE SUMMARY: Patients with persistent seizures (Status Epilepticus) that do not stop following medications can be treated effectively with surgery. Here, we systematically review the entirety of existing literature on surgery for treating status epilepticus to better identify how and when surgery is used and what patients do after surgery.

Comparative effectiveness of stereotactic, subdural, or hybrid intracranial EEG monitoring in epilepsy surgery.

OBJECTIVE: Surgical intervention can be curative or palliative for drug-resistant focal epilepsy. However, if the seizure onset zone (SOZ) cannot be adequately localized via noninvasive tests, intracranial EEG (iEEG) recordings are often carried out to develop surgical plans in appropriate candidates. Stereotactic EEG (SEEG), subdural EEG (SDE), and SDE with depth electrodes (hybrid) are major tools used for investigation, but there is no class 1 or 2 evidence comparing the effectiveness of these modalities. METHODS: The authors identified an institutional cohort of patients who underwent iEEG monitoring between 2001 and 2022. Demographic data, preoperative clinical features, iEEG intervention, and follow-up data were identified. Primary study endpoints included the following: 1) likelihood of SOZ localization; 2) likelihood of surgical treatment after iEEG; 3) seizure outcomes; and 4) complications. RESULTS: A total of 329 patients were identified (176 in the SEEG, 60 in the SDE, and 93 in the hybrid cohort) who were followed for a median of 5.4 (IQR 6.8) years. Baseline characteristics, including demographics, mean age at epilepsy diagnosis, mean age at iEEG investigation, number of preoperative antiseizure medications, and preoperative seizure frequency, were not statistically different across the 3 cohorts. Patients in the SEEG cohort were more likely to have their SOZ localized than were the patients in the SDE group (OR 2.3) and were less likely to undergo subsequent resection (OR 0.3) or to have complications (OR 0.4), although there was no statistical difference with respect to likelihood of undergoing any subsequent neurosurgical treatment, or with respect to favorable seizure outcomes. Patients in the hybrid cohort were more likely to have SOZ localized than were patients in the SDE group (OR 3.1), but were more likely to undergo resection (OR 4.9) or any neurosurgical treatment (OR 2.5) compared to patients in the SEEG group. Patients in the hybrid cohort had better seizure outcomes compared to the SDE (OR 2.3) but not to the SEEG group. CONCLUSIONS: Patients in the SEEG group were more likely to have their SOZ localized and patients in the SDE group were more likely to undergo resection, but they did not differ with respect to seizure outcomes.

Longitudinal MR imaging after unilateral MR-guided focused ultrasound thalamotomy: clinical and radiological correlation.

Introduction: Magnetic-resonance-guided focused ultrasound (MRgFUS) thalamotomy uses multiple converging high-energy ultrasonic beams to produce thermal lesions in the thalamus. Early postoperative MR imaging demonstrates the location and extent of the lesion, but there is no consensus on the utility or frequency of postoperative imaging. We aimed to evaluate the evolution of MRgFUS lesions and describe the incidence, predictors, and clinical effects of lesion persistence in a large patient cohort. Methods: A total of 215 unilateral MRgFUS thalamotomy procedures for essential tremor (ET) by a single surgeon were retrospectively analyzed. All patients had MR imaging 1 day postoperatively; 106 had imaging at 3 months and 32 had imaging at 1 year. Thin cut (2 mm) axial and coronal T2-weighted MRIs at these timepoints were analyzed visually on a binary scale for lesion presence and when visible, lesion volumes were measured. SWI and DWI sequences were also analyzed when available. Clinical outcomes including tremor scores and side effects were recorded at these same time points. We analyzed if patient characteristics (age, skull density ratio), preoperative tremor score, and sonication parameters influenced lesion evolution and if imaging characteristics correlated with clinical outcomes. Results: Visible lesions were present in all patients 1 day post- MRgFUS and measured 307.4 ± 128.7 mm3. At 3 months, residual lesions (excluding patients where lesions were not visible) were 83.6% smaller and detectable in only 54.7% of patients (n = 58). At 1 year, residual lesions were detected in 50.0% of patients (n = 16) and were 90.7% smaller than 24 h and 46.5% smaller than 3 months. Lesions were more frequently visible on SWI (100%, n = 17), DWI (n = 38, 97.4%) and ADC (n = 36, 92.3%). At 3 months, fewer treatment sonications, higher maximum power, and greater distance between individual sonications led to larger lesion volumes. Volume at 24 h did not predict if a lesion was visible later. Lesion visibility at 3 months predicted sensory side effects but was not correlated with tremor outcomes. Discussion: Overall, lesions are visible on T2-weighted MRI in about half of patients at both 3 months and 1 year post-MRgFUS thalamotomy. Certain sonication parameters significantly predicted persistent volume, but residual lesions did not correlate with tremor outcomes.

