Development of a smartphone-based video-oculography system for neurootological diagnostics

Introduction 

With an annual prevalence of 11%, vertigo syndromes are very common, but can only be specifically diagnosed in less than 20% of cases. In addition, the misallocation of cranial imaging in particular contributes to an immense socioeconomic burden. Apparatus-based diagnostics such as video-oculography (VOG) are often characterized by outdated and expensive sensor technology as well as low availability. Current smartphones integrate sophisticated camera systems that allow robust tracking of eye and head movements and thus offer widely available and affordable alternatives for neurootological diagnostics. 

Material & methods 

A native app prototype for the mobile operating system iOS was developed, which uses the TrueDepth camera of current iPhones to record and display two-dimensional time series data of eye and head movements with a temporal resolution of 60 Hz. In addition, the replay option of standardized stimuli (optokinetic nystagmus, eye-tracking test) with variable speed was integrated.

Results 

With the app prototype, measurements of eye and head movements could be performed with high spatiotemporal precision in healthy subjects. The provocation of the optokinetic nystagmus allowed a sufficient determination of intensity and direction of the nystagmus. Furthermore, it was possible to perform caloric testing of the vestibular organs with presentation of corresponding stimulus nystagmus.

Discussion 

Our results demonstrate that smartphone-based neurootological diagnostics has the potential to realize mobile, accurate and cost-effective solutions based on quantitative data in different scenarios.

Publication History

Article published online:
24 May 2022