Update VertiGo - continuation of the VNG via mobile webcam

Background Dizziness is one of the most common symptoms in medicine and its diagnosis is complex. Nationalwide this diagnostic is not always available in Germany. In order to improve this, a preliminary study has already shown that horizontal video nystagmography (VNG) is possible using a mobile webcam. The aim of this study was whether the nystagmus detection can be increased with an additional light source.

Methods In the continued feasibility study, 20 healthy volunteers participated in a bilateral caloric test and VNG using a mobile webcam. The probands gazed into an external light source close to the camera during the recording. The recording was analyzed with a software developed using computer vision techniques. An algorithm detected a sequence of horizontal pupil positions. The software differentiated between the presence or absence of nystagmus using a threshold of at least two nystagmus in the same direction. The subjective perception of dizziness was assessed using a visuel analog scale (VAS).

Results When considering above threshold, an accuracy of 49.15 % , a positive predictive value of 84.61 %  and a sensitivity of 28.20 %  were achieved. In the preliminary study without an additional light source an accuracy of 39.66 % , a positive predictive value of 70 %  and a sensitivity of 17.95 %  were detected. All subjects reported symptoms of dizziness with an average VAS of 2.9.

Summary In the present study, the nystagmus detection could be improved slightly compared to the previous study. Further adjustments and tests of the software are necessary in the future in order to increase its accuracy.

Poster-PDF A-1407.pdf

Publication History

Article published online:
13 May 2021