W. M. Keck Foundation High-Field MRI Laboratory-Advanced Imaging Research Center, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA.
Radiology. 2011 Nov;261(2):394-403. doi: 10.1148/radiol.11102413. Epub 2011 Aug 9.
To assess the accuracy of the shutter-speed approach compared with standard approach dynamic contrast material-enhanced magnetic resonance (MR) imaging pharmacokinetic analysis for breast cancer diagnosis.
This study was approved by the institutional review board and was HIPAA compliant. Informed consent was obtained from 89 high-risk women (age range, 28-83 years) who had 92 suspicious lesions with negative findings at mammography (but visible at MR imaging). Each underwent a research dynamic contrast-enhanced MR imaging examination just prior to a clinical MR imaging-guided interventional procedure. Tumor region of interest (ROI) averaged and (for some) pixel-by-pixel dynamic contrast-enhanced time-course data, together with mean arterial input function, were subjected to serial standard and shutter-speed approach analyses to extract pharmacokinetic parameters, including rate constant for passive contrast reagent transfer between plasma and interstitium (K(trans)) and interstitial space volume fraction, or v(e). Pathologic findings were used as reference standards. Diagnostic accuracy was assessed with receiver operating characteristic analyses.
The pathologic analyses revealed 20 malignant and 72 benign lesions. Positive predictive value of the institutional clinical breast MR imaging protocol was 22%. At 100% sensitivity, ROI-averaged shutter-speed approach K(trans) had significantly (P = .008) higher diagnostic specificity than standard approach K(trans): 86.1% versus 77.8%. The difference in the ROI-averaged K(trans) parameter value, or ΔK(trans) (≡ K(trans) [shutter-speed approach] - K(trans) [standard approach]), had even higher specificity (88.9%). Combined use of ROI analysis and pixel-by-pixel mapping of ΔK(trans) achieved 98.6% specificity at 100% sensitivity.
The use of the shutter-speed dynamic contrast-enhanced MR imaging method has the potential to improve breast cancer diagnostic accuracy and reduce putatively unnecessary biopsy procedures that yield benign pathologic findings.
http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11102413/-/DC1.
评估快门速度法与标准方法动态对比增强磁共振成像（MR）成像药代动力学分析在乳腺癌诊断中的准确性。
本研究经机构审查委员会批准，并符合 HIPAA 规定。对 89 名高危女性（年龄 28-83 岁）进行了研究，这些女性均有 92 个可疑病变，在乳腺 X 线摄影（但在 MR 成像中可见）中为阴性。每位患者在临床 MR 成像引导介入治疗前均接受了研究性动态对比增强 MR 成像检查。对肿瘤感兴趣区（ROI）平均值和（部分）像素的动态对比增强时间过程数据，以及平均动脉输入功能，进行了连续的标准和快门速度方法分析，以提取药代动力学参数，包括血浆与间质之间被动对比剂转移的速率常数（K(trans))和间质空间体积分数或 v(e)。病理发现被用作参考标准。使用受试者工作特征分析评估诊断准确性。
病理分析显示 20 个恶性病变和 72 个良性病变。机构临床乳腺 MR 成像方案的阳性预测值为 22%。在 100%的灵敏度下，ROI 平均快门速度方法 K(trans)的诊断特异性明显高于标准方法 K(trans)：86.1%比 77.8%。ROI 平均 K(trans)参数值或 ΔK(trans)（≡ K(trans) [快门速度法] - K(trans) [标准法]）的差异具有更高的特异性（88.9%）。ROI 分析与 ΔK(trans)的像素映射相结合，在 100%的灵敏度下实现了 98.6%的特异性。
使用快门速度动态对比增强磁共振成像方法有可能提高乳腺癌诊断准确性，并减少可能导致良性病理发现的不必要的活检程序。
http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11102413/-/DC1.
