The occurrence, development and curative effect of many diseases are relative to the structure and function of
hypodermic blood vessels. The optical imaging techniques may be available, but suffer from the limited penetration of
visible and near infrared light caused by the high scattering of skin. The tissue optical clearing technique based on
immersion of tissues into optical clearing agents (OCAs), proposed by Tuchin, can improve the depth to which light
penetrates. However, it is still difficult to meet skin in vivo except for OCAs hypodermic injection. In this study,
THIAZONE as a new penetration enhancer mixed with polyethylene glycol (PEG-400), was typically applied to rats'
skin in vivo. The optical clearing process of skin was monitored with CCD camera, and the deep blood flow information
of skin was acquired by using of laser speckle contrast imaging technique. The results show that the skin became
transparent after 12 minutes, the vessels were clear. After 40 minutes, acting saline on the interested region, we observed
a recovery of the skin. This work is very significant for medical diagnosis since it is able to acquire the structure and
function information of blood vessels in deep skin in vivo with
non-invasive optical method.