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Objectives: To assess the ability of multislice detector computed tomography (MDCT) to differentiate old versus acute/subacute vertebral fractures (VF) and to identify characteristic MDCT imaging signs., Methods: 74 consecutive patients demonstrated 192 VF that were classified as either acute/subacute or old based on magnetic resonance imaging, MDCT, and clinical information as reference standard. Classification as acute/subacute versus old fractures based on MDCT alone was evaluated on a Likert scale by 2 independent radiologists. Morphologic MDCT features of fractures, such as trabecular compaction or fracture line, were recorded. Receiver operating characteristic analyses and Cohen's κ were used to assess the discriminatory power of the MDCT and interrater agreement, respectively., Results: Out of all 192 VF, 148 fractures were acute/subacute and 44 were old according to the reference standard. Receiver operating characteristic analyses of sole MDCT assessment showed very good identification of acute/subacute VF, with areas under the curve of 0.854 and 0.861 for readers 1 and 2, respectively. When indeterminate findings were treated as acute/subacute fractures, sensitivity and specificity were 97.2% and 58.1% for reader 1 and 94.5% and 65.1% for reader 2. Interrater agreement regarding fracture age was good (weighted Cohen's κ = 0.607). Trabecular compression/callus distinct from the cortex (double compaction sign) was present in approximately half of acute/subacute VF and highly specific for acute/subacute VF (specificity = 93.2% and 88.6% for readers 1 and 2, respectively)., Conclusion: The acuity of VF can be assessed by MDCT alone with high sensitivity and in case of a double compaction sign with high specificity., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: To investigate the Liver Imaging Reporting and Data System (LI-RADS) v2014 categorization of hepatocellular carcinomas (HCCs) on gadoxetic acid-enhanced magnetic resonance imaging (Gd-EOB-MRI) in comparison with multiphasic multidetector computed tomography (MDCT)., Materials and Methods: Our Institutional Review Board approved this retrospective study and waived the requirement for informed consent. We included 182 high-risk patients with 216 pathologically confirmed HCCs who underwent both Gd-EOB-MRI at 1.5 or 3T and multiphasic MDCT. Two independent radiologists assessed the presence or absence of major HCC features and assigned LI-RADS categories before and after considering ancillary features on both MRI and MDCT. Finally, sensitivities of LR-5/5v and frequencies of major HCC features were compared between MRI and MDCT using the McNemar test., Results: Sensitivities of LR-5/5v were not significantly different between MRI and MDCT (63.4% [137/216] vs. 64.4% [139/216], P = 0.831; 60.6% [131/216] vs. 60.6% [131/216], P = 0.868, for reviewers 1 and 2, respectively). Among major HCC features seen on consensus review, washout and capsule appearance were less frequently observed on MRI than on MDCT (69.0% [149/216] vs. 87.0% [188/216], P < 0.001 and 17.1% [37/216] vs. 31.5% [68/216], P < 0.001), while no significant differences were found for arterial hyperenhancement (88.9% [192/216] vs. 84.7% [183/216], P = 0.081). Ancillary features led to category changes in 18.1% (39/216) of nodules on MRI (all, LR-3 to LR-4), while no changes were seen on MDCT., Conclusion: Using LI-RADS, Gd-EOB-MRI showed comparable sensitivity to multiphasic MDCT for the diagnosis of HCCs, and ancillary features of MRI frequently led to the upgrade of nodules from LR-3 to LR-4., Level of Evidence: 3 J. Magn. Reson. Imaging 2017;45:731-740., (© 2016 International Society for Magnetic Resonance in Medicine.)

The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every two years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. The Atlanta Classification by the Acute Pancreatitis Classification Working Group recently modified the terminology for the clinical course and the morphologic changes identified on imaging, primarily contrast- enhanced multidetector computed tomography (MDCT). The two distinct clinical courses of the disease are classified as (1) early phase, which lasts approximately 1 week, and (2) late phase, which starts after the first week and can last for months after the initial episode. The two, primary, morphologic changes are acute, interstitial edematous and necrotizing pancreatitis. Timing of imaging, primarily MDCT, is based on the clinical phases and is, therefore, important for these imaging guidelines. Ultrasound's role is to detect gallstones after the first episode. MDCT plays a primary role in the management of acutely ill patients, only after a minimum of 48-72 hours and generally after one week. MR plays a supplementary role to MDCT. Follow-up MDCT guides management and therapy: percutaneous aspiration of fluid collections and/or placement of large caliber catheters in infected necrosis.

