Software Development And Algorithm Research Of Dual Energy X-ray Bone Densitometer

With the progress of society,the rapid development of medical technology,and the general extension of human life,the whole world will face severe challenges in the process of population aging.Many medical problems have been conquered with the efforts of the whole world,but there are still many problems that have not been conquered threatening human beings all over the world,especially some chronic diseases.Although people pay special attention to their health status,they often choose to ignore some early symptoms when they do not affect people's normal production and life due to the problems of work and time.Osteoporosis is the representative of this kind of disease.Osteoporosis is a kind of systemic osteopathy.The patients suffer from systemic pain,the activities of back and waist are limited,and the risk of fracture is increased.Bone loss has begun to occur since the age of 40.In the early stage of bone loss,people can not feel the changes of their bodies at all.Only in the late stage of bone loss,when they have osteoporosis,the osteoporotic fracture will seriously threaten people's health and living standards.It is precisely because of the long development process of osteoporosis that people do not pay attention to.People who care about osteoporosis are generally hospital doctors,relevant scholars,patients with osteoporosis and a few young people.Osteoporosis is a kind of disease which is ignored by ordinary people and seriously affects people's life.At the same time,the prevalence of osteoporosis in women is much higher than that in men.Women should pay more attention to their own bone health.This paper introduces the physical principle of dual energy ray,the photoelectric effect of the interaction between X-ray and matter,Compton effect and electron pair effect.The attenuation of X-ray in human body,single energy X-ray and dual energy X-ray.The measurement methods of BMD include X-ray photography,photon absorption,ultrasound,quantitative CT and dual energy X-ray absorption.In order to design the software of dual energy X-ray bone densitometer for radius and ulna,it is required that the software has simple workflow and clear operation flow.In this study,the dual energy X-ray is produced by the high-low energy switching method,and the image of radius and ulna is acquired quickly by the cone beam X-ray scanning method.The software design includes X-ray exposure control,data acquisition,image segmentation of radius and ulna and bone density calculation algorithm.Exposure control sends exposure command and data to dual energy X-ray bone densitometer through serial communication.Data acquisition is to read the image of data acquisition card.Using Haar like cascade classifier to locate the position ofradius and ulna in the image,the recognition rate of Haar like cascade classifier is 96.1%.Canny edge detection technology was used to segment the image of radius and ulna.The accuracy of segmentation was 96.728%.The BMD was calculated by quadric fitting.Through the accuracy test,the linear correlation coefficient of phantom test is more than99%,and the CV value of single day repeatability and multi day repeatability is less than 1%.