Correction to: Effects of Physician Experience, Specialty Training, and Self-referral on Inappropriate Diagnostic Imaging.

There were some errors in the variables in this paper.

Effects of Physician Experience, Specialty Training, and Self-referral on Inappropriate Diagnostic Imaging.

BACKGROUND: Although previous research has demonstrated high rates of inappropriate diagnostic imaging, the potential influence of several physician-level characteristics is not well established. OBJECTIVE: To examine the influence of three types of physician characteristics on inappropriate imaging: experience, specialty training, and self-referral. DESIGN: A retrospective analysis of over 70,000 MRI claims submitted for commercially insured individuals. Physician characteristics were identified through a combination of administrative records and primary data collection. Multi-level modeling was used to assess relationships between physician characteristics and inappropriate MRIs. SETTING: Massachusetts PARTICIPANTS: Commercially insured individuals who received an MRI between 2010 and 2013 for one of three conditions: low back pain, knee pain, and shoulder pain. MEASUREMENTS: Guidelines from the American College of Radiology were used to classify MRI referrals as appropriate/inappropriate. Experience was measured from the date of medical school graduation. Specialty training comprised three principal groups: general internal medicine, family medicine, and orthopedics. Two forms of self-referral were examined: (a) the same physician who ordered the procedure also performed it, and (b) the physicians who ordered and performed the procedure were members of the same group practice and the procedure was performed outside the hospital setting. RESULTS: Approximately 23% of claims were classified as inappropriate. Physicians with 10 or less years of experience had significantly higher odds of ordering inappropriate MRIs. Primary care physicians were almost twice as likely to order an inappropriate MRI as orthopedists. Self-referral was not associated with higher rates of inappropriate MRIs. LIMITATIONS: Classification of MRIs was conducted with claims data. Not all self-referred MRIs could be detected. CONCLUSIONS: Inappropriate imaging continues to be a driver of wasteful health care spending. Both physician experience and specialty training were highly associated with inappropriate imaging.

Pancreatic perfusion modulation following glucose stimulation assessed by noninvasive arterial spin labeling (ASL) MRI.

BACKGROUND: More than 100 million adults in the US suffer from prediabetes or type-2 diabetes. Noninvasive imaging of pancreas endocrine function might provide a surrogate marker of ß-cell functional integrity loss linked to this disease. PURPOSE: To noninvasively assess pancreatic blood-flow modulation following a glucose challenge using arterial spin labeling (ASL) MRI. STUDY TYPE: Prospective. SUBJECTS: Fourteen adults (30 ± 7 years old, 3M/11F, body mass index [BMI] = 24 ± 3 kg.m-2 ). FIELD STRENGTH/SEQUENCE: 3T MRI / background-suppressed pseudocontinuous PCASL preparation with single-shot fast-spin-echo (FSE) readout before and after an oral glucose challenge using either fruit juice (n = 7) or over-the-counter glucose gel (n = 7). ASSESSMENT: Subjects were fasting prior to initiation of oral stimulation, then dynamic perfusion measurements were performed every 2 minutes for 30 minutes. We quantified absolute blood flow at each timepoint. STATISTICAL TESTS: Repeated-measures analysis of variance (ANOVA) followed by paired t-tests to assess for a significant effect of glucose challenge on measured perfusion. RESULTS: Measured basal blood flow was 187 ± 53 mL/100g/min. A significant blood flow increase of +38 ± 26% was observed 10 minutes poststimulation (P < 0.05) and continuing until the end of the experiment. The gel stimulation provided the most consistent results, with an early rise followed by an additional later increase consistent with the known pancreatic insulin response to elevated blood glucose. Across-subject variations in blood flow increase were partially attributable to basal flow, with a negative correlation of r = -0.84 between basal and maximal relative flow increase in the gel group. DATA CONCLUSION: ASL can be used to measure pancreatic flow in response to a glucose challenge, which could be linked to insulin release and secretion. This paradigm might be useful to characterize disorders of glucose regulation. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2020;51:854-860.

Pancreatic Ductal Adenocarcinoma and Its Variants: Pearls and Perils.

