Reliability of a Smooth Pursuit Eye-Tracking System (EyeGuide Focus) in Healthy Adolescents and Adults

Abstract

Mild traumatic brain injury (mTBI) is the most common brain injury, seen in sports, fall, vehicle, or workplace injuries. Concussion is the most common type of mTBI. Assessment of impairments from concussion is evolving, with oculomotor testing suggested as a key component in a multimodality diagnostic protocol. The aim of this study was to evaluate the reliability of one eye-tracking system, the EyeGuide Focus. A group of 75 healthy adolescent and adult participants (adolescents: n = 28; female = 11, male = 17, mean age 16.5 ± 1.4 years; adults n = 47; female = 22; male = 25, mean age 26.7 ± 7.0 years) completed three repetitions of the EyeGuide Focus within one session. Intraclass correlation coefficient (ICC) analysis showed the EyeGuide Focus had overall good reliability (ICC 0.79, 95%CI: 0.70, 0.86). However, a familiarization effect showing improvements in subsequent trials 2 (9.7%) and 3 (8.1%) was noticeable in both cohorts (p < 0.001) with adolescent participants showing greater familiarization effects than adults (21.7% vs. 13.1%). No differences were observed between sexes (p = 0.69). Overall, this is the first study to address the concern regarding a lack of published reliability studies for the EyeGuide Focus. Results showed good reliability, suggesting that oculomotor pursuits should be part of a multimodality assessment protocol, but the observation of familiarization effects suggests that smooth-pursuit testing using this device has the potential to provide a biologically-based interpretation of the maturation of the oculomotor system, as well as its relationship to multiple brain regions in both health and injury.

In-Season Test–Retest Reliability of Visual Smooth-Pursuit (EyeGuide Focus) Baseline Assessment in Female and Male Field-Sport Athletes

“…To our knowledge, this is the first study to successfully implement pre-test familiarization using EyeGuide Focus (see Figure 2 ). These findings have shown that 2–4 practice trials are sufficient to offset familiarization effects seen in previous EyeGuide Focus research [ 24 ]. The group scores obtained in the current study (mean = 22,254.49 ± 5907.67 AUs) are lower than those reported in the original EyeGuide study (mean = 29,633.05 ± 9209.84 AUs) [ 21 ], higher than those reported in pro mixed-martial arts athletes (mean = 17,426.06 AUs) [ 28 ], but almost identical to scores recently reported in adults in their first trial (mean = 22,503.33 ± 7014.32) [ 24 ].…”

“…There may be a number of reasons for the variations observed with this tool to date. Pearce et al recruited a population of physically active participants with no history of concussion, TBI, or visual conditions who were also not taking medication [ 24 ]. This differs from the present study and Fuller and Brown’s study, where previously concussed athletes and those with visual conditions were not excluded [ 25 ].…”

“…Participants performed 2–4 practice trials before performing three official trials at each testing session. These were performed as familiarization effects have been detected in previous research with the device [ 24 ]. Participants were given 30–60 s between subsequent measurements to prevent fatigue.…”

“…EyeGuide Focus has achieved varying levels of intra-session reliability in recent research, and learning effects have been identified in athletes [ 24 , 25 ]. To the authors best knowledge, no study of inter-session reliability has been conducted with the tool to date.…”

“…The device has also been used beyond SRC research in peer- and non-peer-reviewed studies to explore workplace fatigue [ 26 ], the effectiveness of visuomotor training [ 27 ], and the impact of mixed martial arts bouts on scoring [ 28 ]. Age-related differences in EyeGuide Focus scoring between adults and adolescents have been observed [ 24 ]. Such differences in ocular assessments of young athletes are not uncommon and emphasize the need for periodical baseline assessments [ 29 , 30 ].…”