Altered Oculomotor and Vestibulo-ocular Function in Children and Adolescents Postconcussion

Abstract

Objective: To document (1) oculomotor (OM) and vestibulo-ocular (VO) function in children with concussion who were symptomatic at the time of assessment and to compare it with that in children with concussion who were clinically recovered (asymptomatic) and in children with no concussive injury, and (2) the extent to which OM and VO function relates to postconcussion symptom severity in injured children. Setting: Participants were recruited from a concussion clinic or the community. Participants: A total of 108 youth with concussion (72 symptomatic; 36 recovered) and 79 healthy youth (aged 9-18 years). Youth with concussion were included if aged 9 to 18 years, had no previous concussion within the last 12 months, less than 90 days since injury, and no known existing visual disorders or learning disabilities. Study Design: A prospective cross-sectional study. Main Measures: All participants were tested for OM and VO function with a commercial virtual reality (VR) eye-tracking system (Neuroflex®, Montreal,Québec, Canada). Participants in the concussion group who completed the postconcussion symptoms were scored with the Post-Concussion Symptom Inventory. Results: There was a significant group effect for vergence during smooth pursuit (F 2,176 = 10.90; P < .05), mean latency during saccades (F 2,171 = 5.99; P = .003), and mean response delay during antisaccades (F 2,177 = 9.07; P < .05), where children with symptomatic concussion showed poorer performance than clinically recovered and healthy children. Similar results were found in VO for average vestibular ocular reflex gain in the horizontal leftward (F 2,168 = 7; P = .001) and rightward directions (F 2,163 = 13.08; P < .05) and vertical upward (F 2,147 = 7.60; P = .001) and downward directions (F 2,144 = 13.70; P < .05). Mean saccade error was positively correlated to total Post-Concussion Symptom Inventory scores in younger clinically recovered children. Conclusion: VR eye tracking may be an effective tool for identifying OM and VO deficits in the subacute phase (<90 days) postconcussion.