A new digital image analysis system useful for surface assessment of vitiligo lesions in transplantation studies

So far there is no uniformity in the evaluation methods used in the assessment of treatment outcome in vitiligo studies. The ability to objectively measure surfaces of vitiligo lesions is important for both clinical practice and research. Our objective was to assess the reproducibility, accuracy, user-friendliness and time effectiveness of a new digital image analysis system for surface measurement of vitiligo lesions. Three different observers performed both a visual estimation and a digital image analysis on 30 images of 10 vitiligo lesions. Inter- and intra-observer variation were evaluated and results were compared with the 2D gold standard measurements and a 3D measurement. A high inter- and intra-observer variability was observed for the visual estimation of surfaces. With the digital image analysis system a significant improvement of the reproducibility was achieved (p = 0.01). Moreover, results were accurate and the measurement procedure was user-friendly. Importantly, a systematic underestimation was demonstrated when comparing the 2D with the 3D measurements. We introduced an objective measurement method that might be useful in the future for consistently measuring surfaces of selected vitiligo lesions both before and after different therapeutic modalities.