A domestic research team has developed an optical imaging technology that can quantitatively measure changes in cerebral blood flow and speed. It is expected to present a new treatment for vascular diseases such as stroke.
GIST (Gwangju Institute of Science and Technology) Department of Biomedical Engineering Professor Jung Eui-Heon’s team developed a system that can quantitatively measure the change and speed of cerebral blood flow when a brain infarction occurs on the cerebral surface by analyzing speckle, which is an interference pattern created by irradiating a laser beam to the brain. announced on the 23rd that it was successful.
‘Laser speckle’ is a speckle-shaped interference pattern generated by the interaction between particles and laser light when a laser beam is irradiated onto an object such as a living tissue. In the case of living tissue, information such as blood cell movement is reflected in continuous speckle images. .
Although the human brain accounts for only 2% of the body mass, it consumes 20% of the body’s oxygen and nutrients. Therefore, measuring the change and rate of cerebral blood flow is very important for understanding cerebral metabolism and cerebrovascular pathology.
Existing research methods have limitations in measuring blood flow velocity, although changes can be seen before and after the movement of blood flow. Gist’s research team devised a method that can quantitatively measure the speed of blood flow changing in real time only by speckle analysis without mathematical modeling or correction to solve this fundamental problem. As a result, it is now possible to objectively compare the efficacy of new treatments for vascular diseases by showing real-time quantitative velocity maps of blood flow changes in a preclinical ischemic stroke model.
In particular, this study utilized the principle that the real-time movement of blood cells in blood vessels in living tissue is reflected in laser speckle. In other words, it succeeded in quantitatively finding the actual velocity field by viewing speckle as a kind of particle and analyzing spatiotemporal changes. For this, an extremely short camera exposure time is required, and the research team explained that it could be applied to animal disease models by implementing it using an optical and acoustic modulator.
Professor Chung Eui-heon said, “This study overcomes the limitations of the existing laser speckle imaging and presents a methodology that can quantitatively analyze the blood flow rate in vivo, and is expected to be applied to the development of animal models-based stroke treatment and clinical research for vascular diseases in the future. do,” he said.
This research was led by Gist Professor Chung Eui-heon (corresponding author) and conducted by Ph.D. student Moshin Kureshi (first author) of the Department of Biomedical Engineering. This was done with support from the National Research Foundation of Korea’s Mid-Range Researcher Support Project and the GIST Research Institute (GRI). The related paper was published online on August 13, 2021 in ‘Optica’, a renowned academic journal in the field of optics.