Pancreatic ductal adenocarcinoma (PDAC), an epithelial neoplasm derived from the pancreatic ductal tree, is the most common histologic type of pancreatic cancer and accounts for 85%-95% of all solid pancreatic tumors. As a highly lethal malignancy, it is the seventh leading cause of cancer death worldwide and is responsible for more than 300 000 deaths per year. PDAC is highly resistant to current therapies, affording patients a 5-year overall survival rate of only 7.2%. It is characterized histologically by its highly desmoplastic stroma embedding tubular and ductlike structures. On images, it typically manifests as a poorly defined hypoenhancing mass, causing ductal obstruction and vascular involvement. Little is known about the other histologic subtypes of PDAC, mainly because of their rarity and lack of specific patterns of disease manifestation. According to the World Health Organization, these variants include adenosquamous carcinoma, colloid carcinoma, hepatoid carcinoma, medullary carcinoma, signet ring cell carcinoma, undifferentiated carcinoma with osteoclast-like giant cells, and undifferentiated carcinoma. Depending on the subtype, they can confer a better or even worse prognosis than that of conventional PDAC. Thus, awareness of the existence and differentiation of these variants on the basis of imaging and histopathologic characteristics is crucial to guide clinical decision making for optimal treatment and patient management.

Feasibility, safety, and utility of brain MRI for patients with non-MRI-conditioned CIED.

Feasibility, safety, and utility of brain MRI for patients with non-MRI-conditioned cardiac implantable electrical devices (CIEDs) remains controversial. While a growing number of studies have shown safe employment in select patients under strict protocols, there is an increasing clinical need for further off-label investigations. To assess the feasibility and utility of brain MRI in neurological and neurosurgical patients with non-MRI-conditioned CIEDs using off-label protocol. We retrospectively evaluated 126 patients with non-MRI-conditioned CIEDs referred to our hospital between 2014 to 2018 for MRI under an IRB-approved protocol. A total of 126 off-label brain MRI scans were performed. The mean age was 67.5 ± 13.0. Seventy percent of scans were performed on female patients. Indications for MRI are neurosurgical (45.2%), neurological (51.6%), and others (3.2%). MRI utilization for tumor cases was highest for tumor cases (68.3%), but employment was valuable for vascular (12.7%), deep brain stimulators (3.2%), and other cases (15.9%). In the tumor category, (37.2%) of the scans were performed for initial diagnosis and pre-surgical planning, (47.7%) for post-intervention evaluation/surveillance, (15.1%) for stereotactic radiosurgery treatment (CyberKnife). No clinical complications were encountered. No functional device complications of the CIED were identified during and after the MRI in 96.9% of the studies. A 49.6% of the off-label brain MRI scans performed led to a clinically significant decision and/or intervention for the patients. A 42.9% of obtained MRI studies did not change the plan of care. A 7.9% of post-scan decision-making data was not available. We demonstrate that off-label brain MRI scans performed on select patients under a strict protocol is feasible, safe, and relevant. Almost 50% of scans provided critical information resulting in clinical intervention of the patients.

Accuracy of a novel noninvasive secretin-enhanced MRCP severity index scoring system for diagnosis of chronic pancreatitis: correlation with EUS-based Rosemont criteria.

PURPOSE: To evaluate the accuracy of a secretin-enhanced MRCP Chronic Pancreatitis Severity Index (CPSI) in the diagnosis of chronic pancreatitis (CP) based on endoscopic ultrasound (EUS) Rosemont criteria. METHODS: In this retrospective study, 31 patients (20 women; median age 48 years, range 18-77) with known/suspected CP evaluated with both EUS and secretin-enhanced MRCP were included. CP severity was graded using a ten-point-scale secretin-enhanced MRCP-based CPSI scoring system which considered ductal, parenchymal and secretin-based dynamic abnormalities. Cases were categorized as normal, mild, moderate or severe CP. Correlation between CPSI and the EUS Rosemont criteria was performed using Cohen's kappa coefficient. Comparative evaluation of test performance was obtained using ROC analysis. RESULTS: Using EUS Rosemont criteria, eight patients had features consistent/suggestive of CP, 20 patients were normal and three were indeterminate. On CPSI, five patients were normal, 12 had mild and 14 had moderate/severe CP. There was only fair agreement (k = 0.272) between CPSI and Rosemont criteria categories. CPSI showed 87.5% sensitivity, 69.6% specificity and 74.2% accuracy (cutoff value = 3.5 points; area under the curve = 0.804; p = 0.0026) for CP diagnosis based on EUS Rosemont criteria. CONCLUSION: CPSI showed relatively high diagnostic accuracy for diagnosis of CP based on Rosemont criteria. The CPSI scoring system can be proposed as a noninvasive alternative to the EUS Rosemont criteria for CP diagnosis.

