The laser doppler blood flow measurement technology achieves the measurement of blood flow and velocity by using laser irradiation on moving red blood cells within the human body, generating doppler frequency shifts. Compared to other blood flow measurement techniques, its output signals exhibit a strong linear relationship with blood flow, allowing for a more accurate reflection of changes in blood flow. This technology provides a convenient, user-friendly, non-invasive optical detection method for various applications, including clinical surgical assistance, blood perfusion monitoring, drug efficacy assessment, and pathological research. Ensuring the accuracy of blood perfusion measurements and the depth of tissue measurements, especially under dynamic conditions, is a key technology in the research and application of laser doppler blood flow measurement devices. This review introduces the working principles of laser doppler blood flow measurement technology, outlines the research progress of this technology and related devices in various clinical application areas, analyzes key issues influencing the accuracy of its clinical applications and the research progress of relevant technologies. It also provides prospects for the future development of this technology and its devices, offering valuable insights for the research and development of wearable microcirculation measurement devices.
KEYWORDS: Control systems, Temperature metrology, Nozzles, Infrared radiation, Thermography, Control systems design, Microcontrollers, Telecommunications, Design and modelling, Power supplies
The coolant liquid nitrogen, which is commonly used in medical treatment at present, is prone to frostbite and vaporization, and the greenhouse effect of Freon is serious. With the high-speed development of CO2 liquid storage technology, we design an STM32-based control system for cryogenic shock therapy using CO2 as coolant. The control system uses STM32F103RCT6 microcontroller as the core processor with modular design, including main control module, infrared temperature measurement module, human-computer interaction module, serial communication module, control output module, power supply module and so on. The modules work together to realize the functions of serial communication, real-time temperature monitoring, solenoid valve start-stop control, etc. The distance between the nozzle and the cooling substrate and the effective area of cooling are studied quantitatively by experiment under the straight tube type nozzle with 0.5mm inner diameter and 4cm length model. The results show that the control system is stable and practical, and the ideal distance between the 0.5mm*4cm nozzle and the cooling substrate is 30mm for the best cooling effect, and the effective range is the ellipse area of 1.8cm for the long half-axis and 0.9cm for the short half-axis, which provides a reference for clinicians to perform spray treatment operation on the damaged tissue epidermis of patients.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.