Focused Ultrasound Thalamotomy for Tremor in Parkinson's Disease: Outcomes in a Large, Prospective Cohort.

BACKGROUND: Magnetic resonance guided focused ultrasound (MRgFUS) is United States Food and Drug Administration approved for the treatment of tremor-dominant Parkinson's disease (TdPD), but only limited studies have been described in practice. OBJECTIVES: To report the largest prospective experience of unilateral MRgFUS thalamotomy for the treatment of medically refractory TdPD. METHODS: Clinical outcomes of 48 patients with medically refractory TdPD who underwent MRgFUS thalamotomy were evaluated. Tremor outcomes were assessed using the Fahn-Tolosa-Marin scale and adverse effects were categorized using a structured questionnaire and clinical exam at 1 month (n = 44), 3 months (n = 34), 1 year (n = 22), 2 years (n = 5), and 3 years (n = 2). Patients underwent magnetic resonance imaging <24 hours post-procedure. RESULTS: Significant tremor control persisted at all follow-ups (P < 0.001). All side effects were mild. At 3 months, these included gait imbalance (38.24%), sensory deficits (26.47%), motor weakness (17.65%), dysgeusia (5.88%), and dysarthria (5.88%), with some persisting at 1 year. CONCLUSIONS: MRgFUS thalamotomy is an effective treatment for sustained tremor control in patients with TdPD. © 2023 International Parkinson and Movement Disorder Society.

Deep Brain Stimulation Lead Localization Variability Comparing Intraoperative MRI Versus Postoperative Computed Tomography.

BACKGROUND AND OBJECTIVES: Commercially available lead localization software for deep brain stimulation (DBS) often relies on postoperative computed tomography (CT) scans to define electrode positions. When cases are performed with intraoperative MRI, another imaging set exists with which to perform these localizations. To compare DBS localization error between postoperative CT scans and intraoperative MRI. METHODS: A retrospective cohort of patients who underwent MRI-guided placement of DBS electrodes using the ClearPoint platform was identified. Using Brainlab Elements, postoperative CT scans were coregistered to intraoperative magnetic resonance images visualizing the ClearPoint guidance sheaths and ceramic stylets. DBS electrodes were identified in CT scans using Brainlab's lead localization tool. Trajectory and vector errors were quantified between scans for each lead in each patient. RESULTS: Eighty patients with a total of 157 implanted DBS electrodes were included. We observed mean trajectory and vector errors of 0.78 ± 0.44 mm (range 0.1-2.0 mm) and 1.57 ± 0.79 mm (range 0.2-4.2 mm), respectively, between postoperative CT and intraoperative MRI. There were 7 patients with CT scans collected at multiple time points. Trajectory error increased by 0.15 ± 0.42 mm ( P = .31), and vector error increased by 0.22 ± 0.53 mm ( P = .13) in the later scans. Across all scans, there was no significant association between trajectory ( P = .053) or vector ( P = .98) error and the date of CT acquisition. DBS electrodes targeting the subthalamic nucleus had significantly greater trajectory errors ( P = .02) than those targeting the globus pallidus pars internus nucleus. CONCLUSION: Commercially available software produced largely concordant lead localizations when comparing intraoperative MRIs with postoperative CT scans, with trajectory errors on average <1 mm. CT scans tend to be more comparable with intraoperative MRI in the immediate postoperative period, with increased time intervals associated with a greater magnitude of error between modalities.

Publication Rates and Characteristics of Clinical Trials in Deep Brain and Responsive Neurostimulation.

