The Research Of Automatic Tracking Of Myocardial Motion Based On M-mode Ultrasonic

Currently, heart disease is common disease and frequently-occurring disease. It is harm to people’s health and threaten people’s life. With the aging population in our country, there is an increasing tendency in the incidence of cardiovascular disease and death rate. The diagnosis of cardiovascular disease were significantly improved by widely use of medical imaging technology. It has an important reference value in the diagnosis of cardiovascular disease by use of ultrasonic cardiogram. Ultrasonic diagnosis has the characteristics of simple operation, low cost and no ionizing radiation damage to human body.In the study of echocardiography, cardiac motion trajectory is the research focus in e valuation of myocardium. The key of researching ultrasonic cardiogram is the method of tracking of Local Myocardial Motion. First, scaning heart to get ultrasonic signals by means of M-mode ultrasonic. Then.receiving Instantaneous phase change of singal by a series of transforming about ultrasonic. Thus, utilizing instantaneous velocity model to track myocardial motion trajectory get through calculating instantaneous velocity of each sample in cardiac muscle. In order to get closer to the real myocardial motion, the paper was divided into the following two parts:1.Putting forward the method of automatically detection of one heart-beat period based on M-mode. Determining a cardiac cycle by use of correlation analysis method according to the periodic law of heartbeat and phase change of ultrasonic at different time. The experiment of automatically determinating cardiac cycle was carried out via clinical data of 13 cases of M-mode ultrasonic. The results show that it has high accuracy, can replace the doctor’s manual operation and can provide reliable parameters for the tracking myocardial trajectory take advantage of correlation analysis comparing to the results of doctor’s manual operation.2.Setting up the two dimensional dynamic programming model of tracking myocardial trajectory. Joining the contractile properties between myocardial layer on the basis of one-dimensional dynamic programming method. The two dimensional dynamic programming model not only has the global optimality of one-dimensional dynamic programming, reduce the influence of the spots in ultrasonic signal and noise, but aslo make the trajectory tracking result conforms to the real value. Conducting an experiment of the clinical data of 26 groups of M-mode ultrasonic. It were 13 ventricular septum datas and 13 left ventricular posterior wall datas respectively. Tracking myocardial motion trajectory take use of two-dimensional dynamic model method, one dimensional dynamic programming methods, and the doctor’s manual operation respectively. Start points of tracking stay the same. It proved that the proposed method has high accuracy, the ability of replacing the manual operation, can reduce the tracking error, improve the efficiency of the diagnosis of cardiovascular diseas compared to two dimensional dynamic programming method and experienced doctor’s manual operation results. In addition, It proved that the quality and accuracy of myocardial motion curve obtained form two dimensional dynamic programming model was better than one-dimensional dynamic programming method compared to two dimensional dynamic programming method and the traditional one-dimensional dynamic programming method.