Bazille A, Guttman M A, McVeigh E R, Zerhouni E A
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205.
Invest Radiol. 1994 Apr;29(4):427-33. doi: 10.1097/00004424-199404000-00008.
Accurate image segmentation is essential for the study of mechanical properties of the myocardium by tagged magnetic resonance imaging (MRI). The relative accuracy of three methods of segmentation of myocardial borders and tags and their impact on myocardial strain calculations were evaluated.
Radially tagged, spin-echo magnetic resonance (MR) images of dog hearts were segmented manually, automatically, and semiautomatically. The variability of segmentation methods was separately determined for myocardial contours and tags. Error propagation assessment for strain calculation was estimated.
The variability of the segmentation of the contours was five times greater than that of the tags. The error propagation is nonuniform in all directions, maximal for the radial component of strain.
Errors in the segmentation of myocardial contours are significantly greater than those of the tags. Strain calculations should be based solely on segmentation of MR tags to avoid significant errors, particularly in radial strain estimates.
准确的图像分割对于通过标记磁共振成像(MRI)研究心肌力学特性至关重要。评估了三种心肌边界和标记分割方法的相对准确性及其对心肌应变计算的影响。
对犬心脏的径向标记自旋回波磁共振(MR)图像进行手动、自动和半自动分割。分别确定心肌轮廓和标记分割方法的变异性。估计应变计算的误差传播评估。
轮廓分割的变异性比标记分割的变异性大五倍。误差传播在所有方向上不均匀,在应变的径向分量上最大。
心肌轮廓分割中的误差明显大于标记分割中的误差。应变计算应仅基于MR标记的分割,以避免显著误差,特别是在径向应变估计中。