Pancreatic perfusion and arterial-transit-time quantification using pseudocontinuous arterial spin labeling at 3T.

PURPOSE: To demonstrate the feasibility of noninvasively measuring pancreatic perfusion using pseudocontinuous arterial spin labeling (ASL) and to derive quantitative blood-flow and transit-time measurements in healthy volunteers. METHODS: A pseudocontinuous ASL sequence with background suppression and a single-slice single-shot fast-spin-echo readout was acquired at 3 T in 10 subjects with a single standard postlabeling delay (PLD) of 1.5 s and in 4 additional subjects with 4 PLD from 0.7 to 2 s. An imaging synchronized breathing approach was used to minimize motion artifacts during the 3 min of acquisition. Scan-rescan reproducibility was assessed in 3 volunteers with single-delay ASL. Quantitative blood flow and arterial transit time (ATT) were derived and the impact of ATT correction was studied using either subject-specific ATT in the second group or an average ATT derived from the group with multidelay ASL for subjects with single-delay ASL. RESULTS: Successful ASL acquisitions were performed in all volunteers. An average pancreatic blood flow of 201 ± 40 mL/100 g/min was measured in the single-delay group using an assumed ATT of 750 ms Average ATT measured in the multidelay group was 1029 ± 89 ms Using the longer, measured ATT reduced the measured flow to 162 ± 12 and 168 ± 28 mL/100 g/min with subject-specific or average ATT correction, respectively. ASL signal heterogeneities were observed at shorter PLD, potentially linked to its complex vascular supply and islet distribution. CONCLUSIONS: ASL enables reliable measurement of pancreatic perfusion in healthy volunteers. It presents a valuable alternative to contrast-enhanced methods and may be useful for diagnosis and characterization of several inflammatory, metabolic, and neoplastic diseases affecting the pancreas.

Incidental pulmonary embolism in pancreatic ductal adenocarcinoma: Impact of tumor and AJCC stages at initial staging CT.

BACKGROUND/OBJECTIVES: To determine the prevalence of incidental pulmonary embolism (PE) detected during initial staging CT among patients with newly diagnosed pancreatic ductal adenocarcinoma (PDAC) and assess their association with underlying tumor burden. MATERIALS AND METHODS: This retrospective cohort study evaluated staging chest CT scans (2013-2017) to identify PE among patients with treatment naïve, biopsy-proven PDAC. Data included age, sex, T stage, AJCC stage, presence/absence of metastases and their location at diagnosis. The association of PE with tumor (T1-T4) and AJCC stage were assessed using Pearson Chi-square and Fischer's exact test. A threshold p-value of <0.05 indicated statistical significance. RESULTS: A total of 174 patients (90 female, mean age, 68 years; range: 34-93) were identified, of which 10 patients harbored incidental PE (prevalence, 5.7%). In the PE group, two patients presented with distant metastasis (liver, 20%), while eight patients had T4 tumors (80%). No statistical association was detected between PE and age, sex, and the presence/absence or location of distant metastasis (p = 0.065, p = 0.59, p = 0.687 and p = 0.933, respectively). Patients with T4 tumors and higher AJCC stages (stage III/IV) were significantly more likely to present with PE than those with lower T stage (p = 0.045) and AJCC stage (stage I/II; p = 0.017). CONCLUSION: The prevalence of incidental PE among PDAC patients undergoing initial CT staging is 5.7%. Patients with T4 and AJCC stages III/IV are at higher risk of PE. Caution should be exercised during radiographic interpretation of initial staging chest CTs, as incidental PE may be lurking and require treatment.

