Faculty Bibliography

BACKGROUND:: Sports-related concussion commonly affects the visual pathways. Current sideline protocols test cognition and balance but do not include assessments of visual performance. We investigated how adding a vision-based test of rapid number naming could increase our ability to identify concussed athletes on the sideline at youth and collegiate levels. METHODS:: Participants in this prospective study included members of a youth ice hockey and lacrosse league and collegiate athletes from New York University and Long Island University. Athletes underwent preseason baseline assessments using: 1) the King-Devick (K-D) test, a <2-minute visual performance measure of rapid number naming, 2) the Standardized Assessment of Concussion (SAC), a test of cognition, and 3) a timed tandem gait test of balance. The SAC and timed tandem gait are components of the currently used Sport Concussion Assessment Tool, 3rd Edition (SCAT3 and Child-SCAT3). In the event of a concussion during the athletic season, injured athletes were retested on the sideline/rink-side. Nonconcussed athletes were also assessed as control participants under the same testing conditions. RESULTS:: Among 243 youth (mean age 11 +/- 3 years, range 5-17) and 89 collegiate athletes (age 20 +/- 1 years, range 18-23), baseline time scores for the K-D test were lower (better) with increasing participant age (P < 0.001, linear regression models). Among 12 athletes who sustained concussions during their athletic season, K-D scores worsened from baseline by an average of 5.2 seconds; improvement by 6.4 seconds was noted for the nonconcussed controls (n = 14). The vision-based K-D test showed the greatest capacity to distinguish concussed vs control athletes based on changes from preseason baseline to postinjury (receiver operating characteristic [ROC] curve areas from logistic regression models, accounting for age = 0.92 for K-D, 0.87 for timed tandem gait, and 0.68 for SAC; P = 0.0004 for comparison of ROC curve areas). CONCLUSIONS:: Adding a vision-based performance measure to cognitive and balance testing enhances the detection capabilities of current sideline concussion assessment. This observation in patients with mild traumatic brain injury reflects the common involvement and widespread distribution of brain pathways dedicated to vision.

BACKGROUND: Concussion, particularly in relation to sports and combat activities, is increasingly recognized as a potential cause of both short- and long-term neurologic sequelae. This review will focus on the neuro-ophthalmologic findings associated with concussion, the current tests for concussion, and the potential for visual performance measures to improve our detection and assessment of concussions. EVIDENCE ACQUISITION: A PubMed search using the specific key words "concussion," "mild traumatic brain injury," "neuro-ophthalmological findings," and "diagnostic and management tests" was performed. An emphasis was placed on articles published during the past 5 years, but additional articles referenced within recent publications were obtained. RESULTS: Concussion is frequently associated with abnormalities of saccades, pursuit eye movements, convergence, accommodation, and the vestibular-ocular reflex. Current sideline testing for athletes includes the Sports Concussion Assessment Tool, Third Edition (SCAT3) incorporates cognitive and balance testing. The King-Devick (K-D) test is a rapid visual performance measures that can be used on sidelines by nonmedical personnel, including parents of youth athletes. The K-D test complements components of the SCAT3 and improves the detection of concussions. Other vision-based tools for diagnosing and for managing concussion include eye movement tracking devices, pupillary assessment, computerized testing, imaging modalities, and eletrophysiologic testing. Many of the imaging modalities and electrophysiological studies have been combined with vision-based tests. CONCLUSIONS: Concusssion is associated with many neuro-ophthalmologic signs and symptoms. Visual performance measures enhance the detection and management of concussion, and future studies are under way to further incorporate vision-based testing into sideline diagnosis and long-term clinical assessments.

PURPOSE: Sports-related concussion has received increasing attention as a result of neurologic sequelae seen among athletes, highlighting the need for a validated, rapid screening tool. The King-Devick (K-D) test requires vision, eye movements, language function and attention in order to perform and has been proposed as a promising tool for assessment of concussion. We investigated the K-D test as a sideline screening tool in a collegiate cohort to determine the effect of concussion. METHODS: Athletes (n=127, mean age 19.6+/-1.2 years) from the Wheaton College football and men's and women's basketball teams underwent baseline K-D testing at pre-season physicals for the 2012-2013 season. K-D testing was administered immediately on the sidelines for football players with suspected head injury during regular games and changes compared to baseline were determined. Post-season testing was also performed to compare non-concussed athletes' test performance. RESULTS: Concussed athletes (n=11) displayed sideline K-D scores that were significantly higher (worse) than baseline (36.5+/-5.6s vs. 31.3+/-4.5s, p<0.005, Wilcoxon signed-rank test). Post-season testing demonstrated improvement of scores and was consistent with known learning effects (35.1+/-5.2s vs. 34.4+/-5.0s, p<0.05, Wilcoxon signed-rank test). Test-retest reliability was analyzed between baseline and post-season administrations of the K-D test resulting in high levels of test-retest reliability (intraclass correlation coefficient (ICC)=0.95 [95% Confidence Interval 0.85-1.05]). CONCLUSIONS: The data show worsening of K-D test scores following concussion further supporting utility of the K-D test as an objective, reliable and effective sideline visual screening tool to help identify athletes with concussion.