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Purpose: To evaluate if the Breast Imaging Reporting and Data System (BI-RADS) ultrasound descriptor of orientation can be used in magnetic resonance imaging (MRI)., Materials and Methods: We conducted a retrospective study to evaluate breast mass lesions identified by MRI from 2008 to 2010 who had ultrasound (US) and histopathologic confirmation. Lesions were measured in the craniocaudal (CC), anteroposterior (AP), and transverse (T) axes and classified as having a nonparallel orientation, longest axis perpendicular to Cooper's ligaments, or in a parallel orientation when the longest axis is parallel to Cooper's ligaments. The MR image data were correlated with the US orientation according to BI-RADS and histopathological diagnosis., Results: We evaluated 71 lesions in 64 patients. On MRI, 27 lesions (38.0%) were nonparallel (8 benign and 19 malignant), and 44 lesions (62.0%) were parallel (33 benign and 11 malignant). There was significant agreement between the lesion orientation on US and MRI (kappa value = 0.901). The positive predictive values (PPV) for parallel orientation malignancy on MR and US imaging were 70.4% and 73.1%, respectively., Conclusion: A descriptor of orientation for breast lesions can be used on MRI with PPV for malignant lesions similar to US., (Copyright © 2012 Wiley Periodicals, Inc.)

In this review we describe the problem of overutilization of high-cost imaging modalities, especially magnetic resonance imaging (MRI) and computed tomography (CT). The overuse of CT is numerically more dramatic and also carries with it the not insignificant risk of harm to patients, namely, induction of radiation-induced malignancies. We report what is known of these risks in various imaging scenarios. The use of Radiology Business Managers is described as a means adopted to control overuse and the limitations of this strategy. The imperative of appropriate utilization is focused on, with emphasis placed on computer-based medical decision support. Impediments to appropriate use, however, exist, with concerns of medicolegal liability high on the list of these issues. Finally, we recommend that radiologists take the lead in the reform process by implementing strategies such as decision support., (Copyright © 2011 Wiley Periodicals, Inc.)

Purpose: To evaluate the diagnostic image quality of postgadolinium water excitation-magnetization-prepared rapid gradient-echo (WE-MPRAGE) sequence in abdominal examinations of noncooperative patients at 1.5 Tesla (T) and 3.0T MRI., Materials and Methods: Eighty-nine consecutive patients (48 males and 41 females; mean age +/- standard deviation, 54.6 +/- 16.6 years) who had MRI examinations including postgadolinium WE-MPRAGE were included in the study. Of 89 patients, 33 underwent noncooperative protocol at 1.5T, 10 underwent noncooperative protocol at 3.0T, and 46 underwent cooperative protocol at 3.0T. Postgadolinium WE-MPRAGE, MPRAGE, and three-dimensional gradient-echo sequences of these three different groups were qualitatively evaluated for image quality, extent of artifacts, lesion conspicuity, and homogeneity of fat-attenuation by two reviewers retrospectively, independently, and blindly. The results were compared using Wilcoxon signed rank and Mann-Whitney U tests. Kappa statistics were used to measure the extent of agreement between the reviewers., Results: The average scores indicated that the images were diagnostic for WE-MPRAGE at 1.5T and 3.0T in noncooperative patients. WE-MPRAGE achieved homogenous fat-attenuation in 31/33 (94%) of noncooperative patients at 1.5T and 10/10 (100%) of noncooperative patients at 3.0T. WE-MPRAGE at 3.0T had better results for image quality, extent of artifacts, lesion conspicuity and homogeneity of fat-attenuation compared with WE-MPRAGE at 1.5T, in noncooperative patients (P = 0.0008, 0.0006, 0.0024, and 0.0042; respectively). Kappa statistics varied between 0.76 and 1.00, representing good to excellent agreement., Conclusion: WE-MPRAGE may be used as a T1-weighted postgadolinium fat-attenuated sequence in noncooperative patients, particularly at 3.0T MRI., ((c) 2008 Wiley-Liss, Inc.)

