2017 年 17 巻 1 号 p. 52-56
Rheological behavior of interstitial fluid in epidermal tissue, including blood micro-circulation, can vary skin mechanics in micro scale, i.e. visco-elasticity. Therefore, an in vivo quantitative measurement of fluid velocity is necessary to clarify their properties. In this paper, we constructed OCDV (Optical Coherence Doppler Velocigraphy), which is a method of tomographic micro-visualizing interstitial fluid velocity using a high frequency modulated low coherence interferometer. The tomographic detection of modulated Doppler frequency can determine fluid velocity profile within tissue. An optimal signal processing of OCDV was evaluated alternately on short time FFT and Hilbert transform, and validated by measuring the fluid velocity of Intralipid solution (2%) in micro channel. Consequently, Hilbert transform has further advantages in the accuracy even with a rapid scanning system than short time FFT. OCDV was suggested to be effective to diagnose flow velocity profiles in tissue non-invasively and tomographically.