DWI of Pancreatic Ductal Adenocarcinoma: A Pilot Study to Estimate the Correlation With Metastatic Disease Potential and Overall Survival.

OBJECTIVE: The purpose of this study is to analyze the relationship between the apparent diffusion coefficient (ADC) of pancreatic ductal adenocarcinoma (PDAC) and the presence or development of metastasis and overall survival (OS). MATERIALS AND METHODS: Of 290 consecutive patients with histopathologically proven PDAC from January 2013 to December 2014, staging DWI was performed for 124 patients. Image quality was adequate in 112 studies. Sixty-five patients were treatment naïve, but 17 of the 65 were excluded because of the presence of other associated pancreatic pathologic abnormalities. Data for the remaining 48 patients (24 men and 24 women; median age, 65.5 years; interquartile range, 56-77 years) were obtained during a 4-year follow-up period (mean [± SD], 397 ± 415.1 days). The correlation between ADC and the presence or development of metastasis was assessed using descriptive statistics. OS was determined and mortality analysis was performed using Pearson correlation and Kaplan-Meier curves. RESULTS: Of 48 patients, 10 had metastases at staging MRI, and 12 later developed metastatic disease. Among the latter, the mean time from staging MRI to metastasis was 258 ± 274.1 days. Most (86%) metastases were hepatic (n = 19). During the follow-up period, the remaining 26 patients (54%) never developed metastases. Patients with metastatic disease (n = 22) had significantly lower mean ADCs than did those without metastases (1.27 × 10-3 vs 1.43 × 10-3 mm2/s; p = 0.047). The ADC of PDAC had a positive correlation with survival: patients with PDAC with lower ADCs (< 1.36 × 10-3 mm2/s) had significantly worse 4-year OS rates than did patients with higher ADC values (p = 0.036). CONCLUSION: Pretreatment ADC values of PDAC may be significantly lower in patients who have or will develop metastatic disease and may correlate with worse OS.

Structured vs narrative reporting of pelvic MRI for fibroids: clarity and impact on treatment planning.

OBJECTIVES: To evaluate clarity and usefulness of MRI reporting of uterine fibroids using a structured disease-specific template vs. narrative reporting for planning of fibroid treatment by gynaecologists and interventional radiologists. METHODS: This is a HIPAA-compliant, IRB-approved study with waiver of informed consent. A structured reporting template for fibroid MRIs was developed in collaboration between gynaecologists, interventional and diagnostic radiologists. The study population included 29 consecutive women who underwent myomectomy for fibroids and pelvic MRI prior to implementation of structured reporting, and 42 consecutive women with MRI after implementation of structured reporting. Subjective evaluation (on a scale of 1-10, 0 not helpful; 10 extremely helpful) and objective evaluation for the presence of 19 key features were performed. RESULTS: More key features were absent in the narrative reports 7.3 ± 2.5 (range 3-12) than in structured reports 1.2 ± 1.5 (range 1-7), (p < 0.0001). Compared to narrative reports, gynaecologists and radiologists deemed structured reports both more helpful for surgical planning (p < 0.0001) (gynaecologists: 8.5 ± 1.2 vs. 5.7 ± 2.2; radiologists: 9.6 ± 0.6 vs. 6.0 ± 2.9) and easier to understand (p < 0.0001) (gynaecologists: 8.9 ± 1.1 vs. 5.8 ± 1.9; radiologists: 9.4 ± 1.3 vs. 6.3 ± 1.8). CONCLUSION: Structured fibroid MRI reports miss fewer key features than narrative reports. Moreover, structured reports were described as more helpful for treatment planning and easier to understand. KEY POINTS: • Structured reports missed only 1.2 ± 1.5 out of 19 key features, as compared to narrative reports that missed 7.3 ± 2.5 key features for planning of fibroid treatment. • Structured reports were more helpful and easier to understand by clinicians. • Structured template can provide essential information for fibroids treatment planning.

