Research On Mechanical Rotational IVUS Catheter

As one of the three,"killers" of human health,cardiovascular disease is one of the diseases with the highest mortality rate currently.Coronary heart disease,or coronary atherosclerosis,is one of the most common cardiovascular diseases.The main cause of coronary heart disease is due to the rupture of fragile plaques,so early detection is an important means of prevention and treatment.At present,the usual clinically commonly used interventional testing method is intravascular ultrasound or IVUS.However,due to the existence of non-uniform rotational distortion artifacts in the ultrasonic probe,the image quality is reduced,which increases the difficulty of diagnosis of disease.The phenomenon of non-uniform rotational distortion is caused by friction be-tween the external drive and the pipe wall during long-distance transmission through the flexible shaft.To solve this problem,the paper studies a miniature piezoelectric motor,which is directly driven by placing it directly at the front of the ultrasonic probe inside the blood vessel,so that the production of uneven rotation can be avoided in the principle.Using the piezoelectric ceramic tube with a diameter of 1mm as the main part of the motor to design the motor model,we use infinite software COMSOL to simulate the tube,analyzing the static and dynamic characteristics of piezoelectric ceramic tube,and studying the influence of the length and thickness of the ceramic tube on its perfor-mance,so as to select the appropriate parameters.After the assembly of the motor is completed,the speed and stability of the laser displacement sensor are tested.Finally,the motor and ultrasonic transducer are assembled and scanned and tested to test the imaging performance of the probe and verify the feasibility of the piezoelectric motor front.After the optimization and analysis of finite elements,a miniature piezoelectric motor with a diameter of 1mm and a total length of 10mm was assembled.The motor reaches a maximum speed of 6450rpm at 20Vp-p,which meets the basic image require-ment that the speed of the motor should reach up to 1800rpm.In addition,the motor also has the characteristics of stable and low power consumption.Scanning tests with ultra-sonic transducer clearly reflect the shape of the original obj ect,indicating the feasibility of placing this miniature piezoelectric motor on the front of the ultrasonic probe.