LeFree M T, Simon S B, Mancini G B, Bates E R, Vogel R A
Cardiology Section, Veterans Administration Medical Center, Ann Arbor, MI 48105.
Invest Radiol. 1988 Mar;23(3):176-83. doi: 10.1097/00004424-198803000-00004.
To assess potential differences in the intrinsic properties of image recording media and their impact on quantitative coronary arteriography, we used an automatic quantitative arteriography computer program to analyze cine film and digital radiographic images of a radiographic arterial phantom. The phantom consisted of a lucite plate with precision-drilled lumena ranging from 0.5 to 5.0 mm in diameter. Film images were digitized at 2048 X 2048 pixel resolution, and digital radiographic images were acquired at 512 X 512 and 1024 X 1024 resolution. Arterial geometric diameter, percent diameter stenosis, densitometric relative cross-sectional area, and densitometric percent area stenosis were measured. All three techniques were equivalent in measuring diameters with a high degree of overall accuracy (R greater than .992). All methods overestimated diameters below 1.0 mm. Both 512 X 512 and 1024 X 1024 digital images were superior to film for densitometric measurement of relative area (R = .995 vs. R = .940, P = .0032). We conclude that automated analysis of digital radiographic images yields results that are similar in geometric precision but greater in densitometric precision than film analysis.
为评估图像记录介质的内在特性及其对定量冠状动脉造影的潜在影响，我们使用自动定量动脉造影计算机程序来分析一个放射状动脉模型的电影胶片和数字射线图像。该模型由一块有机玻璃平板组成，其上有直径从0.5到5.0毫米的精密钻孔管腔。胶片图像以2048×2048像素分辨率进行数字化处理，数字射线图像则分别以512×512和1024×1024分辨率采集。测量了动脉几何直径、直径狭窄百分比、密度测定相对横截面积以及密度测定面积狭窄百分比。所有这三种技术在测量直径方面总体精度都很高（R大于0.992），且效果相当。所有方法都高估了直径小于1.0毫米的情况。对于相对面积的密度测定，512×512和1024×1024数字图像均优于胶片（R分别为0.995和0.940，P = 0.0032）。我们得出结论，数字射线图像的自动分析所产生的结果在几何精度上相似，但在密度测定精度上比胶片分析更高。