Optimizing Inpatient Body MRI Utilization: A Granular Look at Trends, Quality, Yield, and Timing.

OBJECTIVE: We sought to analyze body MRI utilization trends, quality, yield, and timing among inpatients in a tertiary care academic medical center. MATERIALS AND METHODS: By use of billing data from fiscal years (FYs) 2006-2015, the volume of admissions was compared with the total number of inpatient body MRI examinations. MRI examinations per admissions and discharge were adjusted using the Centers for Medicare & Medicaid Services case mix index by FY. Linear regression was used to assess trends. In addition, each inpatient body MRI examination performed in FY 2015 was evaluated and graded on its quality and yield and was judged as to whether it could have been performed on an outpatient basis. RESULTS: There was an increase in the number of inpatient body MRI examinations, from 637 examinations in FY 2006 to 871 examinations in FY 2015 (p = 0.005). By adjusting for case mix, the upward trend for body MRI use persisted (p = 0.012). Regarding quality, 2.3% of all inpatient body MRI examinations were nondiagnostic, 40.4% were limited quality, and 57.3% were of diagnostic quality. Concerning yield, 20.8% of all examinations had no yield, 5.1% of examinations had no yield but incidental findings, and 74.1% of examinations had a positive yield. Finally, regarding timing, 30.2% of examinations could have been performed as outpatient examinations. CONCLUSION: At our institution, the number of inpatient body MRI examinations has increased significantly over the past 10 years. Many of the examinations, however, are poor quality, often give redundant information, and could be performed in the outpatient setting.

Nonepithelial Neoplasms of the Pancreas, Part 2: Malignant Tumors and Tumors of Uncertain Malignant Potential From the Radiologic Pathology Archives.

Almost all neoplasms of the pancreas are derived from pancreatic epithelial components, including the most common pancreatic mass, primary pancreatic ductal adenocarcinoma (PDAC). Nonepithelial neoplasms comprise only 1%-2% of all pancreatic neoplasms. Although some may arise directly from intrapancreatic elements, many originate from mesenchymal, hematopoietic, or neural elements in the retroperitoneal peripancreatic space and grow into the pancreas. Once these tumors reach a certain size, it can be challenging to identify their origin. Because these manifest at imaging as intrapancreatic masses, awareness of the existence and characteristic features of these nonepithelial neoplasms is crucial for the practicing radiologist in differentiating these tumors from primary epithelial pancreatic tumors, an important distinction given the vastly different management and prognosis. In part 1 of this article, the authors reviewed benign nonepithelial neoplasms of the pancreas. This article focuses on malignant nonepithelial neoplasms and those of uncertain malignant potential that can be seen in the pancreas. The most common malignant or potentially malignant nonepithelial pancreatic tumors are of mesenchymal origin and include soft-tissue sarcomas, solitary fibrous tumor, and inflammatory myofibroblastic tumor. These tumors commonly manifest as large heterogeneous masses, often containing areas of necrosis and hemorrhage. The clinical features associated with these tumors and the imaging characteristics including enhancement patterns and the presence of fat or calcification help distinguish these tumors from PDAC. Hematopoietic tumors, including lymphoma and extramedullary plasmacytoma, can manifest as isolated pancreatic involvement or secondarily involve the pancreas as widespread disease. Hyperenhancing paragangliomas or hypervascular metastatic disease can mimic primary pancreatic neuroendocrine tumors or vascular anomalies.

Optimizing MRI Logistics: Prospective Analysis of Performance, Efficiency, and Patient Throughput.

