A Catheter Probe For Photoacoustic Endoscopic Imaging Based On Collinear Design

As a new generation of medical imaging technology,photoacoustic imaging is transmitted through pulsed laser irradiation tissue,which produces ultrasonic signals due to thermoelastic effect.Development of photoacoustic imaging endoscopic can solve the problem of the current lack of photoacoustic imaging penetration depth,endoscopic imaging is to integrate the photoacoustic imaging,to spy out of internal organs in the head imaging,due to its goal and imaging is more close to,so show enough high penetration depth.It is a novel design method to unify the laser excitation path and the ultrasonic detection path.At present,the probes in the optical acoustic endoscopic imaging system are focused probes,which are relatively simple but usually larger in size and have great limitations in practical clinical applications.The other type is non-focused probe,which usually adopts non-collinear design,although the size is small enough to meet the clinical requirements,but it does not show sufficient imaging depth.Considering the shortcomings of the above endoscopic probe,in this paper,based on the idea of collinear design developed a use photoacoustic endoscopic imaging was only about 4 mm in diameter of non-focus collinear probe,which meets the requirement of small diameter for the probe of clinical trial,and also makes up the shortcoming of the non-collinear probe imaging depth.This paper first introduces the background and significance of the study of optical acoustic endoscopy.Then the paper introduces the research status of endoscopic probe,and introduces the principle and structure of the endoscopic collinear probe.Next,the material selection and production method of collinear probe are introduced.Then a sound field simulation method is introduced to simulate the sound field and the endoscopic experiment of the collinear probe.Finally photoacoustic endoscopic imaging system are introduced in detail the hardware and software design,the image reconstruction of endoscopic imaging principle and algorithm,and the application of endoscopic probes for endoscopic imaging was introduced through a endoscopic experiment.The experimental results show that this paper successfully developed a novel non-focus probe with a diameter of 4mm for photoacoustic endoscopic imaging,and it is first implemented in research at home and abroad by the mini stepper motor drives the photoacoustic mirror finish see head inside the smallest size precision scanning;And it can realiza the maximum overlap of the excitation laser path and the ultrasonic detection path in the space.In addition,its small size is expected to be used in the internal organs such as cervical canal,blood vessel,rectum and so on.