Correlation of Head Impact Exposures With Vestibulo-Ocular Assessments.

CONTEXT: Managing a concussion injury should involve the incorporation of a multifaceted approach, including a vision assessment. The frontoparietal circuits and subcortical nuclei are susceptible to trauma from a concussion injury, leading to dysfunction of the vestibulo-ocular system. Research investigating the effect of cumulative subconcussive impacts on neurological function is still in its infancy, but repetitive head impacts may result in vestibular system dysfunction. This dysfunction could create visual deficits, predisposing the individual to further head trauma.

OBJECTIVE

The purpose of this study was to investigate the cumulative effect of subconcussive impacts on minimum perception time, static visual acuity, gaze stability, and dynamic visual acuity scores.

DESIGN

Prospective cohort.

SETTING

Division I university.

PATIENTS: Thirty-three Division I men's lacrosse players (age = 19.52 [1.20] y).

INTERVENTION: Competitive lacrosse season.

MAIN OUTCOME MEASURES: At the beginning and end of the season, the players completed a vestibulo-ocular reflex assessment, using the InVision™ system by Neurocom® to assess perception, static acuity, gaze stability, and dynamic visual acuity. Score differentials were correlated with the head impact exposure data collected via instrumented helmets.

RESULTS

A significant correlation was found between change in perception scores and total number of head impacts (r = .54), and between changes in dynamic visual acuity loss scores on the rightside and maximum rotational acceleration (r = .36). No statistical differences were found between preseason and postseason vestibulo-ocular reflex variables.

CONCLUSIONS

Cumulative subconcussive impacts may negatively affect vestibulo-ocular reflex scores, resulting in decreased visual performance. This decrease in vestibulo-ocular function may place the athlete at risk of sustaining additional head impacts or other injuries.