Liehn J C, Hannequin P, Amico S, Deschildre A, Elaerts J, Bajolet A, Valeyre J L
Eur J Nucl Med. 1984;9(10):446-52. doi: 10.1007/BF00563167.
A new method for analyzing cardiac parametric images is introduced. Its original feature is the representation of local heart motion in a polar coordinate plane which makes the integration of the information contained in three parametric images possible. These images are calculated using first harmonic Fourier filtering and are the maximum volume image, the local ejection fraction image, and the phase image. The last two parametric images are considered as the complex ejection fraction parametric image which is described by a 2D distribution in the complex plane. This method is a generalized 2D version of the well-known phase histogram method. By segmenting the complex plane in which this representation is made, four indexes are defined called the index of hypokinesia, the index of asynergy, the mean phase shift in asynergic regions, and the mean ejection fraction in asynergic regions. The values of those indexes are used to assess the degree and extent of regional wall motion abnormalities. An automated classification as normal, hypokinetic, akinetic, slightly dyskinetic, and strongly dyskinetic made on the basis of the values of those indexes has been compared with a visual classification made by three observers in 219 studies. ROC curves show a good agreement between the automated and visual methods. This new method provides an efficient means of automatically classifying cardiac studies.
介绍了一种分析心脏参数图像的新方法。其独特之处在于在极坐标平面中表示局部心脏运动，这使得整合三个参数图像中包含的信息成为可能。这些图像是使用一次谐波傅里叶滤波计算得出的，分别是最大容积图像、局部射血分数图像和相位图像。后两个参数图像被视为复射血分数参数图像，它由复平面中的二维分布描述。该方法是著名的相位直方图方法的广义二维版本。通过划分进行这种表示的复平面，定义了四个指标，分别称为运动减弱指数、运动失调指数、运动失调区域的平均相移和运动失调区域的平均射血分数。这些指标的值用于评估局部室壁运动异常的程度和范围。基于这些指标的值进行的正常、运动减弱、运动不能、轻度运动障碍和重度运动障碍的自动分类，已与219项研究中三位观察者进行的视觉分类进行了比较。ROC曲线表明自动方法和视觉方法之间具有良好的一致性。这种新方法为心脏研究的自动分类提供了一种有效的手段。
