ACCUMULATED PHOTON-ECHO IMAGING FOR TISSUE SAMPLES

Microscopic mapping of accumulated photon-echo relaxation time, known as accumulated photon-echo imaging, has been developed as a new techni que accessible to histological diagnosis. Photon-echo imaging for Rhod amine-stained tissue samples of human liver has been demonstrated by m eans of fluorescence detection of accumulated photon echo. In a liver tissue that included a moderately differentiated hepatocellular carcin oma, we obtained an accumulated photon-echo image that correlated with the histological diagnosis. However, for a liver tissue with a highly differentiated hepatocellular carcinoma, photon-echo imaging could no t discriminate the carcinoma from a noncancerous liver tissue. (C) 199 7 Optical Society of America.