Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
Acad Radiol. 2010 Apr;17(4):433-40. doi: 10.1016/j.acra.2009.10.020. Epub 2009 Dec 29.
Conventional mammography can not distinguish between transmitted, scattered, or refracted x-rays, thus requiring breast compression to decrease tissue depth and separate overlapping structures. Diffraction-enhanced imaging (DEI) uses monochromatic x-rays and perfect crystal diffraction to generate images with contrast based on absorption, refraction, or scatter. Because DEI possesses inherently superior contrast mechanisms, the current study assesses the effect of breast compression on lesion characteristic visibility with DEI imaging of breast specimens.
Eleven breast tissue specimens, containing a total of 21 regions of interest, were imaged by DEI uncompressed, half-compressed, or fully compressed. A fully compressed DEI image was displayed on a soft-copy mammography review workstation, next to a DEI image acquired with reduced compression, maintaining all other imaging parameters. Five breast imaging radiologists scored image quality metrics considering known lesion pathology, ranking their findings on a 7-point Likert scale.
When fully compressed DEI images were compared to those acquired with approximately a 25% difference in tissue thickness, there was no difference in scoring of lesion feature visibility. For fully compressed DEI images compared to those acquired with approximately a 50% difference in tissue thickness, across the five readers, there was a difference in scoring of lesion feature visibility. The scores for this difference in tissue thickness were significantly different at one rocking curve position and for benign lesion characterizations. These results should be verified in a larger study because when evaluating the radiologist scores overall, we detected a significant difference between the scores reported by the five radiologists.
Reducing the need for breast compression might increase patient comfort during mammography. Our results suggest that DEI may allow a reduction in compression without substantially compromising clinical image quality.
传统的乳房 X 光摄影无法区分透射、散射或折射的 X 射线，因此需要对乳房进行压缩以减少组织深度并分离重叠结构。衍射增强成像（DEI）使用单色 X 射线和完美晶体衍射，根据吸收、折射或散射生成对比度图像。由于 DEI 具有固有的优越对比度机制，因此当前的研究评估了在乳房标本的 DEI 成像中，乳房压缩对病变特征可见性的影响。
对 11 个乳房组织标本进行 DEI 成像，共包含 21 个感兴趣区域，分别在未压缩、半压缩和完全压缩状态下进行成像。完全压缩的 DEI 图像显示在软拷贝乳房 X 线摄影复查工作站上，旁边是使用减少的压缩获得的 DEI 图像，保持所有其他成像参数不变。五位乳房成像放射科医生根据已知的病变病理学考虑图像质量指标进行评分，对他们的发现进行 7 分李克特量表评分。
当完全压缩的 DEI 图像与组织厚度差异约为 25%的图像进行比较时，病变特征可见性评分没有差异。对于完全压缩的 DEI 图像与组织厚度差异约为 50%的图像进行比较，五位读者的病变特征可见性评分存在差异。在一个晃动曲线位置和良性病变特征的评分中，这种组织厚度差异的评分存在显著差异。由于当评估放射科医生的总体评分时，我们检测到五位放射科医生报告的评分之间存在显著差异，因此这些结果应在更大的研究中进行验证。
减少乳房压缩的需求可能会增加乳房 X 光摄影过程中的患者舒适度。我们的结果表明，DEI 可能允许减少压缩而不会严重影响临床图像质量。
