Clinical system for skin tumour detection by fluorescence lifetime imaging

A portable system based on Fluorescence Lifetime Imaging has been developed and tested for the detection of skin tumors in humans. The Heme precursor /spl delta/-aminolevulinic acid, which promotes the preferential accumulation of the endogenous Protoporphyrin IX in proliferative tissues, is used as an exogenous marker to target the tumor. Then, using a gated intensified camera, two or more images of the sample are acquired after different delays with respect to the excitation pulses. The images are processed in order to calculate the spatial map of the fluorescence decay time of the sample. The localization of the tumor is based on the longer decay time detected in neoplastic tissues with respect to healthy ones.