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Purpose Adjuvant radiation therapy for atypical meningiomas (AMs) aids in local control following surgery and salvage after recurrence. The role of fractionated stereotactic radiosurgery (FSRT) in this population remains an area of active study with many unanswered clinical questions. This single-institution retrospective study evaluates the local control, marginal control, and toxicity of FSRT in treating AM. Methods Between 2009 and 2022, 39 patients with WHO grade 2 AM underwent FSRT via marginless, frameless volumetric-modulated arc therapy (VMAT) at doses of 27.5-30 Gy in five fractions. Local recurrence was defined as an increase of 20% in the greatest cross-sectional diameter on MRI or CT, following RECIST criteria. Cavity and marginal recurrences were defined as any new lesion outside the prescription volume but within the resection cavity or within 2 cm of the resection cavity, respectively. High-grade toxicity was defined per Common Terminology Criteria for Adverse Events (CTCAE) v5. Resection for radionecrosis with viable residual tumor was considered a local failure. Results Twenty-six AMs were treated post-subtotal resection (STR), 16 post-gross total resection (GTR) with recurrence, and five treated definitively. Patient characteristics included a mean age of 54 years, 20 (51%) male patients, and 31 (79%) patients with ECOG 0-1. The three-year local control rate was 84.0%. Larger tumors were more likely to fail locally (p > 0.001). Two (5%) patients experienced high-grade toxicity necessitating resection. The three-year marginal control rate was 92.3%, and recurrent tumors post-GTR failed marginally more often compared to those treated after STR (p = 0.009). One (4%) tumor treated after STR failed marginally, while four (33%) tumors treated after GTR recurrence failed marginally. The three-year control rate of the unirradiated cavity was 88%. Conclusion The rate of high-grade toxicity in AM patients receiving FSRT was low. Local control appeared comparable to historical rates, which may suggest the potential need for dose escalation with longer-term follow-up. Recurrent tumors were more prone to marginal failures. Further investigation is needed to determine which patients may benefit from whole-cavity treatment, additional CTV margin, or prolonged fractionated dose schedules. Newer imaging studies, including DOTATATE PET, should be explored to assess whether improvements in targeting accuracy can enhance outcomes., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2025, Travis et al.) more...

Objective: We aimed to compare outcomes including seizure-free status at the last follow-up in adult patients with medically refractory focal epilepsy identified as lesional vs. non-lesional based on their magnetic resonance imaging (MRI) findings who underwent invasive evaluation followed by subsequent resection or thermal ablation (LiTT)., Methods: We identified 88 adult patients who underwent intracranial monitoring between 2014 and 2021. Of those, 40 received resection or LiTT, and they were dichotomized based on MRI findings, as lesional ( N  = 28) and non-lesional ( N  = 12). Patient demographics, seizure characteristics, non-invasive interventions, intracranial monitoring, and surgical variables were compared between the groups. Postsurgical seizure outcome at the last follow-up was rated according to the Engel classification, and postoperative seizure freedom was determined by Kaplan-Meyer survival analysis. Statistical analyses employed Fisher's exact test to compare categorical variables, while a t-test was used for continuous variables., Results: There were no differences in baseline characteristics between groups except for more often noted PET abnormality in the lesional group ( p  = 0.0003). 64% of the lesional group and 57% of the non-lesional group received surgical resection or LiTT ( p  = 0.78). At the last follow-up, 78.5% of the patients with lesional MRI findings achieved Engel I outcomes compared to 66.7% of non-lesional patients ( p  = 0.45). Kaplan-Meier curves did not show a significant difference in seizure-free duration between both groups after surgical intervention ( p  = 0.49)., Significance: In our sample, the absence of lesion on brain MRI was not associated with worse seizure outcomes in adult patients who underwent invasive intracranial monitoring followed by resection or thermal ablation. more...

