de Groot J E, Hopman I G M, van Lier M G J T B, Branderhorst W, Grimbergen C A, den Heeten G J
Sigmascreening, Meibergdreef 45, 1105 BA, Amsterdam, The Netherlands.
University of Amsterdam, The Netherlands.
Eur J Radiol. 2017 Jan;86:289-295. doi: 10.1016/j.ejrad.2016.11.030. Epub 2016 Nov 28.
A recent technological development allows pressure-standardised mammography by personalizing the compression force to the breast size and firmness. The technique has been shown to reduce pain and compression variability between consecutive exams, but also results in a slightly thicker compressed breast during exposure. This raises the question whether visibility, contrast and sharpness of lesions are affected?
Four experienced radiologists compared 188 stable lesions and structures including (clusters of) calcifications, (oil) cysts and lymph nodes that were visible in mammograms obtained in 2009 with a pain-tolerance limited 18 daN target force compression protocol, and in 2014/2015 obtained with a 10kPa (75mmHg) pressure-standardised compression protocol. Observers were blinded for all DICOM metadata and rated which of the randomly ordered, side by side presented images had better lesion visibility, contrast and sharpness, or whether they saw no difference. They also indicated which overall image they preferred, if any, and whether the non-preferred image was still adequate. Statistical non-inferiority is concluded when the lower limit of the 95% confidence interval of the 4-rater averaged 'new protocol better' proportions exceed the non-inferiority limit of 0.463.
In 2014/2015, the compressions were significantly milder, with on average 17% (mediolateral oblique) to 29% (craniocaudal) lower forces. Breasts remained on average 2.4% (1.4mm) thicker. Dose was significantly lower (6.5%), which is explained by glandular atrophy. The 95% confidence interval lower limits are 0.479 for visibility, 0.473 for contrast, 0.488 for sharpness and 0.486 for preference, all exceeding the non-inferiority limit. Of the 60 non-preferred mammograms, multiple observers found only five to be inadequate: 4 obtained with the force protocol and 1 with the pressure protocol.
Pain-reduced mammography with 10kPa pressure-standardised compression has non-inferior visibility, contrast and sharpness for stable lesions compared to pain-tolerance limited 18daN target force compression.
最近的一项技术发展使得通过根据乳房大小和硬度个性化施加压迫力来实现压力标准化乳腺摄影。该技术已被证明可减轻疼痛并减少连续检查之间的压迫差异，但在曝光期间也会导致受压乳房略厚。这就引发了一个问题，即病变的可视性、对比度和清晰度是否会受到影响？
四位经验丰富的放射科医生比较了188个稳定的病变和结构，包括（簇状）钙化、（油）囊肿和淋巴结，这些在2009年采用疼痛耐受限度为18daN目标力压迫方案获得的乳腺造影片中可见，以及在2014/2015年采用10kPa（75mmHg）压力标准化压迫方案获得的乳腺造影片中可见。观察者对所有DICOM元数据不知情，并对随机排序、并排呈现的图像中哪张具有更好的病变可视性、对比度和清晰度进行评分，或者他们是否认为没有差异。他们还指出他们更喜欢哪张整体图像（如果有的话），以及不喜欢的图像是否仍然足够。当四位评分者平均“新方案更好”比例的95%置信区间下限超过非劣效性界限0.463时，得出统计非劣效性结论。
在2014/2015年，压迫明显更轻，平均力量降低了17%（内外斜位）至29%（头尾位）。乳房平均厚2.4%（1.4毫米）。剂量显著降低（6.5%），这是由腺体萎缩所致。可视性的95%置信区间下限为0.479，对比度为0.473，清晰度为0.488，偏好度为0.486，均超过非劣效性界限。在60张不喜欢的乳腺造影片中，多位观察者仅发现5张不合格：4张采用力量方案获得，1张采用压力方案获得。
与疼痛耐受限度为18daN目标力压迫相比，采用10kPa压力标准化压迫的减轻疼痛的乳腺摄影对稳定病变具有非劣效的可视性、对比度和清晰度。
