In vivo light dosimetry during superficial photodynamic therapy

The depth distribution of 630 nm laser light has been measured for ten patients during the photodynamic therapy of skin lesions by the application of topical 5-aminolaevulinic acid followed by surface illumination. Results show that the light distribution can be described by the diffusion theory. The values of effective attenuation coefficient obtained for each lesion are in close agreement (0.352 mm-1 +/- 8%) but the K value, used to describe sub-surface fluence build-up, varies between 0.12 and 8.23, although similar values are obtained for the same type of lesion.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.