Feasibility of Using Smartphone Eye Tracking for Self-Recording Positional Tests.

Introduction: Benign paroxysmal positional vertigo (BPPV) is a common cause of dizziness that is diagnosed by detecting nystagmus through positional maneuvers. Limited access to expert clinicians to correctly perform and interpret the eye movement findings of positional tests can hamper the diagnosis and delay the treatment. We aimed to assess the usability of a smartphone-based eye-tracking application (EyePhone) for self-recording eye movements during positional testing. Methods: Healthy volunteers were enrolled and provided instructions to perform Dix-Hallpike and Supine Roll tests using the EyePhone application to record themselves. A study team member was instructed to observe the process without interfering. They recorded the time each section took and the accuracy of performing positional tests. Usability was assessed using the mHealth App Usability Questionnaire (MAUQ), and expert evaluation of recorded videos determined quality. Results: All participants successfully performed the tests and recorded their eye movements. On average, after watching the instruction, it took participants 3 min 31 s to record the Dix-Hallpike test and 3 min 4 s to record the Supine Roll test. Nine participants completed Dix-Hallpike without major errors, and all completed the Supine Roll successfully. An expert review found that 95% of videos had clear eye visibility. Participants rated the app as easy to use and stated that they would use the app again. Conclusion: We demonstrated the usability and feasibility of the EyePhone app for self-recording positional tests. This application offers the potential for remote BPPV diagnosis and improved patient access to care.