December 01, 2012
Press releases were sent to the medical news media for the following articles
appearing in recent issues of Radiology.
Nonmalignant Breast Lesions: ADCs of Benign and High-Risk Subtypes Assessed
as False-Positive at Dynamic Enhanced MR Imaging
Assessing apparent diffusion coefficients (ADCs) along with dynamic contrast-enhanced MR imaging features may decrease the number of avoidable false-positive findings at breast MR imaging and reduce the number of preventable biopsies, new research shows.
In the study, Sana Parsian, M.D., of the University of Washington School of Medicine, Seattle, and colleagues retrospectively reviewed lesions assessed as Breast Imaging Reporting and Data System (BI-RADS) category 4 or 5 at clinical dynamic contrast material–enhanced MR imaging that subsequently proved nonmalignant at biopsy. Researchers evaluated 175 nonmalignant breast lesions in 165 women. ADCs from diffusion-weighted (DW) imaging were calculated for each lesion and compared between subtypes and with an ADC threshold determined in a prior study to achieve 100 percent sensitivity.
Results showed that 46 percent of nonmalignant breast lesions assessed as false-positive findings at dynamic contrast-enhanced MR imaging had ADCs higher than the previously determined diagnostic threshold.
“Our findings show promise for using diffusion-weighted imaging to reduce the number of avoidable false-positive findings at breast dynamic contrast-enhanced MR imaging; improving the specificity of breast MR imaging would reduce the number of avoidable biopsies and associ-ated morbidity for the patient,” the researchers write.
Comparison of Digital Screening Mammography and Screen-Film Mammography in the Early Detection of Clinically Relevant Cancers: A Multicenter Study
In a large, population-based breast cancer screening program, digital mammography performed substantially better than screen-film mammography (SFM) in detecting ductal carcinoma in situ (DCIS) and invasive carcinoma, new research shows.
In the study, Adriana M.J. Bluekens, M.D., of the National Expert and Training Centre for Breast Cancer Screening in Nijmegen and St. Elisabeth Hospital in Tilburg, both in the Netherlands, and colleagues compared digital mammography to SFM in 1,198,493 screening mammograms performed between 2003 and 2007. Of those, 83.3 percent were SFM examinations and 12.7 percent were digital mammography examinations. Recall was indicated in 18,896 cases.
For initial screening examinations, the detection rate per 1,000 women was 5.6 with SFM and 6.8 with digital mammography. The difference in detection for subsequent screening examinations was also in favor of digital mammography, with respective rates of 5.2 and 6.1 per 1,000 women. Detection of high-grade DCIS with digital mammography was 58.5 percent, compared with 50.5 percent for SFM.
“Digital screening mammography demonstrates advantages in the early detection of breast cancer by increasing the detection of clinically relevant cancers while keeping potential overdiagnosis low,” the authors write. “This gain is largely due to enhanced depiction of microcalcifications, resulting in improved detection of both DCIS and invasive carcinoma.”
Coronary Vessel Wall 3-T MR Imaging with Time-resolved Acquisition of Phase-Sensitive Dual Inversion-Recovery (TRAPD) Technique: Initial Results in Patients with Risk Factors for Coronary Artery Disease
TIME-RESOLVED acquisition of phase-sensitive dual-inversion recovery (TRAPD) imaging of coronary arteries improves arterial wall visualization and quantitative assessment by increasing the success rate of obtaining good- to excellent-quality images and sections orthogonal to the longitudinal axis of the vessel. The technique also resulted in vessel wall thickness measurements that show a more distinct difference between healthy subjects and those with CAD risk factors, new research shows.
In the study of 12 healthy subjects and 26 with at least one CAD risk factor, Khaled Z. Abd-Elmoniem, Ph.D., of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, and colleagues developed the TRAPD coronary vessel wall imaging sequence and validated it with a flow phantom. Researchers obtained time-resolved coronary artery wall images at three to five cine cases in all subjects and made qualitative and quantitative comparisons between TRAPD and conventional single-image wall measurements.
Use of three to five frames increased the success rate of acquiring at least one image of good to excellent quality from 76 percent in single-image acquisitions to 95 percent with the TRAPD sequence, results showed. The difference in vessel wall thickness between healthy subjects and CAD risk factor subjects was significant with the TRAPD sequence, according to the authors.
“Preliminary experience with the TRAPD sequence in healthy subjects and subjects with risk factors for coronary artery disease suggests improved ability to distinguish coronary wall thickness between the two groups compared with that with single-frame dual inversion-recovery imaging,” the authors write.