血管内膜内光増感色素のレーザー光励起蛍光分光特性の検討

Abstract

We studied experimentally the spectral properties of laser-excited Fluorescence of three photosensitisers, namely tetracycline (Tc), hematoporphyrin free base (Hp) and chlorin e6Na (Chl), taken up in human intima. Excitation source used is third-harmonic beam (355nm) of a Nd:YAG laser, whose irradiated power and beam diameter are approximately 10uW and 100um, respectively. Three photosensitisers (concentration, Hp and Chl: 1×10-4mol/l and Tc: 1×10-3 mol/l) were administrated to resected human vessels for 2 hours in vitro.The main result obtained in our study are following;1) Photosensitisers examined are confirmed to be taken up in intima and the fluorescence intensity decreases as the time goes on.2) The fluorscence intensity of three dyes is different with measuring positions of intima and the fluoresence intensity from atheromatous plaque is usually stronger than that from normal region.3) The fluorescence intensity of human vessel decreases when photosensitiser is administrated, especially in the ease of Hp and Chl. This phenomenon could utilized to estimate quantitatively the concentration of dye taken up in each positjons in the vessel.