The Study Of Ultrasound Imaging In Intravascular Ultrasound-OCT System

At present,the death toll of coronary heart disease is about 1 million in China each year,and the rupture of vulnerable plaque is an important cause of acute coronary heart disease.At present,the means to obtain the information of plaque vulnerability include ultrasound technology and OCT technology.The depth of Intravascular ultrasound imaging can be used to imaging the structure of each membrane layer and the shape of vulnerable plaque in macroscopic but its resolution is low,it is difficult to observe the fine structure of plaque,which cannot effectively identify vulnerable plaque.The high resolution of intravascular OCT imaging can obtain finer morphological information of plaque,and the thickness of the fiber cap of the vulnerable plaque was measured,but the OCT was weak and the whole structure of the plaque could not be evaluated.In view of the inability to obtain all morphological information of coronary plaque in both of these techniques,intravascular ultrasound and intravascular OCT were combined to achieve early detection of intravascular thrombosis and plaque.The main work of this paper is as follows:1.The intravascular ultrasound-OCT Endoscopic imaging System was grasped,completing the functional module division;2.A "back-to-back" ultrasonic-OCT probe was designed and realized the real-time imaging of the same section in the blood vessel.3.A near-end drive module is designed to realize the rotation control and signal coupling of intravascular ultrasonic-OCT probes.4.The design completes the ultrasonic imaging system circuit,including the ultrasonic transmitting and receiving circuit and the signal conditioning circuit,which realizes the transmitting,receiving and preprocessing function of the ultrasonic signal.5.The completion of ultrasonic echo signal processing algorithm,to achieve the ultrasonic echo signal envelope extraction,depth modification and image data compression,to get suitable for display gray pixel data.6.The design completes the intravascular ultrasonic-OCT system communication interface,including the interface protocol,the hardware circuit and the software development,which has realized the upload ultrasonic image as well as the lower pass control parameter function;7.The Ultrasonic-OCT imaging experimental platform was constructed to simulate the vascular tissue simulation sample,and the feasibility and stability of the system were validated.