Background: Postoperative pseudomeningocele (PMC) and cerebrospinal fluid (CSF) leak are common complications following posterior fossa and posterolateral skull base surgeries. We sought to 1) determine the rate of CSF-related complications and 2) develop a perioperative model and risk score to identify the highest risk patients for these events., Methods: We performed a retrospective cohort of 450 patients undergoing posterior fossa and posterolateral skull base procedures from 2016 to 2020. Logistic regressions were performed for predictor selection for 3 prespecified models: 1) a priori variables, 2) predictors selected by large effect sizes, and 3) predictors with P ≤ 0.100 on univariable analysis. A final model was created by elimination of nonsignificant predictors, and the integer-based postoperative CSF-related complications (POCC) clinical risk score was derived. Internal validation was done using 10-fold cross-validation and bootstrapping with uniform shrinkage., Results: A total of 115 patients (25.6%) developed PMC and/or CSF leakage. Age >55 years (odds ratio [OR], 0.560; 95% confidence interval [CI], 0.328-0.954), body mass index >30 kg/m 2 (OR, 1.88; 95% CI, 1.14-3.10), and postoperative CSF diversion (OR, 2.85; 95% CI, 1.64-5.00) were associated with CSF leak and PMC. Model 2 was the most predictive (cross-validated area under the receiver operating characteristic curve, 0.690). The final risk score was devised using age, body mass index class, dural repair technique, use of bone substitute, and duration of postoperative CSF diversion. The POCC score performed well (cross-validated area under the receiver operating characteristic curve, 0.761) and was highly specific (96.1%)., Conclusions: We created the first generalizable and predictive risk score to identify patients at risk of CSF-related complications. The POCC score could improve surveillance, inform doctor-patient discussions regarding the risks of surgery, and assist in perioperative management., (Copyright © 2023 Elsevier Inc. All rights reserved.) more...

Background and Objectives: There is wide variation in treatment planning strategy for central nervous system (CNS) stereotactic radiosurgery. We sought to understand what relationships exist between intratumor maximum dose and local control (LC) or CNS toxicity, and dosimetric effects of constraining hotspots on plan quality of multiple metastases volumetric modulated arc therapy radiosurgery plans., Methods: We captured brain metastases from 2015 to 2017 treated with single-isocenter volumetric modulated arc therapy radiosurgery. Included tumors received single-fraction stereotactic radiosurgery, had no previous surgery or radiation, and available follow-up imaging. Our criterion for local failure was 25% increase in tumor diameter on follow-up MRI or pathologic confirmation of tumor recurrence. We defined significant CNS toxicity as Radiation Therapy Oncology Group irreversible Grade 3 or higher. We performed univariate and multivariate analyses evaluating factors affecting LC. We examined 10 stereotactic radiosurgery plans with prescriptions of 18 Gy to all targets originally planned without constraints on the maximum dose within the tumor. We replanned each with a constraint of Dmax 120%. We compared V50%, mean brain dose, and Dmax between plans., Results: Five hundred and thirty tumors in 116 patients were available for analysis. Median prescription dose was 18 Gy, and median prescription isodose line (IDL) was 73%. Kaplan-Meier estimate of 12-month LC only tumor volume (HR 1.43 [1.22-1.68] P < .001) was predictive of local failure on univariate analysis; prescription IDL and histology were not. In multivariate analysis, tumor volume impacted local failure (HR 1.43 [1.22-1.69] P < .001) but prescription IDL did not (HR 0.95 [0.86-1.05] P = .288). Only a single grade 3 and 2 grade 4 toxicities were observed; tumor volume was predictive of CNS toxicity (HR 1.58 [1.25-2.00]; P < .001), whereas prescription IDL was not (HR 1.01 [0.87-1.17] P = .940)., Conclusion: The prescription isodose line had no impact on local tumor control or CNS toxicity. Penalizing radiosurgery hotspots resulted in worse radiosurgery plans with poorer gradient. Limiting maximum dose in gross tumor causes increased collateral exposure to surrounding tissue and should be avoided., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Congress of Neurological Surgeons.) more...

