Diffusion Weighted Breast MR Imaging for Screening Women with Dense Breasts

描述（由申请人提供）：扩散加权成像（DWI）有可能成为超声的安全、经济有效的替代方法，作为乳腺X线摄影的补充程序，用于筛查40%-50%的致密乳腺女性，以识别可疑乳腺病变的女性。研究人员已经开发了两种正在申请专利的方法，用于提高使用（DWI）检测乳腺癌的灵敏度：（1）分析病变边界的ADC梯度，以及（2）增强扩散图像以提高病变与背景组织的区分。在I期研究中，新方法成功地检测和区分了很高比例的乳腺病变，没有因为成像问题或患者运动而拒绝任何病例。在第二阶段，研究人员将使用新的方法开发一个原型计算机辅助诊断（CAD）系统，并将通过读者研究评估性能。 DWI检测乳腺癌的主要指标是表观扩散系数（ADC）。其他弥散测量需要弥散张量成像（DTI），这是一种成像程序，需要两倍于DWI的时间，并且更难以证明成本合理。使用标准的方法，ADC有两个关键的缺点，低灵敏度和高拒绝率，由于成像问题和患者的运动，这阻碍了临床使用的DWI乳腺癌检测。第一阶段开发的两种创新方法提高了灵敏度，在第一阶段可行性研究中的拒绝率为零。 乳房X光检查和超声波检查都漏诊了高密度乳房妇女中相当大比例的乳腺癌。动态对比增强（DCE）MRI筛查具有高灵敏度，但不推荐用于筛查低或中度乳腺癌风险的女性。美国癌症协会建议当女性的风险高于20%时进行乳腺癌筛查，当高乳腺密度是唯一的风险因素时，这一阈值不会达到。该项目的长期目标是开发一种临床和商业上可行的CAD系统，用于评估DWI图像，当与乳腺X射线摄影术结合使用时，能够识别乳腺癌风险大于20% ACS阈值的致密乳房女性，随访DCE筛查的成本合理。

DESCRIPTION (provided by applicant): Diffusion Weighted Imaging (DWI) has the potential for being a safe, cost-effective alternative to ultrasound as a supplemental procedure to mammography for screening the 40%-50% of women with dense breasts to identify women who have suspicious breasts lesions. The investigators have developed two patent-pending methods for improving sensitivity in detection of breast cancer using (DWI): (1) Analyzing ADC gradient at the lesion border, and (2) Enhancing diffusion images to improve differentiation of lesion from background tissue. In the Phase I study, the novel methodologies successfully detected and discriminated a high percentage of breast lesions, without rejecting any cases because of imaging problems or patient motion. In Phase II, the investigators will develop a prototype computer-aided-diagnosis (CAD) system using the novel methodologies and will evaluate performance with a reader study. The primary measurement for detecting breast cancer in DWI is Apparent Diffusion Coefficient (ADC). Other measures of diffusion require Diffusion Tensor Imaging (DTI), an imaging procedure that takes twice as long as DWI and is more difficult to cost-justify. Using standard methodologies, ADC has two critical shortcomings, low sensitivity and high rejection rate due to imaging problems and patient motion, which hinder clinical use of DWI for breast cancer detection. The two innovative methodologies developed in Phase I improved sensitivity and had zero rejection rate in the Phase I feasibility study. Both mammography and ultrasound miss a significant percentage of breast cancers in women with dense breasts. Dynamic Contrast Enhanced (DCE) MRI screening has high sensitivity, but is not recommended for screening women who have a low or moderate risk of breast cancer. The American Cancer Society recommends DCE for breast cancer screening when a women's risk is higher than 20%, a threshold that is not met when high breast density is the only risk factor. The long-range goal of this project is to develop a clinically and commercially viable CAD system for evaluating DWI images which, when used in conjunction with mammography, is able to identify those women with dense breasts who have a breast-cancer risk greater than the 20% ACS threshold for which follow-up DCE screening is cost-justified.