Infra-red tomography of port-wine-stain blood vessels in human skin

Specifying the distribution of laser energy within a tissue is the first step towards understanding and capitalizing on a variety of laser-tissue interactions. Whether photothermal, photochemical or photomechanical in nature, laser-tissue interactions begin with the absorption of photon energy. The spatial distribution of photon absorption specifies the required laser exposure to be delivered and the extent of subsequent therapeutic action. Using infra-red tomography (IRT), the broad, long-term objective of this research is the development of a tomographic reconstruction algorithm as a means to determine: (1) the depths and physical dimensions of discrete subsurface port-wine-stain (PWS) blood vessels in human skin; and (2) the initial space-dependent temperature increase in PWS blood vessels immediately following pulsed laser exposure. In this report, preliminary studies are described which demonstrate the potential application of IRT in the clinical management of PWS patients