INTRODUCTION: Prompt dissemination of clinical trial results is essential for ensuring the safety and efficacy of intracranial neurostimulation treatments, including deep brain stimulation (DBS) and responsive neurostimulation (RNS). However, the frequency and completeness of results publication, and reasons for reporting delays, are unknown. Moreover, the patient populations, targeted anatomical locations, and stimulation parameters should be clearly reported for both reproducibility and to identify lacunae in trial design. Here, we examine DBS and RNS trials from 1997 to 2022, chart their characteristics, and examine rates and predictors of results reporting. METHODS: Trials were identified using ClinicalTrials.gov. Associated publications were identified using ClinicalTrials.gov and PubMed.gov. Pearson's χ2 tests were used to assess differences in trial characteristics between published and unpublished trials. RESULTS: Across 449 trials, representing a cumulative cohort of 42,769 patient interventions, there were 37 therapeutic indications and 44 stimulation targets. The most common indication and target were Parkinson's disease (40.55%) and the subthalamic nucleus (35.88%), respectively. Only 0.89% of trials were in pediatric patients (11.58% were mixed pediatric and adult). Explored targets represented 75% of potential basal ganglia targets but only 29% of potential thalamic targets. Allowing a 1-year grace period after trial completion, 34/169 (20.12%) had results reported on ClinicalTrials.gov, and 107/169 (63.31%) were published. ∼80% of published trials included details about stimulation parameters used. Published and unpublished trials did not significantly differ by trial characteristics. CONCLUSION: We highlight key knowledge and performance gaps in DBS and RNS trial research. Over one-third of trials remain unpublished >1 year after completion; pediatric trials are scarce; most of the thalamus remains unexplored; about one-in-five trials fail to report stimulation parameters; and movement disorders comprise the most studied indications.

Initial case series of a novel sensing deep brain stimulation device in drug-resistant epilepsy and consistent identification of alpha/beta oscillatory activity: A feasibility study.

OBJECTIVE: Here, we report a retrospective, single-center experience with a novel deep brain stimulation (DBS) device capable of chronic local field potential (LFP) recording in drug-resistant epilepsy (DRE) and explore potential electrophysiological biomarkers that may aid DBS programming and outcome tracking. METHODS: Five patients with DRE underwent thalamic DBS, targeting either the bilateral anterior (n = 3) or centromedian (n = 2) nuclei. Postoperative electrode lead localizations were visualized in Lead-DBS software. Local field potentials recorded over 12-18 months were tracked, and changes in power were associated with patient events, medication changes, and stimulation. We utilized a combination of lead localization, in-clinic broadband LFP recordings, real-time LFP response to stimulation, and chronic recordings to guide DBS programming. RESULTS: Four patients (80%) experienced a >50% reduction in seizure frequency, whereas one patient had no significant reduction. Peaks in the alpha and/or beta frequency range were observed in the thalamic LFPs of each patient. Stimulation suppressed these LFP peaks in a dose-dependent manner. Chronic timeline data identified changes in LFP amplitude associated with stimulation, seizure occurrences, and medication changes. We also noticed a circadian pattern of LFP amplitudes in all patients. Button-presses during seizure events via a mobile application served as a digital seizure diary and were associated with elevations in LFP power. SIGNIFICANCE: We describe an initial cohort of patients with DRE utilizing a novel sensing DBS device to characterize potential LFP biomarkers of epilepsy that may be associated with seizure control after DBS in DRE. We also present a new workflow utilizing the Percept device that may optimize DBS programming using real-time and chronic LFP recording.

The effects of low and normal dose ice slurry ingestion on endurance capacity and intestinal epithelial injury in the heat.

OBJECTIVES: Compare the effects of ice slurry ingestion at low and normal doses on endurance capacity and exertional heat stress-induced gastrointestinal perturbations. DESIGN: Randomised, cross-over design. METHODS: Twelve physically active males completed four treadmill running trials, ingesting ice slurry (ICE) or ambient drink (AMB) at 2 g·kg-1 (Normal; N) or 1 g·kg-1 (Low; L) doses every 15-min during exercise and 8 g·kg-1 (N) or 4 g·kg-1 (L) pre- and post-exercise. Pre-, during and post-exercise serum intestinal fatty-acid binding protein ([I-FABP]) and lipopolysaccharide ([LPS]) concentrations were determined. RESULTS: Pre-exercise gastrointestinal temperature (Tgi) was lower in L + ICE than L + AMB (p < 0.05), N + ICE than N + AMB (p < 0.001) and N + ICE than L + ICE (p < 0.001). Higher rate of Tgi rise (p < 0.05) and lower estimated sweat rate (p < 0.001) were observed in N + ICE than N + AMB. Rate of Tgi rise was similar at low dose (p = 0.113) despite a lower estimated sweat rate in L + ICE than L+AMB (p < 0.01). Time-to-exhaustion was longer in L + ICE than L + AMB (p < 0.05), but similar between N + ICE and N + AMB (p = 0.142) and L + ICE and N + ICE (p = 0.766). [I-FABP] and [LPS] were similar (p > 0.05). CONCLUSIONS: L + ICE elicited a lower heat dissipation compensatory effect with similar endurance capacity as N + ICE. Ice slurry conferred no protection against exertional heat stress-induced gastrointestinal perturbations.

