Bonard P, Tremblay G, LeBlanc A R, Bertrand M, Roberge F A
Cathet Cardiovasc Diagn. 1978;4(2):111-26.
Some of the problems associated with the precise evaluation of left ventricular volumes from angiographic images are due to the magnification and distortion of the pictures obtained from X-ray equipment. Magnification errors can be evaluated easily but the distortion (due to pincushion effect) are more difficult to measure. A mathematical method is proposed for a complete point-by-point correction of errors due to magnification and X-ray distortion. This method is applicable to most currently used angiographic equipment. Since more and more angiographic images are processed with local or remote digital computers, the applicability of the proposed technique becomes realistic. Results from this study show that a 5-30% overestimation of usual geometric ventricular parameters is encountered if no correction is made for distortion. End-diastolic measurements are more affected than end-systolic ones because of the greater degree of spherical distortion at the periphery of the picture area.
从血管造影图像精确评估左心室容积存在一些问题，这是由于X射线设备所获图像的放大和失真所致。放大误差易于评估，但失真（由于枕形效应）更难测量。本文提出一种数学方法，用于对放大和X射线失真引起的误差进行完整的逐点校正。该方法适用于目前大多数使用的血管造影设备。由于越来越多的血管造影图像是由本地或远程数字计算机处理的，所以所提技术的适用性变得切实可行。本研究结果表明，如果不校正失真，通常的几何心室参数会被高估5%-30%。舒张末期测量比收缩末期测量受影响更大，因为图像区域周边的球形失真程度更大。
