Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
J Appl Clin Med Phys. 2020 Nov;21(11):188-194. doi: 10.1002/acm2.13010. Epub 2020 Oct 22.
To assess the diagnostic performance of breast magnetic resonance (MR) imaging as a function of gadolinium contrast dose using a retrospective reader study.
IRB approval was obtained prior to the start of this study and was HIPAA compliant. One-hundred and fifty MR breast examinations were included that were acquired between January 2001 and December 2006. Seventy-five patients received contrast doses (gadopentetate dimeglumine) by weight of 0.10 mmol/kg and 75 patients were imaged using fixed volumes of 20 ml. The images were assessed by two radiologists with performance calculated for each reader as well as a combined assessment. Dose response was measured by comparing performance between cases binned by dose: <=0.10; >0.10; and >0.13 mmol/kg. Statistical significance was calculated using a one-sided Z-test for differences in proportions with interobserver agreement calculated using Cohen's kappa statistics.
In the combined reader assessment with equivocal lesions classified as negative, sensitivity rose from 66% (19/29) to 92% (24/26, P < 0.01) and 95% (18/19, P < 0.01) with the specificity also increasing from 65% (32/49) to 87% (40/46, P < 0.01) and 86% (32/37, P = 0.01) corresponding to doses <=0.10, >0.10, >0.13 mmol/kg. With equivocal lesions classified as positive, sensitivity rose from 79% (23/29) to 92% (24/26, P < 0.10) and 95% (18/19, P < 0.10) Specificity also increased from 53% (26/49) to 72% (33/46, P < 0.05) and 70% (26/37, P = 0.05) with increasing dose. Interobserver agreement also improved at the higher doses.
使用回顾性读者研究评估乳腺磁共振（MR）成像作为对比剂量函数的诊断性能。
本研究获得了机构审查委员会的批准，并符合 HIPAA 规定。共纳入 2001 年 1 月至 2006 年 12 月期间进行的 150 次 MR 乳腺检查。75 例患者按体重接受 0.10mmol/kg 的对比剂剂量（钆喷替酸二甲葡胺），75 例患者接受固定体积 20ml 的造影剂。由两位放射科医生评估图像，每位读者的表现以及联合评估的结果均进行计算。通过比较按剂量分组的病例（<=0.10；>0.10；和>0.13mmol/kg）之间的性能来衡量剂量反应。使用单侧 Z 检验计算差异的统计学意义，并使用 Cohen's kappa 统计计算观察者间一致性。
在联合读者评估中，将可疑病变分类为阴性时，灵敏度从 66%（29 例中的 19 例）升高至 92%（26 例中的 24 例，P<0.01）和 95%（19 例中的 18 例，P<0.01），特异性也从 65%（49 例中的 32 例）升高至 87%（46 例中的 40 例，P<0.01）和 86%（37 例中的 32 例，P=0.01），相应剂量为<=0.10、>0.10、>0.13mmol/kg。将可疑病变分类为阳性时，灵敏度从 79%（29 例中的 23 例）升高至 92%（26 例中的 24 例，P<0.10）和 95%（19 例中的 18 例，P<0.10），特异性也从 53%（49 例中的 26 例）升高至 72%（46 例中的 33 例，P<0.05）和 70%（37 例中的 26 例，P=0.05），剂量增加。观察者间一致性也在较高剂量下得到改善。
