An assessment of the accuracy and usability of a novel optical wound measurement system

Abstract

Aims: Measurement of wound size can predict healing and provide information to guide treatment. This study assesses a novel optical wound imaging system that creates a three-dimensional image of the ulcer. Methods: Using a new camera-based digital system and traditional elliptical wound measurements, 36 foot ulcers from 31 patients (aged 44-94 years, median 70 years) were examined during a 12-week period at two centres. Median diabetes duration was 18 years (range 6-56 years). Seventeen percent had Type 1 diabetes, 93% had peripheral neuropathy and 57% had peripheral artery disease. Twenty-five were reviewed consecutively, resulting in 76 ulcer examinations. Median ulcer size was 94 mm2, with size ranging from 3.1 to 2195 mm2. Results: Pearson, Spearman and Kendall rank coefficients showed a strong correlation (in all cases P < 0.001) between digital measurements of wounds against traditional hand-measured estimates. Intra-observer variation of wound length using digital elliptical measurement (DEM) gave a coefficient of variation of < 3.0%. Interobserver variation of wound length using DEM was < 6.5%. Variation from a standard known-size wound area was < 8.0% across 30 trials. Conclusions: This study shows a strong correlation between digital and traditional measurement techniques. The system can be easily deployed in routine clinical practice, providing an objective visual record, allowing remote in-depth analysis. © 2009 The Authors.