Seattle Cancer Care Alliance, Department of Radiology, 825 Eastlake Avenue, Seattle, WA 98109, USA.
Acad Radiol. 2010 Jun;17(6):791-4. doi: 10.1016/j.acra.2010.02.007.
We undertook this study to determine whether differences in detector-lesion distance resulted in appreciable effects on digital magnification mammography performance as measured using the American College of Radiology (ACR) mammography phantom and a line pair test pattern.
Images of the standard 42-mm thick standard ACR mammography phantom with a wax insert on one side containing simulated fibers, calcifications, and masses were obtained on a Senographe Essential digital mammography system with the phantom in upright and inverted positions. The process was repeated with a line pair test pattern for measuring resolution. All images were obtained in contact mode, and with 1.5x and 1.8x magnification, and evaluated on a GE PACS monitor.
Overall, changing lesion-detector distance using standard versus inverted positioning did not appreciably increase the number of objects seen on the ACR phantom under all modes. No greater than one line pair difference was seen in standard versus inverted positioning. At 1.8x magnification mode, no difference was detected in line pair resolution with a change in positioning.
Differences in lesion-detector distance as modeled using both the ACR mammography phantom and a line pair test pattern did not make an appreciable difference in digital magnification mammography performance.
我们进行这项研究是为了确定探测器-病变距离的差异是否会对数字放大乳房 X 线摄影性能产生明显影响，该性能是使用美国放射学院（ACR）乳房 X 线摄影体模和线对测试图案来测量的。
使用 Senographe Essential 数字乳房 X 线摄影系统，在体模直立和倒置位置，对一侧带有模拟纤维、钙化和肿块的标准 42 毫米厚的标准 ACR 乳房 X 线摄影体模上的图像进行了获取。该过程重复进行了线对测试图案以测量分辨率。所有图像均在接触模式下获得，并使用 1.5x 和 1.8x 放大率，在 GE PACS 监视器上进行评估。
总体而言，使用标准与倒置定位改变病变-探测器距离并没有明显增加 ACR 体模在所有模式下可见的物体数量。在标准与倒置定位之间，线对差异不超过一个。在 1.8x 放大模式下，改变定位时，对线对分辨率没有检测到差异。
使用 ACR 乳房 X 线摄影体模和线对测试图案模拟的病变-探测器距离差异，对数字放大乳房 X 线摄影性能没有明显影响。
