Feature Of The Week 4/11/10: Noninvasive Assessment of Healing of Bacteria Infected and Uninfected Wounds using Optical Coherence Tomography
Feature Of The Week 4/11/10: Microbial infection is one of the major factors for the impairment of wound healing as the microbial toxins have a detrimental effect on collagen in the wounded tissue. Infected wounds can cause increased trauma, could severely compromise the overall health of an individual as well as increase the cost of treatment. To facilitate a faster healing of wounds it will be desirable if the signatures of microbial infection in wounds can be monitored non-invasively. OCT is an ideal non-invasive imaging technique for this purpose as it provides high-resolution cross-sectional images of tissues with considerable penetration depth (1-2 mm).
Researchers at Raja Ramanna Centre for Advanced Technology, Indore, India, have recently used Polarization-sensitive OCT to monitor the changes in the morphology of the tissues of the infected and uninfected wounds resected at different healing times and compared the OCT measurements with the corresponding histological measurements. Their study showed that as compared to uninfected wounds, in infected wounds prominent edematic regions were observed in addition to a significant delay in reepithelization and collagen remodeling phases of wound healing. The latter was monitored via measurement of the change in collagen matrix birefringence. Good correlation was found between the morphological measurements made by OCT and the histological measurements. A real time (~ 8 frames/s) OCT set up could therefore be used to monitor the healing of an infected wound non-invasively without sacrificing the animal. The results demonstrate the potential of OCT for monitoring the signatures of microbial infection in wounds as well as progression of wound healing.