Fluorescence tomography of

biological tissue using ultrasonic tagging Masaki Kobayashi and Motohiro Takeda Ultrasound-induced modulation permits the collection of fluorescence images from deep within light-scattering media. Fluorescence labeling traces specific molecules that play phys-iological roles in living organisms, revealing the mysteries of life. Recently developed fluorescent probeswith excellent optical performance are expected to extend fluorescence techniques to clinical diagnosis. However, living tissues scatter light strongly, restricting applications to the microscopic level or to the body surface. To permit noninvasive optical measurement for tomo-graphic imaging of the human body, we have explored a tech-nique to visualize fluorescence at a depth of tens of centimeters, with resolution of the order of millimeters