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Exploring the outcomes and experiences of Black and White athletes following a sport-related concussion: a retrospective cohort study

Aaron M. Yengo-Kahn, Jessica Wallace, Viviana Jimenez, Douglas J. Totten, Christopher M. Bonfield, and Scott L. Zuckerman


Young American athletes, at risk of sport-related concussion (SRC), represent many races; however, it is unknown how race may influence the experience and outcome of SRC. The authors’ objective was to compare White and Black athletes’ recovery and subjective experiences after SRC.


A retrospective study was performed using the Vanderbilt Sports Concussion registry. Self-reported White and Black young athletes (ages 12–23 years) who had been treated for SRC between 2012 and 2015 were included. Athletes with learning disabilities or psychiatric conditions were excluded. Data were collected by electronic medical record review and phone calls to athletes and parents or guardians. The primary outcomes were as follows: 1) days to symptom resolution (SR), 2) days to return to school, and changes in 3) any daily activity (binary) and 4) sport behavior (binary). Secondary outcomes were changes (more, unchanged, or less) in specific activities such as sleep, schoolwork, and television time, as well as equipment (binary) or playing style (more reckless, unchanged, or less reckless) and whether the athlete retired from sport. Descriptive analyses, multivariable Cox proportional hazards models, and logistic regression were performed.


The final cohort included 247 student-athletes (36 Black, 211 White). Black athletes were male (78% vs 58%) more often than White athletes, but both races were similar in age, sport, and medical/family histories. Black athletes more frequently had public insurance (33.3% vs 5.7%) and lived in areas with a low median income (41.2% vs 26.6%). After adjusting for age, sex, concussion history, insurance status, and zip code median income, Black athletes reached an asymptomatic status (HR 1.497, 95% CI 1.014–2.209, p = 0.042) and returned to school earlier (HR 1.522, 95% CI 1.020–2.270, p = 0.040). Black athletes were less likely to report a change in any daily activity than White athletes (OR 0.368, 95% CI 0.136–0.996, p = 0.049). Changes in sport behavior were comparable between the groups.


Racial differences appear to exist in the outcomes and experience of SRC for young athletes, as Black athletes reached SR and return to school sooner than White athletes. Race should be considered as an important social determinant in SRC treatment.

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A simple relationship between radiological arteriovenous malformation hemodynamics and clinical presentation: a prospective, blinded analysis of 31 cases

John S. Norris, Taufik A. Valiante, M. Christopher Wallace, Robert A. Willinsky, Walter J. Montanera, Karel G. terBrugge, and Michael Tymianski

Object. The authors sought to establish prospectively whether there is a simple relationship between radiological features of brain arteriovenous malformation (AVM) hemodynamics and a patient's clinical presentation.

Methods. Thirty-one consecutive patients with AVMs underwent cerebral angiography at 3.8 frames/second during each standardized injection of contrast material. Contrast dilution curves were derived from the image sequences by using regions of interest (ROIs) traced on arteries feeding and veins draining the AVM nidus. Angiographic parameters were then analyzed in a blinded fashion. These parameters included the times required to reach the peak contrast density, the contrast decay time, and fractions thereof, in the ROI for each vessel. The authors determined whether these parameters, the arteriovenous transit time, and/or AVM size were related to patients' presentation with hemorrhage (11 patients), seizure (11 patients), or other clinical symptoms (nine patients). Statistically significant results were found only in analyses of arterial phase times to reach peak contrast density. Analyses of venous parameters, AVM size, and nidus transit time showed trends but no statistical significance. Arterial filling with contrast material was significantly slower in patients presenting with hemorrhage (mean 50%, 80%, and 100% of time to peak ± standard error [SE] = 1.19 ± 0.13, 1.97 ± 0.18, and 3.04 ± 0.34 seconds, respectively) compared with patients presenting with seizures (mean 50%, 80%, and 100% of time to peak ± SE = 0.80 ± 0.12, 1.32 ± 0.18, and 1.95 ± 0.29 seconds, respectively) according to analysis of variance (p < 0.05) and post-hoc t-tests (p < 0.05) for each parameter. Patients who presented with other symptoms had intermediate arterial filling times.

Conclusions. These simple hemodynamic parameters, which can be obtained without added risk to the patient, may help identify a subset of individuals in whom AVMs pose a higher risk of future hemorrhage and who may therefore warrant more expeditious treatment.

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The validity of classification for the clinical presentation of intracranial dural arteriovenous fistulas

Mark A. Davies, Karel TerBrugge, Robert Willinsky, Terry Coyne, Jamshid Saleh, and M. Christopher Wallace

✓ A number of classification schemes for intracranial dural arteriovenous fistulas (AVFs) have been published that claim to predict which lesions will present in a benign or aggressive fashion based on radiological anatomy. We have tested the validity of two proposed classification schemes for the first time in a large single-institution study.

A series of 102 intracranial dural AVFs in 98 patients assessed at a single institution was analyzed. All patients were classified according to two grading scales: the more descriptive schema of Cognard, et al. (Cognard) and that recently proposed by Borden, et al. (Borden). According to the Borden classification, 55 patients were Type I, 18 Type II, and 29 Type III. Using the Cognard classification, 40 patients were Type I, 15 Type IIA, eight Type IIB, 10 Type IIA+B, 13 Type III, 12 Type IV, and four Type V.

Intracranial hemorrhage (ICH) or nonhemorrhagic neurological deficit was considered an aggressive presenting clinical feature. A total of 16 (16%) of 102 intracranial dural AVFs presented with hemorrhage. Eleven of these hemorrhages (69%) occurred in either anterior cranial fossa or tentorial lesions. When analyzed according to the Borden classification, none (0%) of 55 Type I intracranial dural AVFs, two (11%) of 18 Type II, and 14 (48%) of 29 Type III intracranial dural AVFs presented with hemorrhage (p < 0.0001). After exclusion of visual or cranial nerve deficits that were clearly related to cavernous sinus intracranial dural AVFs, nonhemorrhagic neurological deficits were a feature of presentation in one (2%) of 55 Type I, five (28%) of 18 Type II, and nine (31%) of 29 Type III patients (p < 0.0001). When combined, an aggressive clinical presentation (ICH or nonhemorrhagic neurological deficit) was seen most commonly in intracranial dural AVFs located in the tentorium (11 (79%) of 14) and the anterior cranial fossa (three (75%) of four), but this simply reflected the number of higher grade lesions in these locations. Aggressive clinical presentation strongly correlated with Borden types: one (2%) of 55 Type I, seven (39%) of 18 Type II, and 23 (79%) of 29 Type III patients (p < 0.0001). A similar correlation with aggressive presentation was seen with the Cognard classification: none (0%) of 40 Type I, one (7%) of 15 Type IIA, three (38%) of eight Type IIB, four (40%) of 10 Type IIA+B, nine (69%) of 13 Type III, 10 (83%) of 12 Type IV, and four (100%) of four Type V (p < 0.0001).

No location is immune from harboring lesions capable of an aggressive presentation. Location itself only raises the index of suspicion for dangerous venous anatomy in some intracranial dural AVFs. The configuration of venous anatomy as reflected by both the Cognard and Borden classifications strongly predicts intracranial dural AVFs that will present with ICH or nonhemorrhagic neurological deficit.

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Oral Presentations 2014 AANS Annual Scientific Meeting San Francisco, California • April 5–9, 2014

Published online June 1, 2015; DOI: 10.3171/2015.6.JNS.AANS2014abstracts