School of Dentistry and Health Sciences, Faculty of Science, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
Discipline of Medical Radiation Sciences, Faculty of Health Sciences, The University of Sydney Cumberland Campus, 75 East St, Lidcombe, NSW 2141, Australia.
Eur J Radiol. 2018 Mar;100:76-84. doi: 10.1016/j.ejrad.2018.01.004. Epub 2018 Jan 4.
The aim of this study is to determine the clinical rates of the demonstration of the inframammary angle (IMA) on the mediolateral oblique (MLO) view of the breast on digital mammograms and to compare the outcomes with current accreditation standards for compliance. Relationships between the IMA, age, the posterior nipple line (PNL) and compressed breast thickness will be identified and the study outcomes validated using appropriate analyses of inter-reader and inter-rater reliability and variability. Differences in left versus right data were also investigated.
A quantitative retrospective study of 2270 randomly selected paired digital mammograms performed by BreastScreen NSW was undertaken. Data was collected by direct measurement and visual analysis. Intra-class correlation analyses were used to evaluate inter- and intra-rater reliability.
The IMA was demonstrated on 52.4% of individual and 42.6% of paired mammograms. A linear relationship was found between the posterior nipple line (PNL) and age (p-value <0.001). The PNL was predicted to increase by 0.48 mm for every one year increment in age. The odds of demonstrating the IMA reduced by 2% for every one year increase in age (p-value = 0.001); are 0.4% higher for every 1 mm increase in PNL (p-value = 0.001) and 1.6% lower for every 1 mm increase in compressed breast thickness, (p-value<0.001). There was high inter- and intra-rater reliability for the PNL while there was 100% agreement for the demonstration of the IMA.
Analysis of the demonstration of the IMA indicates clinically achievable rates (42.6%) well below that required for compliance (50%-75%) to known worldwide accreditation standards for screening mammography. These standards should be aligned to the reported evidence base. Visualisation of the IMA is impacted negatively by increasing age and compressed breast thickness but positively by breast size (PNL).
本研究旨在确定数字化乳腺钼靶摄影中乳房侧斜位（MLO）上显示内下界（IMA）的临床率，并与当前的符合率认证标准进行比较。确定 IMA 与年龄、后乳头线（PNL）和压缩乳腺厚度之间的关系，并使用适当的读者间和评分者间可靠性和可变性分析来验证研究结果。还研究了左右数据之间的差异。
对新南威尔士州乳腺癌筛查中心进行的 2270 例随机选择的数字化乳腺钼靶摄影配对进行定量回顾性研究。数据通过直接测量和视觉分析收集。使用组内相关分析评估读者间和评分者间的可靠性。
在个体和配对乳腺钼靶摄影中，IMA 分别显示在 52.4%和 42.6%的病例中。在后乳头线（PNL）和年龄之间发现了线性关系（p 值<0.001）。年龄每增加 1 岁，PNL 预计增加 0.48 mm。年龄每增加 1 岁，IMA 显示的几率降低 2%（p 值=0.001）；PNL 每增加 1 mm，几率增加 0.4%（p 值=0.001），压缩乳腺厚度每增加 1 mm，几率降低 1.6%（p 值<0.001）。PNL 的读者间和评分者间可靠性较高，而 IMA 的显示则有 100%的一致性。
对 IMA 显示的分析表明，临床上可达到的比率（42.6%）远低于全球公认的筛查乳腺钼靶摄影符合率认证标准（50%-75%）。这些标准应与报告的证据基础相一致。IMA 的可视化受年龄和压缩乳腺厚度的增加以及乳房大小（PNL）的增加而受到负面影响。