OBJECTIVE: The objective of this study is to optimize MRI logistics through evaluation of MRI workflow and analysis of performance, efficiency, and patient throughput in a tertiary care academic center. SUBJECTS AND METHODS: For 2 weeks, workflow data from two outpatient MRI scanners were prospectively collected and stratified by value added to the process (i.e., value-added time, business value-added time, or non-value-added time). Two separate time cycles were measured: the actual MRI process cycle as well as the complete length of patient stay in the department. In addition, the impact and frequency of delays across all observations were measured. RESULTS: A total of 305 MRI examinations were evaluated, including body (34.1%), neurologic (28.9%), musculoskeletal (21.0%), and breast examinations (16.1%). The MRI process cycle lasted a mean of 50.97 ± 24.4 (SD) minutes per examination; the mean non-value-added time was 13.21 ± 18.77 minutes (25.87% of the total process cycle time). The mean length-of-stay cycle was 83.51 ± 33.63 minutes; the mean non-value-added time was 24.33 ± 24.84 minutes (29.14% of the total patient stay). The delay with the highest frequency (5.57%) was IV or port placement, which had a mean delay of 22.82 minutes. The delay with the greatest impact on time was MRI arthrography for which joint injection of contrast medium was necessary but was not accounted for in the schedule (mean delay, 42.2 minutes; frequency, 1.64%). Of 305 patients, 34 (11.15%) did not arrive at or before their scheduled time. CONCLUSION: Non-value-added time represents approximately one-third of the total MRI process cycle and patient length of stay. Identifying specific delays may expedite the application of targeted improvement strategies, potentially increasing revenue, efficiency, and overall patient satisfaction.

Optimizing MRI Logistics: Focused Process Improvements Can Increase Throughput in an Academic Radiology Department.

OBJECTIVE: The purpose of this study was to describe and evaluate the effect of focused process improvements on protocol selection and scheduling in the MRI division of a busy academic medical center, as measured by examination and room times, magnet fill rate, and potential revenue increases and cost savings to the department. MATERIALS AND METHODS: Focused process improvements, led by a multidisciplinary team at a large academic medical center, were directed at streamlining MRI protocols and optimizing matching protocol ordering to scheduling while maintaining or improving image quality. Data were collected before (June 2013) and after (March 2015) implementation of focused process improvements and divided by subspecialty on type of examination, allotted examination time, actual examination time, and MRI parameters. Direct and indirect costs were compiled and analyzed in consultation with the business department. Data were compared with evaluated effects on selected outcome and efficiency measures, as well as revenue and cost considerations. Statistical analysis was performed using a t test. RESULTS: During the month of June 2013, 2145 MRI examinations were performed at our center; 2702 were performed in March 2015. Neuroradiology examinations were the most common (59% in June 2013, 56% in March 2015), followed by body examinations (25% and 27%). All protocols and parameters were analyzed and streamlined for each examination, with slice thickness, TR, and echo train length among the most adjusted parameters. Mean time per examination decreased from 43.4 minutes to 36.7 minutes, and mean room time per patient decreased from 46.3 to 43.6 minutes (p = 0.009). Potential revenue from increased throughput may yield up to $3 million yearly (at $800 net revenue per scan) or produce cost savings if the facility can reduce staffed scanner hours or the number of scanners in its fleet. Actual revenue and expense impacts depend on the facility's fixed and variable cost structure, payer contracts, MRI fleet composition, and unmet MRI demand. CONCLUSION: Focused process improvements in selecting MRI protocols and scheduling examinations significantly increased throughput in the MRI division, thereby increasing capacity and revenue. Shorter scan and department times may also improve patient experience.

Pathologic Subtypes of Ampullary Adenocarcinoma: Value of Ampullary MDCT for Noninvasive Preoperative Differentiation.

