Coherent Detection Imaging Method Using Lasers. Achievement of Laser CT(Computed Tomography) for Biomedical Applications

In this paper, we report and discuss the achievment of laser absorption computed tomography of actual in vivo/in vitro biological objects using the Coherent Detection Imaging (CDI) method. This CDI scheme offers the feasible and reliable means for the computer-assisted optical tomographic imaging based on the optical heterodyne technique that has excellent directionality and very high sensitivity. We have experimentally demonstrated the fulfillment of fundamental conditions for the establishment of laser absorption tomography by our novel CDI method in highly scattering and absorptive media such as actual biological tissues and objects. Thus we have realized the tomographic image reconstruction of several biological objects including plant stems, chicken tissue, whole egg, struma specimen and new-born mouse brain employing the projection slice theorem.