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Updated: Aug 16, 2026

Diffuse Reflectance Spectroscopy: Getting the Capillary Refill Test Under One's Thumb
Published on: December 2, 2017
Depth visualization of a local blood region in skin tissue by use of diffuse reflectance images
Izumi Nishidate1, Yoshihisa Aizu, Hiromichi Mishina
1Department of Bio-system Engineering, Yamagata University, 4-3-16, Jonan, Yonezawa, Yamagata 992-8510, Japan.
Abstract:
A simple method is proposed for visualizing the depth distribution of a local blood region in skin tissue by using diffuse reflectance images at two isosbestic wavelengths of hemoglobin, 420 and 585 nm. Monte Carlo simulation of light transport specifies a relation between optical densities and the depth of the region under given concentrations of melanin in the epidermis and blood in the dermis. Phantom and in vivo experiments were performed to show the usefulness of the method.