Stereoelectroencephalography followed by combined electrode removal and MRI-guided laser interstitial thermal therapy or open resection: a single-center series in pediatric patients with medically refractory epilepsy.

OBJECTIVE: Stereoelectroencephalography (SEEG) and MRI-guided laser interstitial thermal therapy (MRgLITT) have emerged as safe, effective, and less invasive alternatives to subdural grid placement and open resection, respectively, for the localization and treatment of medically refractory epilepsy (MRE) in children. Reported pediatric experience combining these complementary techniques is limited, with traditional workflows separating electrode removal and ablation/resection. The authors describe the largest reported series of pediatric epilepsy patients who underwent MRgLITT following SEEG contrasted with a cohort that underwent craniotomy following SEEG, combining ablation/resection with electrode explantation as standard practice. METHODS: The medical records of all patients with MRE who had undergone SEEG followed by MRgLITT or open resection/disconnection at Boston Children's Hospital between November 2015 and December 2020 were retrospectively reviewed. Primary outcome variables included surgical complication rates, length of hospital stay following treatment, and Engel classification at the last follow-up. RESULTS: Of 74 SEEG patients, 27 (median age 12.1 years, 63% female) underwent MRgLITT and 47 (median age 12.1 years, 49% female) underwent craniotomy. Seventy patients (95%) underwent SEEG followed by combined electrode removal and treatment. Eight MRgLITT cases (30%) and no open cases targeted the insula (p < 0.001). Complication rates did not differ, although trends toward more subdural/epidural hematomas, infarcts, and permanent unanticipated neurological deficits were evident following craniotomy, whereas a trend toward more temporary unanticipated neurological deficits was seen following MRgLITT. The median duration of hospitalization after treatment was 3 and 5 days for MRgLITT and open cases, respectively (p = 0.078). Seizure outcomes were similar between the cohorts, with 74% of MRgLITT and craniotomy patients attaining Engel class I or II outcomes (p = 0.386) at the last follow-up (median 1.1 and 1.9 years, respectively). CONCLUSIONS: MRgLITT and open resection following SEEG can both effectively treat MRE in pediatric patients and generally can be performed in a two-surgery workflow during a single hospitalization. In appropriately selected patients, MRgLITT tended to be associated with shorter hospitalizations and fewer complications following treatment and may be best suited for focal deep-seated targets associated with relatively challenging open surgical approaches.

Focused Ultrasound Thalamotomy: Correlation of Postoperative Imaging with Neuropathological Findings.

Magnetic resonance-guided high-intensity focused ultrasound (MRgFUS) is a rapidly developing technique used for tremor relief in tremor-predominant Parkinson's disease (PD) and essential tremor that has demonstrated successful results. Here, we describe the neuropathological findings in a woman who died from a fall 10 days after successful MRgFUS for tremor-predominant PD. Histological analysis demonstrates the characteristic early postoperative MRI findings including 3 distinct zones on T2-weighted imaging: (1) a hypointense core, (2) a hyperintense region with hypointense rim, and (3) a slightly hyperintense, poorly marginated surrounding area. Histopathological analyses also demonstrate the suspected cellular processes composing each of these regions including central hemorrhagic necrosis with surrounding cytotoxic edema and a rim of mostly unaffected vasogenic edema with some reactive and reparative processes. Overall, this case demonstrates the correlation of postoperative imaging findings with the subacute neuropathological findings after MRgFUS for PD.

Transcranial MR-Guided Focused Ultrasound and Hyperostosis Calvariae Diffusa: Case Report and Systematic Review of the Literature.

We describe a 74-year-old male with intractable essential tremor (ET) and hyperostosis calvariae diffusa who was unsuccessfully treated with magnetic resonance-guided focused ultrasound (MRgFUS). A computed tomography performed prior to the procedure demonstrated a skull density ratio (SDR) of 0.37 and tricortical hyperostosis calvariae diffusa. No lesion was evident on post-MRgFUS MRI, and no improvement in the patient's hand tremor was noted clinically. We systematically reviewed the literature to understand outcomes for those patients with hyperostosis who have undergone MRgFUS. A comprehensive literature search using the PubMed, Cochrane, and Google Scholar databases identified 3 ET patients with hyperostosis who failed treatment with MRgFUS. Clinical findings, skull characteristics, treatment parameters, and outcomes were summarized, demonstrating different patterns/degrees of bicortical hyperostosis and variable SDRs (i.e., from 0.38 to ≥0.45). Although we have successfully treated patients with bicortical hyperostosis frontalis interna (n = 50), tricortical hyperostosis calvariae diffusa appears to be a contraindication for MRgFUS despite acceptable SDRs.

