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An international research group detected alterations in capillary blood flow around the face caused by body position change using photoplethysmography. Using this method, scientists can examine blood vessels located in the carotid system in order to investigate the cerebral blood flow response to various stimuli in health and disease.
This optical method allows researchers to detect both the velocity of the pulse wave moving from the heart to tissues, and amplitude of blood pulsations in different areas of the body. Using imaging photoplethysmography, researchers from the ITMO University in collaboration with colleagues from the Almazov National Medical Research Centre managed to find out that pulse wave velocity (PWV) in the carotid area changes in response to body position change.
When researcher examined migraine patients, they noticed that the way they moved affected the results of the observations. Different people demonstrated different responses to body position change, which shows that this new method of pulse wave velocity detection provides valuable information on the regulation of the peripheral blood flow. According to the researchers, the significance of the research helps to understand the interaction between light and the circulatory system and how researchers can use the interaction for diagnosis.