Real-time microscopic visualization of tissue response to laser thermal therapy.

We present methods for visualizing the dynamic response of biological samples to laser-induced heating. Our approach utilizes optical frequency-domain imaging to detect, spatially localize, and monitor unique dynamic signatures that arise within zones of active tissue denaturation. Since this information is precisely registered with high-resolution ( approximately 10 microm) cross sectional images, regions of thermally destroyed tissue can be mapped in relation to pre-existing morphology. Using porcine esophageal specimens ex vivo, we demonstrate that the extent and evolution of laser thermal damage can be assessed in real time.