Spectroscopic detection of bladder cancer using near-infrared imaging techniques.

High-contrast imaging of bladder cancer is demonstrated using near-infrared autofluorescence under long-wavelength laser excitation in combination with cross-polarized elastic light scattering. Fresh unprocessed surgical specimens obtained following cystectomy or transurethral resection were utilized and a set of images for each tissue sample was recorded. These images were compared with the histopathology of the tissue sample. The experimental results indicate that the intensity of the near-infrared emission as well as that of the cross-polarized backscattered light was considerably different in cancer tissues than in that of the contiguous nonneoplastic tissues, allowing an accurate delineation of a tumor's margins.