Comparison between clinical and computational method of surface measurements of skin ulcers caused by Cutaneous Leishmaniasis

Abstract

Cutaneous leishmaniasis is a neglected disease caused by an intracellular parasite of the genus Leishmania. The implementation of new techniques for its monitoring is increasing. This article presents a methodology based on photogrammetry for the follow-up and evaluation of skin ulcers caused by cutaneous leishmaniasis. Leishmaniasis was experimentally inoculated into golden hamsters, which were analyzed during and after treatment for four months. The follow-up of the evolution of the disease is carried out by taking clinical (manual) and computational measurements. The clinical data were obtained using a caliper, measuring directly on the ulcerated area and performing calculations of geometric approximations with sizes similar to the ulcerated area (square and elliptical). Computational data was obtained by Agisoft PhotoScan software using a photogrammetry-based 3D reconstruction technique to model and extract information from the surface. Validation is carried out on the size of the cutaneous ulcerative areas under study, comparing the square and elliptical approximation of the area with that calculated by the software (total area of the 3D surface generated from the point cloud). This validation is performed by graphically comparing the trend in the variation of the ulcer area of each hamster, and an area correlation calculation (clinical vs computational measurements). As a result, 60% of the study population presents a strong correlation with a value of 0.8. We found that the computational technique allows physicians to provide a more reliable concept during ulcer healing follow-up.