Premium
Noninvasive assessment of microcirculation of living organs and tissues using laser
Author(s) -
Kamada Takenobu,
Sato Nobuhiro,
Kakubari Naomichi,
Yoda Kiyoshi,
Kawano Sunao,
Schichiri Motoaki,
Abe Hiroshi
Publication year - 1983
Publication title -
lasers in surgery and medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 112
eISSN - 1096-9101
pISSN - 0196-8092
DOI - 10.1002/lsm.1900020311
Subject(s) - laser , irradiation , materials science , microcirculation , time constant , thermography , blood flow , chemistry , biomedical engineering , infrared , optics , medicine , physics , electrical engineering , nuclear physics , radiology , engineering
For studying microcirculation of intact tissues or organs, a new noninvasive, heat‐transient method using laser photoexcitation is described. As a heating source an argon ion laser or R6G dye laser was used via a quartz fiber optic guide. Infrared radiation from heated tissue was detected by a thermography apparatus. After switching the laser irradiation on and off, a thermal transient curve of a model tissue, the skin, was biphasic: a component with a fast time constant and the other with a slow time constant. The temperature increases of both phases following laser irradiation were linear to the applied power from the laser onto the tissue. The temperature rises as a function of the wavelength of irradiated light have shown that the absorption of the light by tissue hemoglobin is a main heat‐generation source. Furthermore, the temperature rises as a function of tissue blood volume and flow have shown that the component with a slow time constant is more related to the tissue hemoglobin concentration and tissue blood flow and heat conductivity. Thus, the analysis of heat‐transient curves following laser irradiation gives information as to regional tissue blood volume, blood flow, and tissue heat conductivity.