Temporal dynamics of muscle optical properties during degeneration and regeneration in a canine muscle xenograft model.

We studied time-dependent changes in muscle optical properties during degeneration and regeneration using polarization-sensitive optical coherence tomography (PSOCT). Excised canine muscle transplants in a xenograft mouse model were imaged ex vivo from 3- to 112-day post-transplantation. PSOCT images were quantified to evaluate post-transplantation changes of three optical/structural properties: attenuation, birefringence and fiber alignment. The birefringence and fiber alignment decreased after transplantation until 20∼30-day and recovered thereafter. The attenuation coefficient showed a reversed trend over the same period of time. These results suggest that optical properties could be used for monitoring skeletal muscle degeneration and regeneration.