Error rate of automated calculation for wound surface area using a digital photography

• Published in: Skin research and technology 2018-02, Vol.24 (1), p.117-122
• Main Authors: Yang, S., Park, J., Lee, H., Lee, J. B., Lee, B. U., Oh, B. H.
• Format: Article
• Language: English
• Subjects: Algorithms; Automation; Cameras; Curvature; Digital photography; Error analysis; Error correction; Facial Injuries - pathology; Facial Injuries - physiopathology; Humans; image analysis; Photography; Photography - instrumentation; Photography - methods; Single lens reflex; Skin; Skin - injuries; Skin - pathology; Smartphone; Smartphones; Surface area; Wound Healing; wounds and Injuries
• ISSN: 0909-752X; 1600-0846
• DOI: 10.1111/srt.12398

Background Although measuring would size using digital photography is a quick and simple method to evaluate the skin wound, the possible compatibility of it has not been fully validated. Purpose To investigate the error rate of our newly developed wound surface area calculation using digital photography. Methods Using a smartphone and a digital single lens reflex (DSLR) camera, four photographs of various sized wounds (diameter: 0.5‐3.5 cm) were taken from the facial skin model in company with color patches. The quantitative values of wound areas were automatically calculated. The relative error (RE) of this method with regard to wound sizes and types of camera was analyzed. Results RE of individual calculated area was from 0.0329% (DSLR, diameter 1.0 cm) to 23.7166% (smartphone, diameter 2.0 cm). In spite of the correction of lens curvature, smartphone has significantly higher error rate than DSLR camera (3.9431±2.9772 vs 8.1303±4.8236). However, in cases of wound diameter below than 3 cm, REs of average values of four photographs were below than 5%. In addition, there was no difference in the average value of wound area taken by smartphone and DSLR camera in those cases. Conclusion For the follow‐up of small skin defect (diameter: