Objective: Despite an increase in the awareness and diagnosis of mild traumatic brain injury (mTBI), there remains a paucity of data examining the comparative efficacy of available assessments. This study aims to validate visual functions as potential biomarkers for mTBI.
Methods: This case-control correlational design utilizes military personnel diagnosed with acute (≤72 h post-injury) mTBI (n = 100) and age-matched controls (n = 100) to examine the relative effectiveness of the pupillary light reflex (PLR), near point of convergence (NPC) break, King-Devick (KD) test time, and Convergence Insufficiency Symptom Survey (CISS) score to discriminate between participants with mTBI.
Results: Three of the eight PLR parameters (i.e., average constriction velocity (ACV), average dilation velocity (ADV), and 75% re-dilation time; all p < 0.001) were affected in mTBI participants. Similarly, NPC break, KD test time, and CISS scores showed a statistically significant difference between groups (all p < 0.001). Area under the curve showed that ADV (0.82) and NPC (0.74) have the higher predictive values of all objective parameters.
Conclusions: ADV, ACV, and NPC break are objective visual functions markedly affected in the acute mTBI group compared with controls; therefore, we proposed that they could be used as biomarkers for acute mTBI.