The following are highlights from the current issues of RSNA’s peer-reviewed journals.
Oncologically Relevant Findings Reporting and Data System (ONCO-RADS): Guidelines for the Acquisition, Interpretation, and Reporting of Whole-Body MRI for Cancer Screening
Acknowledging the increasing number of studies describing the use of whole-body MRI for cancer screening and the increasing number of examinations performed in patients with known cancers, an international multidisciplinary expert panel of radiologists and a geneticist with subject-specific expertise formulated technical acquisition standards, interpretation criteria and limitations of whole-body MRI for cancer screening in individuals at higher risk, including those with cancer predisposition syndromes.
In an article published in Radiology, Giuseppe Petralia, MD, IEO European Institute of Oncology IRCCS, Milan, Italy, and colleagues reviewed the Oncologically Relevant Findings Reporting and Data System (ONCO-RADS) recommendations that are designed to promote standardization and diminish variations in the acquisition, interpretation and reporting of whole-body MRI scans obtained for cancer screening in individuals with cancer predisposition syndromes.
The specific aims of the ONCORADS recommendations are to establish minimum acceptable technical parameters for whole-body MRI data acquisition for cancer screening in high-risk patients and asymptomatic individuals in the general population; develop standardized data collection methods that enable detailed descriptions of the abnormal findings across multiple anatomic regions; assign the likelihood of malignancy of abnormal findings by using a five-category assessment score to direct further management; enable data collection for outcome evaluations in the context of clinical trials; provide training and educational materials for radiologists on whole-body MRI reporting for cancer screening to limit the variability of imaging interpretations; enhance communication with and between radiologists and with referring clinicians; and promote quality assurance and research in whole-body MRI for cancer screening.
“ONCO-RADS recommendations fulfill the need to promote standardization and diminish variations in the acquisition, interpretation, and reporting of whole-body MRI for cancer screening. The system is designed for guiding clinical care but has the potential for incorporation into clinical trials,” the authors write.
Read the full article at RSNA.org/Radiology.
Ischemic Heart Disease: Noninvasive Imaging Techniques and Findings
A leading cause of death worldwide, ischemic heart disease comprises a large proportion of annual health care expenditure.
Management of ischemic heart disease is now best guided by the physiologic significance of coronary artery stenosis. While invasive coronary angiography is the standard for diagnosing coronary artery stenosis, it is expensive and has risks including vascular access site complications and contrast material– induced nephropathy.
Multiple imaging techniques can help in the detection of the physiologic significance of coronary artery stenoses: cardiac MR vasodilator or dobutamine stress imaging, CT stress perfusion imaging, CT, PET myocardial perfusion imaging (MPI), SPECT MPI and stress echocardiography.
In an article published in RadioGraphics, Arlene Sirajuddin, MD, Cardiovascular and Pulmonary Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, and colleagues summarized current indications and contraindications for noninvasive imaging techniques for detection of ischemic heart disease secondary to epicardial, illustrated the spectrum of imaging findings of ischemic heart disease and highlighted the advantages and disadvantages of the various noninvasive imaging methods used to assess ischemic heart disease, as illustrated by recent clinical trials.
Overall, the available evidence supports that the best noninvasive study to functionally assess coronary stenosis currently is cardiac MR stress perfusion imaging (sensitivity 90%, specificity 94%), closely followed by PET MRI (sensitivity 87%, specificity 84%).
“Advances in multiple noninvasive imaging techniques, in particular quantitative capabilities in MRI, CT, and PET, allow accurate detection and functional assessment of CAD in patients with intermediate to high pretest probability and have enabled these noninvasive imaging methods to assume a key role in guiding therapeutic intervention,” the authors conclude.
Read the full article at RSNA.org/RadioGraphics.
T2-weighted Lung Imaging Using a 0.55-T MRI System
Clinical evaluation of lung structure and disease primarily relies on CT and radiographic imaging. CT can provide thin-section volumetric imaging at fast acquisition speeds. MRI may offer additional soft-tissue characterization with adaptable image weighting (e.g., T1, T2).
In the lung, however, structural proton MRI suffers from low proton density and susceptibility gradient artifacts, thereby hampering the attainable image quality. And when compared with CT, MRI provides lower spatial resolution and requires long examination times. Despite substantial technical advances, the clinical role of structural MRI in lung imaging remains limited. Recent developments in ultrashort echo time gradient-echo imaging at 1.5 and 3 T have generated promising T1-weighted images.
In a study in Radiology: Cardiothoracic Imaging, Adrienne E. Campbell-Washburn, PhD, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, and colleagues compared respiratory-triggered T2-weighted turbo spin-echo MRI at 0.55 T with clinical CT scans in 24 participants with common lung abnormalities. Diffuse disease, including ground-glass opacities and tree-in-bud nodules, were the findings most difficult to discern using MRI, with false readings in four of 18 patients for each feature. Nodule size, which was measured independently at CT and MRI, was strongly correlated for nodules with a measurement of 10 mm ± 5 (range, 5–23 mm).
“Our findings in this small sample of patients indicate excellent image quality that shows promise for clinical diagnosis and evaluation of common lung disease,” the authors write.
To read the full article, go to RSNA.org/Cardiothoracic.