Cardiac Ultrasound Imaging Based On Speckle Tracking Strain Analysis

Currently, cardiovascular disease has become one of the major causes of human death. In order to the image of the heart to diagnose heart disease, medical imaging technology has become an important clinical tool. Ultrasound imaging diagnostic techniques as a result of its rapid and painless to the patient has become one of the main methods. The speckle tracking technology is about two-dimensional ultrasound images, based on the best pattern-matching technology used to identify myocardial speckle tracking the movement and tracking of each frame in the image on the location of changes in mapping out the different images in the same frame trajectory of the myocardial location.This article is based on the heart of left ventricular two-dimensional ultrasound image of the movement sequence, by tracking its short-axis image speckle information, to analyze myocardial strain. The main work is divided into three parts:1. Segmentation of cardiac ultrasound images into inside and outside of the left ventricular myocardium, reflecting regional myocardial motion. In this paper, by comparing the Snake model and GVF Snake model, we can find that these two algorithms are sensitive to the initialization,and segmentation results are unsatisfactory,and the C-V model algorithm cannot achieve promising results for the gray ultrasound image in the presence of intensity inhomogenetity. This paper mainly utilizes local Gaussian density fitting energy. We propose to delineate the left ventricular myocardial area by two initial curves. The experimental results show that this method can deal with such noisy ultrasound image in the presence of inhomogeneity and noise.2. Extracting Speckle. According to the characteristics of ultrasound images, by setting a fixed-size window to traverse the entire image to compare pixel gray value, we can use the extreme points of the region to mark the location of spots.3. Speckle tracking and calculating strain. Registration to be spotted through the matching of corresponding points, which can be time-varying speckle images in different changes of position, displacement can be calculated. According to elasticity of the displacement and strain in the relationship, we can calculate strain. So that we can get diastolic and systolic myocardial's movements at the time.