Computed tomography coronary angiography (CTA) and cardiac magnetic resonance myocardial perfusion imaging (CMR-MPI) are state-of-the-art tools for noninvasive assessment of coronary artery disease (CAD). We aimed to compare the diagnostic accuracy of CTA and CMR-MPI for the detection of functionally relevant CAD, using invasive coronary angiography (XA) with fractional flow reserve (FFR) as a reference standard, and to evaluate the best protocol integrating these techniques for assessment of patients with suspected CAD. 95 patients (68 % men; 62 ± 8.1 years) with intermediate pre-test probability (PTP) of CAD underwent a sequential protocol of CTA, CMR-MPI and XA. Significant CAD was defined as >90 % coronary stenosis, 40-90 % stenosis with FFR ≤ 0.80 or left main stenosis ≥50 %. Prevalence of significant CAD was 43 %. CTA was more sensitive (100 %) but less specific (59 %) than CMR-MPI (88 and 89 %, respectively) for detection of significant CAD, with a strong trend for higher global diagnostic accuracy of CMR-MPI (88 vs. 77 %, p = 0.05). An integrated approach based on an initial CTA and subsequent referral to CMR-MPI of positive/inconclusive results had the best diagnostic performance (AUC 0.91). The direct referral to XA of patients with positive/inconclusive CTA performed worse than a selective approach based on CMR-MPI results (AUC 0.80 vs. 0.91, p = 0.005). In this intermediate PTP population, CMR-MPI showed a strong trend toward better performance compared to CTA for the assessment of functionally significant CAD. A combined protocol integrating coronary anatomy and function seems to be a very effective approach in the accurate diagnosis of CAD.

Object: Clearance of the cervical spine in patients who have sustained trauma remains a contentious issue. Clinical examination alone is sufficient in neurologically intact patients without neck pain. Patients with neck pain or those with altered mental status or a depressed level of consciousness require further radiographic evaluation. However, no consensus exists as to the appropriate imaging modality. Some advocate multidetector CT (MDCT) scanning alone, but this has been criticized because MDCT is not sensitive in detecting ligamentous injuries that can often only be identified on MRI., Methods: Patients were identified retrospectively from a prospectively maintained database at a Level I trauma center. All patients admitted between January 2004 and June 2011 who had a cervical MDCT scan interpreted by a board-certified radiologist as being without evidence of acute traumatic injury and who also had a cervical MRI study obtained during the same hospital admission were included. Data collected included patient demographics, mechanism of injury, Glasgow Coma Scale score at the time of MRI, the indication for and findings on MRI, and the number, type, and indication for cervical spine procedures., Results: A total of 1004 patients were reviewed, of whom 614 were male, with an overall mean age of 47 years. The indication for MRI was neck pain in 662 patients, altered mental status in 467, and neurological signs or symptoms in 157. The MRI studies were interpreted as normal in 645 patients, evidencing ligamentous injury alone in 125, and showing nonspecific degenerative changes in the remaining patients. Of the 125 patients with ligamentous injuries, 66 (52.8%) had documentation of clearance (29 clinical, 37 with flexion-extension radiographs). Another 32 patients were presumed to be self-cleared, bringing the follow-up rate to 82% (98 of 119). Five patients died prior to clearance, and 1 patient was transferred to another facility prior to clearance. Based on these data, the 95% confidence interval for the assertion that clinically irrelevant ligamentous injury in the face of normal MDCT is 97%-100%. No patient with ligamentous injury on MRI was documented to require a surgical procedure or halo orthosis for instability. Thirty-nine patients ultimately underwent cervical surgical procedures (29 anterior and 10 posterior; 5 delayed) for central cord syndrome (21), quadriparesis (9), or discogenic radicular pain (9). None had an unstable spine., Conclusions: In this study population, MRI did not add any additional information beyond MDCT in identifying unstable cervical spine injuries. Magnetic resonance imaging frequently detected ligamentous injuries, none of which were found to be unstable at the time of detection, during the course of admission, or on follow-up. Magnetic resonance imaging provided beneficial clinical information and guided surgical procedures in patients with neurological deficits or radicular pain. An MDCT study with sagittal and coronal reconstructions negative for acute injury in patients without an abnormal motor examination may be sufficient alone for clearance.

Purpose: To evaluate morphologic characteristics and establish a standardized diagnostic algorithm to differentiate benign cystic pancreatic tumors (CPTs) in non-pancreatitis patients using multidetector computed tomography (CT) and magnetic resonance imaging (MRI)., Materials and Methods: Patients with histopathologically proven CPTs who had undergone MRI and/or CT and subsequent tumor resection in our institution were retrospectively identified. Images were analyzed for morphology and enhancement patterns by three independent blinded observers. Preoperative image findings were correlated with histopathological results. Based on the evaluated morphologic parameters, a standardized diagnostic algorithm was designed to help characterize the lesions., Results: A total of 62 consecutive patients with 64 CPTs were identified from the surgical database (21 intraductal papillary mucinous neoplasms; 10 mucinous cystic neoplasms; 12 serous microcystic adenomas; 3 serous oligocystic adenomas; 6 solid pseudopapillary tumors; 12 neuroendocrine neoplasms). The overall averaged accuracy for the 3 observers was 89.9 % for CT and 93.1 % for MRI with increasing overall accuracy in relation to the experience of the observer (88.2 %, 91.5 %, and 93.8 %, respectively). Overall, the generalized kappa value was 0.69 (CT, 0.64; MRI, 0.76); p < 0.001). The accuracy of the standardized diagnostic algorithm was 91.1 %., Conclusion: It is possible to characterize benign CPTs with MRI and CT, while MRI appears to be superior to CT. Diagnostic accuracy depends on the observer's experience. The standardized algorithm can aid in the differential diagnosis but still needs to be tested in other patient populations., (© Georg Thieme Verlag KG Stuttgart · New York.)