Purpose: To assess the frequency of occurrence of poorly-marginated and focally-defined pancreatic ductal adenocarcinoma by MRI and to determine whether these appearances correlate with clinical features and histopathological grade., Materials and Methods: Institutional review board with waiver of informed consent was obtained for this HIPAA compliant study. A total of 33 patients (16 female, 17 male, mean age = 63.5 +/- 12.8, ranging from 41 to 80 years) with histopathologically-proven pancreatic ductal adenocarcinoma who underwent MR examination between August 2000 and February 2005 were retrospectively evaluated. Clinical data and histopathological tumoral grade were obtained from clinical charts; nine of 33 patients were excluded of the histopathological evaluation since their diagnosis was performed by fine needle aspiration biopsy and it was not possible to obtain the histopathological grade. Two radiologists reviewed all cases independently to identify whether cancers were poorly-marginated or focally-defined. Agreement between radiologists was assessed using the kappa coefficient. The overall correlation between imaging findings, clinical features, and histopathological grade was assessed with contingency tables using the Fisher's exact test., Results: Of the 33 patients, nine (27.2%) were classified as poorly-marginated and 24 (72.8%) as focally-defined. Agreement between the two reviewers was excellent (k = 0.92, 95% confidence interval (CI) = 0.78-1.0). Poorly-marginated cancers exhibited well- to moderately-differentiated histopathology in 71.4% of cases, while focally-defined cancers had well- to moderately-differentiated histopathology in 17.6% of cases, P = 0.02., Conclusion: A poorly-marginated appearance of pancreatic ductal carcinoma on MRI is not uncommon. These cancers exhibited statistically significant moderate- to well-differentiated histopathology compared to focally-defined cancers., ((c) 2007 Wiley-Liss, Inc.)

Purpose: To determine the accuracy of MRI including T1-weighted gadolinium (Gd)-enhanced three-dimensional-gradient-echo (3D-GE) sequences to distinguish pancreatic cancer from chronic pancreatitis in patients with pancreatic mass or focal enlargement., Materials and Methods: The study included 22 patients (15 males and seven females; mean age +/- SD, 56.2 +/- 11.5 years) with pancreatic mass or focal enlargement. Fourteen had pancreatic carcinoma and eight had chronic pancreatitis based on the histopathological and clinical findings. MRI examinations of all patients were retrospectively evaluated by two independent reviewers for the predetermined imaging findings of carcinoma and chronic pancreatitis. The accuracy of MRI for differentiating pancreatic carcinoma from chronic pancreatitis was determined. MRI findings of both entities were compared using t-tests, chi-squared tests, and logistic regression analyses for the differentiation of these two entities. The extent of agreement between two reviewers was determined with Kappa statistics., Results: The sensitivity and specificity of MRI including T1-weighted 3D-GE sequences for differentiating pancreatic carcinoma from chronic pancreatitis were 93% (13/14) and 75% (6/8), respectively. The most discriminative finding for pancreatic carcinoma was relative demarcation of the mass compared to background pancreas in contrast to chronic pancreatitis on post-Gd 3D-GRE sequences (P < 0.05)., Conclusion: MRI including Gd-enhanced T1-weighted 3D-GE sequences can differentiate pancreatic carcinoma from chronic pancreatitis successfully in most cases., ((c) 2007 Wiley-Liss, Inc.)

"When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others." Bertrand Russell (1872-1970) Computed tomography (CT) is one of the largest contributors to man-made radiation doses in medical populations. CT currently accounts for over 60 million examinations in the United States, and its use continues to grow rapidly. The principal concern regarding radiation exposure is that the subject may develop malignancies. For this systematic review we searched journal publications in MEDLINE (1966-2006) using the terms "CT," "ionizing radiation," "cancer risks," "MRI," and "patient safety." We also searched major reports issued from governmental U.S. and world health-related agencies. Many studies have shown that organ doses associated with routine diagnostic CT scans are similar to the low-dose range of radiation received by atomic-bomb survivors. The FDA estimates that a CT examination with an effective dose of 10 mSv may be associated with an increased chance of developing fatal cancer for approximately one patient in 2000, whereas the BEIR VII lifetime risk model predicts that with the same low-dose radiation, approximately one individual in 1000 will develop cancer. There are uncertainties in the current radiation risk estimates, especially at the lower dose levels encountered in CT. To address what should be done to ensure patient safety, in this review we discuss the "as low as reasonably achievable" (ALARA) principle, and the use of MRI as an alternative to CT., ((c) 2007 Wiley-Liss, Inc.)