Four-dimensional optical coherence elastography (OCE) for assessing cutaneous leishmaniasis lesions and treatment response in murine model

Cutaneous leishmaniasis (CL) is the most common form of leishmaniasis, manifesting as skin lesions that can lead to scarring and may have lifelong impacts on well-being. Early and accurate assessment of lesion biomechanics could enhance diagnosis and therapeutic monitoring. In this study, we evaluate the feasibility of four-dimensional (4D) dynamic optical coherence elastography (OCE) for in vivo characterization of CL lesions in murine model. Four mice at distinct disease stages: healthy baseline, day 1 post-infection, developed lesion, and post-treatment, were scanned. Volumetric elasticity values were obtained by calculating local elastic wave velocities. Healthy skin exhibited uniform wave propagation with an average Young’s modulus of 19±2 kPa, and a similar value was observed at day 1 post-infection (20±5 kPa). In contrast, developed lesions displayed markedly increased stiffness (511±238 kPa), which decreased following treatment (68±27 kPa). These findings demonstrate that 4D dynamic OCE can quantitatively and non-invasively detect biomechanical changes associated with CL progression and treatment response, supporting its potential as a diagnostic and monitoring tool in clinical settings.