Research on Vascular Thrombosis Detection Methods Based on Fiber Bragg Grating Sensing

Thrombosis is a major cause of stroke. Current medical diagnosis and treatment of vascular thrombosis is mainly based on angiographic techniques using iodinated contrast agents, which expose both the physician and the patient to high doses of radiation, leading to risks and injuries. In this article, we propose a thrombus detection method based on fiber Bragg grating (FBG) sensors. First, a mathematical model related to thrombus-FBG strain for uniform and variable diameter blood vessels is constructed. Then, we reveal the correlation between blood flow, thrombus hardness, scale, and FBG strain through mathematical and thrombus biomechanical methods. On this basis, we develop an analytical model to detect the extent of vascular thrombus occlusion using FBG and confirm its efficacy in identifying thrombotic occlusions. Further experiments validate the correlation between FBG measurements and thrombus hardness. The experiments demonstrate that the maximum strain difference between high-hardness and low-hardness thrombi is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$9.89\mu \varepsilon $ </tex-math></inline-formula>. Finally, experiments validate the relationship between FBG strains and blood flow. Under varying blood flow conditions, the average strain difference generated by thrombus in regions adjacent to the FBG gratings is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4.48\mu \varepsilon $ </tex-math></inline-formula>. These findings demonstrate the potential of FBG sensors to detect thrombus locations across different blood flow rates.