Yukio UEDA, Kazuyoshi OHTA and Yutaka YAMASHITA

Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita, Shizuoka 434-8601, Japan

(Received July 6, 2004; Accepted May 30, 2005)

Our research goal is to develop diffuse optical tomography (DOT) capable of quantitative measurement. Information on optical pathlength is essential for reconstructing images with quantitative properties, and we have performed image reconstruction with a simulation model using a time-resolved photon path distribution (time-resolved PPD). The results showed that a DOT image reconstruction algorithm using this PPD is effective in quantifying the absorbers in a scattering medium such as human tissue. This algorithm uses a photon distribution independent of absorption by simply assuming that the measurement object is homogeneous, which means that PPD needs to be calculated only once. Our technique is therefore applicable to short-time imaging of measurement objects for which absorption changes flatness such as that in human tissue.

Key words: diffuse optical tomography (DOT), photon path distribution (PPD), time-resolved PPD