Visual Tracking As A Potential Marker For Exercise Tolerance Levels After Concussion

PURPOSE: Investigate how visual tracking abnormalities as assessed by objective oculomotor tracking testing (OOTT) correlate with exertional tolerance after concussion. METHODS: This is a retrospective cohort study of 384 patients with mTBI aged 8 to 77, treated at a concussion center. A concussion specialist evaluated patients and they underwent AR exertional testing alongside OOTT. Patients completed varied AR intensities based on their heart rate (HR) and rate of perceived exertion (RPE). This includes the following AR zones: step 1 (HR 100-120, RPE 3-4), step 2 (HR 120-140, RPE 5-6), step 3 (HR 140-160, RPE 7-8), step 4 (HR 160-180, RPE 9-10), and Step 5 (HR 160-180, RPE 9-10), which includes multi-directional high intensity interval training (HIIT-MD). A concussion specialist determined what AR step was achieved based on HR, RPE, symptoms/signs, orthostatic testing and pre/post KD, sway velocity testing. Patients complete OOTT in which a machine assesses their ability to track a video with their eyes. The video is played continuously in a square aperture while moving clockwise along the outer edges of a rectangular viewing monitor at a rate of 10 s per side for five complete cycles of 40 s each, totaling to 220 s (Samadani, 2022). An OOTT summary score is then generated. Scores range 0-20 with a lower score indicating better visual acuity. The AR step achieved was then correlated to the OOTT summary score and a p-value was calculated. RESULTS: The correlation coefficient for AR step and OOTT is -0.1028 with a p-value of 0.044. CONCLUSION: There is a strong negative correlation that is statistically significant. Better or lower OOTT scores correlated with higher physiologic exercise tolerance. This demonstrates the efficacy of OOTT in evaluating visual improvements in an mTBI patient as they progress through treatment and exertional rehab. Further studies with OOTT may demonstrate its capacity to be predictive of one's therapeutic exertional zone after concussion.