OBJECTIVE: The purpose of this study was to evaluate the utility of ampullary MDCT in the noninvasive, preoperative differentiation of pancreatobiliary and intestinal subtypes of ampullary adenocarcinoma. MATERIALS AND METHODS: This retrospective study included 32 patients (20 men, 12 women; age range, 41-81 years) with resected ampullary adenocarcinoma who underwent preoperative contrast-enhanced ampullary MDCT. Two radiologists, blinded to pathologic diagnosis of adenocarcinoma subtype, evaluated the presence of seven MDCT features independently. MDCT findings and ampullary adenocarcinoma subtypes were correlated using chi-square and Fisher exact tests. Interobserver agreement was evaluated using the Cohen kappa statistic. RESULTS: When evaluated with ampullary MDCT, the intestinal and pancreatobiliary subtypes were significantly different in terms of lesion morphology (p < 0.0001), papillary shape (p < 0.0001), common bile duct (CBD) infiltration and dilatation (p = 0.003 and p = 0.0004, respectively), duodenopancreatic groove infiltration (p = 0.0009), and pancreaticoduodenal artery involvement (p = 0.004). Pancreatobiliary subtype tumors were more often infiltrative in morphology (18/18) and showed retracted papilla (14/18), CBD (18/18) and main pancreatic duct (MPD) infiltration (12/18), dilated CBD (18/18) and MPD (13/18), fixed duodenopancreatic groove appearance (15/18), and pancreaticoduodenal artery involvement (12/18). Intestinal subtype carcinomas were more frequently nodular (14/14) and had a bulging papilla (13/14), a free duodenopancreatic groove appearance (11/14), and no pancreaticoduodenal artery involvement (2/14). When all features were taken into account, MDCT showed sensitivity of 85.7% and specificity of 83.3% in differentiating intestinal and pancreatobiliary subtype tumors. Accuracy, positive predictive value, and negative predictive value of MDCT were 84.4%, 80%, and 88.2%, respectively. Interobserver agreement was almost perfect for the presence of each imaging feature (κ > 0.8). CONCLUSION: Ampullary MDCT can be useful to differentiate pancreatobiliary and intestinal subtypes of ampullary adenocarcinoma preoperatively, provided the duodenum is optimally distended at imaging.

Nonepithelial Neoplasms of the Pancreas: Radiologic-Pathologic Correlation, Part 1--Benign Tumors: From the Radiologic Pathology Archives.

Solid and cystic pancreatic neoplasms are being recognized more frequently with increasing utilization and spatial resolution of modern imaging techniques. In addition to the more common primary pancreatic solid (ductal adenocarcinoma) and cystic neoplasms of epithelial origin, nonepithelial neoplasms of the pancreas may appear as well-defined solid or cystic neoplasms. Most of these lesions have characteristic imaging features, such as a well-defined border, which allows differentiation from ductal adenocarcinoma. Solid masses include neurofibroma, ganglioneuroma, leiomyoma, lipoma, and perivascular epithelioid cell tumor (PEComa). Schwannomas and desmoid tumors can be solid or cystic. Cystic tumors include mature cystic teratoma and lymphangioma. Lipoma, PEComa, and mature cystic teratoma can contain fat, and ganglioneuroma and mature cystic teratoma may contain calcification. Although these unusual benign neoplasms are rare, the radiologist should at least consider them in the differential diagnosis of well-defined lesions of the pancreas. The goal of this comprehensive review is to improve understanding of these rare primary pancreatic mesenchymal tumors.

Pancreatic ductal adenocarcinoma radiology reporting template: consensus statement of the society of abdominal radiology and the american pancreatic association.

Pancreatic ductal adenocarcinoma is an aggressive malignancy with a high mortality rate. Proper determination of the extent of disease on imaging studies at the time of staging is one of the most important steps in optimal patient management. Given the variability in expertise and definition of disease extent among different practitioners as well as frequent lack of complete reporting of pertinent imaging findings at radiologic examinations, adoption of a standardized template for radiology reporting, using universally accepted and agreed on terminology for solid pancreatic neoplasms, is needed. A consensus statement describing a standardized reporting template authored by a multi-institutional group of experts in pancreatic ductal adenocarcinoma that included radiologists, gastroenterologists, and hepatopancreatobiliary surgeons was developed under the joint sponsorship of the Society of Abdominal Radiologists and the American Pancreatic Association. Adoption of this standardized imaging reporting template should improve the decision-making process for the management of patients with pancreatic ductal adenocarcinoma by providing a complete, pertinent, and accurate reporting of disease staging to optimize treatment recommendations that can be offered to the patient. Standardization can also help to facilitate research and clinical trial design by using appropriate and consistent staging by means of resectability status, thus allowing for comparison of results among different institutions.

Nononcologic applications of diffusion-weighted imaging in the gastrointestinal system.

