Development of a recording system for nystagmus and head positions using the iPhone

We report a nystagmus recording system using the iPhone. The greatest advantage of this system is that nystagmus can be recorded anytime and anywhere using the iPhone. In addition, the system can synthesize the head position information as an animation over the nystagmus image. We previously reported a nystagmus and head position capture software for windows PC. We ported this software for Windows PC to this iPhone system. The software for Windows PC that we reported earlier needs medical infrared Frenzel goggles and a self-made motion sensor device. The system that we report herein needs only an iPhone. The iPhone camera is used to record the nystagmus, the head position information is obtained from the motion sensor built into the iPhone, and the head position information is synthesized as an animation over the nystagmus image using the iOS app. The iPhone camera has an infrared filter, which has the disadvantage of not being able to shoot nystagmus in the dark with infrared lighting, but it is considered to be sufficiently useful as a method for recording nystagmus during dizziness at-tacks.