Baseline Visual Measures in High School Football Players With and Without Previous Concussion

Abstract

Visual impairments are common following sport-related concussion and may negatively affect athlete performance and safety if unresolved. PURPOSE: To examine differences in baseline visual assessment measures in high school football players with and without previous concussion. A secondary purpose was to examine the correlations between these asessments. METHODS: High school varsity football players (n=64, n=24 with concussion history) from a single high school (mean age=15.6±1.3 years) were enrolled in the study. Participants completed the following assessments prior to the start of the competitive football season: 1) three near-point of convergence (NPC) trials, 2) vision and sensory performance testing via the Senaptec Sensory Station, and 3) a demographic questionnaire. The independent variable was previous concussion history (with vs. without). Primary outcomes were average NPC across three trials (measured in centimeters) and the Senaptec Sensory Station scores for: visual clarity, contrast sensitivity, depth perception, near-far quickness, perception span, multiple object tracking, and hand-reaction time. Independent samples t-tests were used to examine differences in visual assessments between those with and without previous concussion. Pearson correlations examined relationships between all Senaptec Sensory Station and mean NPC measures. Alpha level was set to P < 0.05 a priori. RESULTS: Over half (62.5%) of those who reported a concussion history indicated that their most recent concussion was within the last year. There was no significant effect of concussion history on any of the visual assessment measures. There was a significant, but clinically insignificant correlation between mean NPC and binocular visual clarity (r=0.26; P=0.03). No other significant correlations among the visual assessment measures were identified (P < 0.05). CONCLUSION: High school football athletes, regardless of concussion history, exhibit similar baseline clinical and performance visual measures. Our data suggest that NPC and binocular visual clarity, while statistically correlated are clinically independent of one another and both worthy of evaluation in assessing concussion.