OBJECTIVE: The purpose of this article is to review infectious, inflammatory, and auto-immune-mediated processes in the gastrointestinal system where diffusion-weighted imaging can be helpful as well as pitfalls associated with its use. CONCLUSION: Diffusion-weighted imaging has become an important and widely used tool in abdominal and pelvic MRI, but it has been used primarily for oncologic applications. As more body MRI protocols are routinely including diffusion-weighted imaging, this sequence can be useful in evaluating an increasing number of nononcologic processes.

MR Enterography of the Ileoanal Pouch: Descriptive Radiologic Analysis With Endoscopic and Pathologic Correlation.

OBJECTIVE: The purpose of this study was to describe the MR enterography (MRE) appearance of inflammation of the ileoanal pouch after ileal pouch-anal anastomosis (IPAA) surgery and to correlate it with pouch endoscopic and histopathologic findings. MATERIALS AND METHODS: All MRE studies performed between October 1, 2007, and September 30, 2013, for patients who had previously undergone IPAA (n = 54) were retrieved. After review of medical records, the patients who underwent MRE, pouch endoscopy, and biopsy within 90 days (14 men, 14 women; mean age, 42.2 years; range, 24-67 years) were selected for inclusion in the study. Two blinded MRI radiologists in consensus retrospectively evaluated MRE studies for multiple MRI features. Two MRI scores were then calculated: an active and a composite inflammation score. A gastroenterologist retrospectively reviewed the pouch endoscopic images, and a pathologist reviewed the slides; both of these investigators were blinded. Both MRI scores were correlated with the pouch endoscopic and histopathologic findings. RESULTS: The composite MRI score had strong positive correlation with the endoscopic score (r = 0.61; p = 0.0005) but weak positive correlation with the histopathologic score (r = 0.31; p = 0.10, not statistically significant). The active inflammation MRI score had moderate positive correlation with the endoscopic score (r = 0.57; p = 0.0017) and weak positive correlation with the histopathologic score (r = 0.20; p = 0.31, not statistically significant). An MRI score ≥ 4 indicated the best results, with sensitivity of 86%, specificity of 79%, positive predictive value of 80%, negative predictive value of 85%, and accuracy of 82% for pouch inflammation. A positive likelihood ratio of 4.00 and negative likelihood ratio of 0.18 were obtained. CONCLUSION: In patients who have undergone IPAA surgery, the MRE findings strongly correlate with the pouch endoscopic findings with high sensitivity and positive predictive value for pouch inflammation. Therefore, MRE is a useful noninvasive test performed without ionizing radiation that can be used to evaluate patients with clinical symptoms and possibly alleviate the need for endoscopy in a select patient population.

A Practical Guide to MR Imaging Safety: What Radiologists Need to Know.

Magnetic resonance (MR) imaging can provide critical diagnostic and anatomic information while avoiding the use of ionizing radiation, but it has a unique set of safety risks associated with its reliance on large static and changing magnetic fields, high-powered radiofrequency coil systems, and exogenous contrast agents. It is crucial for radiologists to understand these risks and how to mitigate them to protect themselves, their colleagues, and their patients from avoidable harm and to comply with safety regulations at MR imaging sites. Basic knowledge of MR imaging physics and hardware is necessary for radiologists to understand the origin of safety regulations and to avoid common misconceptions that could compromise safety. Each of the components of the MR imaging unit can be a factor in injuries to patients and personnel. Safety risks include translational force and torque, projectile injury, excessive specific absorption rate, burns, peripheral neurostimulation, interactions with active implants and devices, and acoustic injury. Standards for MR imaging device safety terminology were first issued in 2005 and are required by the U.S. Food and Drug Administration, with devices labeled as "MR safe," "MR unsafe," or "MR conditional." MR imaging contrast agent safety is also discussed. Additional technical and safety policies relate to pediatric, unconscious, incapacitated, or pregnant patients and pregnant imaging personnel. Division of the MR imaging environment into four distinct, clearly labeled zones--with progressive restriction of entry and increased supervision for higher zones--is a mandatory and key aspect in avoidance of MR imaging-related accidents. All MR imaging facilities should have a documented plan to handle emergencies within zone IV, including cardiac arrest or code, magnet quench, and fires. Policies from the authors' own practice are provided for additional reference. Online supplemental material is available for this article.