Cerebrovascular injuries in traumatic brain injury.

Traumatic brain injury is a complex and highly heterogeneous disease due to the host of concomitant injuries that may accompany the initial insult. Due to the dynamic interplay between the injuries that may arise, the management of these injuries is challenging. In a small subset of patients with traumatic brain injury, cerebral vascular injury may occur, which presents its own diagnostic and therapeutic challenges. These vascular injuries often present in a delayed fashion, thereby going unnoticed by clinicians. Early recognition and treatment of these injuries is crucial, given their high morbidity and mortality. Through a critical review of the literature, we present the spectrum of cerebrovascular injuries that may occur with traumatic brain injury and discuss classification systems that are used to stratify cerebrovascular injury. We then focus on the diagnosis of cerebral vascular injury using different neuroimaging modalities. Lastly, we explore the treatment of these injuries ranging from antiplatelet therapies to endovascular and open vascular procedures. By highlighting the pitfalls and challenges of this complex disease, we hope to provide clinicians with the framework to recognize and treat vascular injuries that are seen in patients with traumatic brain injury.

Intraoperative Ultrasound in Spinal Surgery.

Since the 1980s, there have been several reports for the use of intraoperative ultrasound as a useful adjunct in spinal surgery. However, with the advent of newer cutting-edge imaging modalities, the use of intraoperative ultrasound in spine surgery has largely fallen out of favor. Despite this, intraoperative ultrasound continues to provide several advantages over other intraoperative techniques such as magnetic resonance imaging and computed tomography including being more cost-effective, efficient, and easy to operate and interpret. Additionally, it remains the only method for the real-time visualization of soft tissue and pathologies. This paper focuses on the advantages of using intraoperative ultrasound, especially in cases of intradural lesions and lesions ventral to the thecal sac when approaching posteriorly.

Spinal osteomyelitis and epidural abscess caused by ureterovertebral fistula: A case report.

Background: Ureteral fistulas are abnormal connections between the ureters and other organs. Maintaining a high index of suspicion is important because they can precipitate dangerous complications such as sepsis and renal failure. Connections to a vertebral body have only been documented in the setting of trauma. Here, we present a 67-year-old female with a ureterovertebral fistula extending into the L3 vertebral body. Case Description: A 67-year-old female with a history of endometrial adenocarcinoma underwent surgery and radiation therapy complicated by a right ureteral obstruction requiring stent placement. Five months later, she developed back pain and MR-documented L2-L4 level osteomyelitis/discitis with a psoas phlegmon/abscess, which required drainage. A fistula was later identified between the right ureter and the psoas phlegmon. Despite percutaneous nephrostomy placement and aggressive IV antibiotic treatment, she was readmitted for persistent signs of infection over the next few months during which time she was repeatedly and unsuccessfully treated with multiple antibiotics. Sixteen months following her original stent placement, she developed right leg weakness and urinary incontinence attributed to the MR-documented ureteropsoas fistula extending into the L3 vertebral body. Following a nephrectomy with ureteral ligation, an L3 anterior corpectomy with interbody fusion for discitis at both L2-L3 and L3-L4, and an L1-L5 posterolateral fusion, she was discharged to a rehabilitation center. Conclusion: In patients with recurrent sepsis, osteomyelitis/discitis, or psoas abscess of unknown origin or who have a significant history (e.g., pelvic malignancy, radiation, and instrumentation), it is important to consider urodynamic testing to look for a ureteral leak or fistula.

Parsonage-Turner syndrome following COVID-19 vaccination and review of the literature.

Background: Parsonage-Turner syndrome (PTS) is a rare brachial plexopathy characterized by self-limiting shoulder girdle and upper arm pain followed by the upper extremity weakness and sensory changes. While the etiology is not well-understood, the most common cause of PTS is thought to be postviral. There are at least nine reports, to the best of our knowledge, of PTS associated with COVID-19 infection and nine reports associated with COVID-19 vaccination. Case Description: Here, we present a case of PTS after COVID-19 vaccination in a 64-year-old male and a review of the current literature. Conclusion: PTS can occur post-COVID-19 vaccination and should be on the differential diagnosis when patient continues to experience shoulder pain and develops weakness or sensory changes in the extremity.