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Background and Purpose: During a season of high school football, adolescents with actively developing brains experience a considerable number of head impacts. Our aim was to determine whether repetitive head impacts in the absence of a clinically diagnosed concussion during a season of high school football produce changes in cognitive performance or functional connectivity of the salience network and its central hub, the dorsal anterior cingulate cortex., Materials and Methods: Football players were instrumented with the Head Impact Telemetry System during all practices and games, and the helmet sensor data were used to compute a risk-weighted exposure metric (RWEcp), accounting for the cumulative risk during the season. Participants underwent MRI and a cognitive battery (ImPACT) before and shortly after the football season. A control group of noncontact/limited-contact-sport athletes was formed from 2 cohorts: one from the same school and protocol and another from a separate, nearly identical study., Results: Sixty-three football players and 34 control athletes were included in the cognitive performance analysis. Preseason, the control group scored significantly higher on the ImPACT Visual Motor ( P = .04) and Reaction Time composites ( P = .006). These differences increased postseason ( P = .003, P < .001, respectively). Additionally, the control group had significantly higher postseason scores on the Visual Memory composite ( P = .001). Compared with controls, football players showed significantly less improvement in the Verbal ( P = .04) and Visual Memory composites ( P = .01). A significantly greater percentage of contact athletes had lower-than-expected scores on the Verbal Memory (27% versus 6%), Visual Motor (21% versus 3%), and Reaction Time composites (24% versus 6%). Among football players, a higher RWEcp was significantly associated with greater increments in ImPACT Reaction Time ( P = .03) and Total Symptom Scores postseason ( P = .006). Fifty-seven football players and 13 control athletes were included in the imaging analyses. Postseason, football players showed significant decreases in interhemispheric connectivity of the dorsal anterior cingulate cortex ( P = .026) and within-network connectivity of the salience network ( P = .018). These decreases in dorsal anterior cingulate cortex interhemispheric connectivity and within-network connectivity of the salience network were significantly correlated with deteriorating ImPACT Total Symptom ( P = .03) and Verbal Memory scores ( P = .04)., Conclusions: Head impact exposure during a single season of high school football is negatively associated with cognitive performance and brain network connectivity. Future studies should further characterize these short-term effects and examine their relationship with long-term sequelae., (© 2024 by American Journal of Neuroradiology.)

Purpose: Previous research showed discrete neuropathological changes associated with rapid-onset dystonia-parkinsonism (RDP) in brains from patients with an ATP1A3 variant, specifically in areas that mediate motor function. The purpose of this study was to determine if magnetic resonance imaging methodologies could identify differences between RDP patients and variant-negative controls in areas of the brain that mediate motor function in order to provide biomarkers for future treatment or prevention trials., Methods: Magnetic resonance imaging voxel-based morphometry and arterial spin labeling were used to measure gray matter volume and cerebral blood flow, respectively, in cortical motor areas, basal ganglia, thalamus, and cerebellum, in RDP patients with ATP1A3 variants ( n = 19; mean age = 37 ± 14 years; 47% female) and variant-negative healthy controls ( n = 11; mean age = 34 ± 19 years; 36% female)., Results: We report age and sex-adjusted between group differences, with decreased cerebral blood flow among patients with ATP1A3 variants compared to variant-negative controls in the thalamus ( p = 0.005, Bonferroni alpha level < 0.007 adjusted for regions). There were no statistically significant between-group differences for measures of gray matter volume., Conclusions: There is reduced cerebral blood flow within brain regions in patients with ATP1A3 variants within the thalamus. Additionally, the lack of corresponding gray matter volume differences may suggest an underlying functional etiology rather than structural abnormality., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Whitlow, Atcheson, Snively, Cook, Kim, Haq, Sweadner, Ozelius and Brashear.)

OBJECTIVE The authors of this study found that, given the latency period required for arteriovenous malformation (AVM) obliteration after stereotactic radiosurgery (SRS), a study with limited follow-up cannot assess the benefit of SRS for unruptured AVMs. METHODS The authors reviewed their institutional experience with "ARUBA (A Randomized Trial of Unruptured Brain Arteriovenous Malformations)-eligible" AVMs treated with SRS between 1987 and 2016, with the primary outcome defined as stroke (ischemic or hemorrhagic) or death (AVM related or AVM unrelated). Patients with at least 3 years of follow-up in addition to those who experienced stroke or died during the latency period were included. Secondary outcome measures included obliteration rates, patients with new seizure disorders, and those with new focal deficits without stroke. RESULTS Of 233 patients included in this study, 32 had a stroke or died after SRS over the mean 8.4-year follow-up (14%). Utilizing the 10% stroke or death rate at a mean 2.8-year follow-up for untreated AVMs in ARUBA, the rate in the authors' study is significantly lower than that anticipated at the 8.4-year follow-up for an untreated cohort (14% vs 30%, p = 0.0003). Notwithstanding obliteration, in this study, annualized rates of hemorrhage and stroke or death after 3 years following SRS were 0.4% and 0.8%, respectively. The overall obliteration rate was 72%; new seizure disorders, temporary new focal deficits without stroke, and permanent new focal deficits without stroke occurred in 2% of patients each. CONCLUSIONS After a sensible follow-up period exceeding the latency period, there is a lower rate of stroke/death for patients with treated, unruptured AVMs with SRS than for patients with untreated AVMs.

Background: The rationale for treatment of dural arteriovenous fistulas (dAVFs) without cortical venous reflux is symptomatic resolution. Most studies of dAVF treatment, including those for stereotactic radiosurgery, have focused on angiographic obliteration instead of clinical symptomatic outcome., Methods: The authors evaluated their institutional experience with stereotactic radiosurgery for cerebral dAVFs without cortical venous reflux from 1991 to 2016, evaluating angiographic and clinical outcomes, focusing on the course of pulsatile tinnitus and/or ocular symptoms after treatment. They subsequently pooled their results with those from a systematic literature review., Results: Pooled outcomes data from 349 low-risk dAVF (120 patients with pulsatile tinnitus and 229 patients with ocular symptoms) were analyzed. Over a mean follow-up of 2.6 years, 77% of patients presenting with pulsatile tinnitus experienced resolution and an additional 21% had improvement, with an angiographic obliteration rate of 70.9%. Among 229 patients with ocular symptoms from carotid-cavernous dAVFs, improvement or resolution of symptoms occurred in 95% of those with chemosis, 90% of those with ophthalmoparesis, and 96% of those with proptosis. The angiographic obliteration rate was 76.2%. There were six permanent complications in 349 total treated low-risk dAVF (1.7%)., Conclusions: Rates of clinically significant symptomatic improvement/resolution of symptoms referable to "low-risk" dAVFs are even greater than their angiographic obliteration rate, an important factor in patient counseling and when considering the optimal treatment approach for these dAVFs., (Copyright © 2017 Elsevier Inc. All rights reserved.)