Purpose: To commission and assess the clinical performance of a new commercial surface imaging (SI) system by analyzing intra-fraction motion from the initial cohort of patients treated with frameless stereotactic radiosurgery (fSRS)., Methods: The IDENTIFY TM SI system was commissioned for clinical use on an Edge (Varian Medical Systems, Palo Alto, CA) linear accelerator. All patients who received intracranial radiotherapy with HyperArc TM (Varian Medical Systems, Palo Alto, CA) were immobilized with the Encompass TM (Qfix, Avondale, PA) thermoplastic mask and monitored for intra-fraction motion with SI. IDENTIFY TM log files were correlated with trajectory log files to correlate treatment parameters with SI-reported offsets. IDENTIFY TM reported offsets were correlated with gantry and couch angles to assess system performance for obstructed and clear camera field of view. Data were stratified by race to evaluate performance differences due to skin tone., Results: All commissioning data were found to meet recommended tolerances. IDENTIFY TM was used to monitor intra-fraction motion on 1164 fractions from 386 patients. The median magnitude of translational SI reported offsets at the end of treatment was 0.27 mm. SI reported offsets were shown to increase when camera pods are blocked by the gantry with larger increases seen at non-zero couch angles. With camera obstruction, the median magnitude of the SI reported offset was 0.50 and 0.80 mm for White and Black patients, respectively., Conclusions: IDENTIFY TM performance during fSRS is comparable to other commercially available SI systems where offsets are shown to increase at non-zero couch angles and during camera pod blockage., (© 2023 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.) more...

BACKGROUND: Studies of continuous electroencephalography (EEG) suggest that seizures in individuals with focal-onset epilepsies preferentially occur during periods of heightened risk, typified by pathologic brain activities, termed pro-ictal states; however, the presence of (pathologic) pro-ictal states among a plethora of otherwise physiologic (e.g., sleep–wake cycle) states has not been established. METHODS: We studied a prospective, consecutive series of 15 patients with temporal lobe epilepsy who underwent limbic thalamic recordings in addition to routine (cortical) intracranial EEG for seizure localization. For each participant, pro-ictal (45 minutes before seizure onset) and interictal (4 hours removed from all seizures) EEG segments were divided into 10-minute, nonoverlapping windows, which were randomly distributed into training and validation cohorts in a 1:1 ratio. A deep neural classifier was applied to distinguish pro-ictal from interictal brain activities in a patient-specific fashion. RESULTS: We analyzed 1800 patient-hours of continuous thalamocortical EEG. Distinct pro-ictal states were detected in each participant. The median area under the receiver-operating characteristic curve of the classifier was 0.92 (interquartile range, 0.90–0.96). Pro-ictal states were distinguished at least 45 minutes before seizure onset in 13 of 15 participants; in 2 of 15 participants, they were distinguished up to 35 minutes prior. CONCLUSIONS: On the basis of thalamocortical EEG, pro-ictal states — pathologic brain activities during periods of heightened seizure risk — could be identified in patients with temporal lobe epilepsy and were detected, in our small sample, more than one half hour before seizure onset. more...

Seizure clusters are seizures that occur in rapid succession during periods of heightened seizure risk and are associated with substantial morbidity and sudden unexpected death in epilepsy. The objective of this feasibility study was to evaluate the performance of a novel seizure cluster forecasting algorithm. Chronic ambulatory electrocorticography recorded over an average of 38 months in 10 subjects with drug-resistant epilepsies was analyzed pseudoprospectively by dividing data into training (first 85%) and validation periods. For each subject, the probability of seizure clustering, derived from the Kolmogorov-Smirnov statistic using a novel algorithm, was forecasted in the validation period using individualized autoregressive models that were optimized from training data. The primary outcome of this study was the mean absolute scaled error (MASE) of 1-day horizon forecasts. From 10 subjects, 394 ± 142 (mean ± SD) electrocorticography-based seizure events were extracted for analysis, representing a span of 38 ± 27 months of recording. MASE across all subjects was .74 ± .09, .78 ± .09, and .83 ± .07 at .5-, 1-, and 2-day horizons. The feasibility study demonstrates that seizure clusters are quasiperiodic and can be forecasted to clinically meaningful horizons. Pending validation in larger cohorts, the forecasting approach described herein may herald chronotherapy during imminent heightened seizure vulnerability., (© 2022 International League Against Epilepsy.) more...