Visual assessment of digital ulcers in systemic sclerosis analysed by eye tracking: implications for wound assessment

The assessment of digital ulcers (DUs) in systemic sclerosis (SSc) depends crucially on visual aspects. However, little is known about the differences in visual assessment of these wounds between experts and non-experts or medical lay persons (novices). To develop potential training recommendations for the visual assessment of digital ulcers in SSc, we analysed gaze pattern data during assessment of digital ulcers between assessors with different levels of expertise.

Gaze pattern data from 36 participants were collected with a mobile eye tracking device. 20 pictures from digital ulcers of SSc patients were presented to each participant. The analysis comprised the scan path, the dwell times (for areas of interest), fixation counts and the entry time for each picture and subject.

Most significant differences were found between novices and medically educated groups. Dwell times in the wound area for novices differed statistically significantly from all medically educated groups (1.76s-3.1s less). Above all, novices had lower dwell times in wound margin and wound surrounding and spent more time in other areas (up to 1.92s longer). Correspondingly, they had less fixation points and longer overall scan paths in wound areas. Similar gaze pattern data were generated for medically educated groups.

For the first time, we could analyse the visual assessment of digital ulcers in SSc and detected differences according to levels of medical education and expertise. Adequate training on proper interpretation of changes in all wound areas are warranted to improve wound assessment in digital ulcers.