INFRARED TOMOGRAPHY OF PORT-WINE-STAIN BLOOD-VESSELS IN HUMAN SKIN

Specifying the distribution of laser energy within a tissue is the fir st step towards understanding and capitalizing on a variety of laser-t issue interactions, Whether photothermal, photochemical or photomechan ical in nature, laser-tissue interactions begin with the absorption of photon energy. The spatial distribution of photon absorption specifie s the required laser exposure to be delivered and the extent of subseq uent therapeutic action. Using infra-red tomography (IRT), the broad, long-term objective of this research is the development of a tomograph ic reconstruction algorithm as a means to determine: (1) the depths an d physical dimensions of discrete subsurface port-wine-stain (PWS) blo od vessels in human skin; and (2) the initial space-dependent temperat ure increase in PWS blood vessels immediately following pulsed laser e xposure. In this report, preliminary studies are described which demon strate the potential application of IRT in the clinical management of PWS patients.