Motion-guided segmentation for cine DENSE MRI.
Motion-guided segmentation for cine DENSE MRI.
复制标题
DOI：
10.1016/j.media.2008.06.016
复制
发表时间：
2009-02
影响因子：
10.9
通讯作者：
Epstein FH
中科院分区：
文献类型：
--
作者：
Spottiswoode BS;Zhong X;Lorenz CH;Mayosi BM;Meintjes EM;Epstein FH
定义心肌轮廓通常是动态心脏MRI图像分析中最耗时的部分。受激回波位移编码（DENSE）是一种定量MRI技术，可将组织位移编码到复杂MRI图像的相位中。Cine DENSE提供了这些图像的时间序列，从而促进了心肌运动学的非侵入性研究。需要在电影DENSE图像上的每帧定义心外膜和心内膜轮廓，以量化作为时间函数的区域位移和应变。这项工作提出了一种可靠和有效的二维半自动分割技术，使用编码的运动，通过时间投影手动定义的感兴趣区域。然后可以容易地提取每个心脏相位的轮廓。该方法具有几个优点，包括：1.参数是基于实际的生理限制，2.针对前几个心动时相计算轮廓，在前几个心动时相难以在视觉上区分血液和心肌;以及3.该方法与所描绘的组织的形状无关，并且可以应用于短轴或长轴视图以及任意感兴趣区域。将运动引导轮廓与6个常规和6个切片跟踪的心室中短轴电影DENSE数据集的手动轮廓进行比较。使用分割误差的面积测量，分割算法的准确性被证明与观察者间变异性相似。此外，径向分割误差度量引入短轴数据。切片跟踪和常规电影DENSE的平均径向心外膜分割误差分别为0.36 ± 0.08和0.40 ± 0.10像素，切片跟踪和常规电影DENSE的平均径向内膜分割误差分别为0.46 ± 0.12和0.46 ± 0.16像素。运动引导分割采用DENSE MRI固有的位移编码相移，在剩余的心脏相位中准确传播一组预定义轮廓。
Defining myocardial contours is often the most time consuming portion of dynamic cardiac MRI image analysis. Displacement encoding with stimulated echoes (DENSE) is a quantitative MRI technique that encodes tissue displacement into the phase of the complex MRI images. Cine DENSE provides a time series of these images, thus facilitating the non-invasive study of myocardial kinematics. Epicardial and endocardial contours need to be defined at each frame on cine DENSE images for the quantification of regional displacement and strain as a function of time. This work presents a reliable and effective two dimensional semi-automated segmentation technique that uses the encoded motion to project a manually defined region of interest through time. Contours can then easily be extracted for each cardiac phase. This method boasts several advantages, including, 1. parameters are based on practical physiological limits, 2. contours are calculated for the first few cardiac phases, where it is difficult to visually distinguish blood from myocardium, and 3. the method is independent of the shape of the tissue delineated and can be applied to short- or long-axis views, and on arbitrary regions of interest. Motion-guided contours were compared to manual contours for six conventional and six slice-followed mid-ventricular short-axis cine DENSE datasets. Using an area measure of segmentation error, the accuracy of the segmentation algorithm was shown to be similar to inter-observer variability. In addition, a radial segmentation error metric was introduced for short-axis data. The average radial epicardial segmentation error was 0.36±0.08 and 0.40±0.10 pixels for slice followed and conventional cine DENSE, respectively, and the average radial endocardial segmentation error was 0.46±0.12 and 0.46±0.16 pixels for slice following and conventional cine DENSE, respectively. Motion-guided segmentation employs the displacement-encoded phase shifts intrinsic to DENSE MRI to accurately propagate a single set of pre-defined contours throughout the remaining cardiac phases.
登录
查看更多内容
影响因子：
19.7
作者：
Moore, CC;Lugo-Olivieri, CH;Zerhouni, EA
通讯作者：
Zerhouni, EA
DOI：
10.1152/ajpheart.00632.2004
发表时间：
2005-03-01
影响因子：
4.8
作者：
Gilson, WD;Yang, ZQ;Epstein, FH
通讯作者：
Epstein, FH
DOI：
10.1007/978-3-540-39899-8_63
发表时间：
2003-01-01
期刊：
MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION - MICCAI 2003, PT 1
影响因子：
--
作者：
Montillo, A;Metaxas, D;Axel, L
通讯作者：
Axel, L
影响因子：
19.7
作者：
AXEL, L;DOUGHERTY, L
通讯作者：
DOUGHERTY, L
影响因子：
19.5
作者：
KASS, M;WITKIN, A;TERZOPOULOS, D
通讯作者：
TERZOPOULOS, D