Pancreatic ductal adenocarcinoma and distal cholangiocarcinoma: a proposal of preoperative diagnostic score for differential diagnosis.

PURPOSE: The differential diagnosis between primary adenocarcinoma of the pancreas head and distal cholangiocarcinoma remains a clinical challenge. Recent studies have shown important differences in terms of survival between these tumors. Therefore, different treatments should be considered, but the preoperative histological diagnosis is still difficult. Aim of this study is to create a preoperative diagnostic score for differential diagnosis between primary pancreatic adenocarcinoma and primary distal cholangiocarcinoma. METHODS: One hundred eighty consecutive patients who underwent pancreaticoduodenectomy at Sapienza University of Rome from January 2010 to December 2019 were retrospectively analyzed. Inclusion criteria were pancreatic or biliary histologic origin obtained by definitive postoperative histological examination. Exclusion criteria were diagnosis of ampullary carcinoma, non-ampullary duodenal adenocarcinoma, pancreatic metastasis, and benign disease. One hundred one patients were considered eligible for the retrospective study. Preoperative biological, clinical, and radiological parameters were considered. RESULTS: CRP > 10 mg/dL (p = 0.001), modified Glasgow Prognostic Score 2 (p = 0.002), albumin < 35 g/L (p = 0.05), CA 19-9 > 230 U/mL (p = 0.001), and Wirsung diameter > 3 mm (p < 0.001) were significant at univariate logistic analysis. Multivariate logistic analysis has shown that parameters independently associated with primary pancreatic adenocarcinoma were CRP > 10 mg/dL (p = 0.012), CA 19-9 > 230 U/mL (p = 0.043), and diameter of the Wirsung > 3 mm (p = 0.005). Through these parameters, a diagnostic score has been developed to predict a primary pancreatic adenocarcinoma when > 1 and a primary distal cholangiocarcinoma when < 1. CONCLUSION: This feasible and low-cost diagnostic score could have a potential impact to differentiate pancreatic cancer histologic origin and to improve target therapeutic strategy.

Role of CT angiography in detecting acute pulmonary embolism associated with COVID-19 pneumonia.

PURPOSE: Recently coronavirus disease (COVID-19) caused a global pandemic, characterized by acute respiratory distress syndrome (ARDS). The aim of our study was to detect pulmonary embolism (PE) in patients with severe form of COVID-19 infection using pulmonary CT angiography, and its associations with clinical and laboratory parameters. METHODS: From March to December 2020, we performed a prospective monocentric study collecting data from 374 consecutive patients with confirmed SARS-CoV-2 infection, using real-time reverse-transcriptase polymerase-chain-reaction (rRT-PCR) assay of nasopharyngeal swab specimens. We subsequently selected patients with at least two of the following inclusion criteria: (1) severe acute respiratory symptoms (such as dyspnea, persistent cough, fever > 37.5 °C, fatigue, etc.); (2) arterial oxygen saturation ≤ 93% at rest; (3) elevated D-dimer (≥ 500 ng/mL) and C-reactive protein levels (≥ 0.50 mg/dL); and (4) presence of comorbidities. A total of 63/374 (17%) patients met the inclusion criteria and underwent CT angiography during intravenous injection of iodinated contrast agent (Iomeprol 400 mgI/mL). Statistical analysis was performed using Wilcoxon rank-sum and Chi-square tests. RESULTS: About, 26/60 patients (40%) were found positive for PE at chest CT angiography. In these patients, D-dimer and CRP values were significantly higher, while a reduction in SaO2 < 93% was more common than in patients without PE (P < 0.001). Median time between illness onset and CT scan was significantly longer (15 days; P < 0.001) in patients with PE. These were more likely to be admitted to the Intensive Care Unit (19/26 vs. 11/34 patients; P < 0.001) and required mechanical ventilation more frequently than those without PE (15/26 patients vs. 9/34 patients; P < 0.001). Vascular enlargement was significantly more frequent in patients with PE than in those without (P = 0.041). CONCLUSIONS: Our results pointed out that patients affected by severe clinical features of COVID-19 associated with comorbidities and significant increase of D-dimer levels developed acute mono- or bi-lateral pulmonary embolism in 40% of cases. Therefore, the use of CT angiography rather than non-contrast CT should be considered in these patients, allowing a better evaluation, that can help the management and improve the outcomes.

Society of Abdominal Radiology (SAR) and European Society of Urogenital Radiology (ESUR) joint consensus statement for MR imaging of placenta accreta spectrum disorders.

OBJECTIVES: This study was conducted in order to establish the joint Society of Abdominal Radiology (SAR) and European Society of Urogenital Radiology (ESUR) guidelines on placenta accreta spectrum (PAS) disorders and propose strategies to standardize image acquisition, interpretation, and reporting for this condition with MRI. METHODS: The published evidence-based data and the opinion of experts were combined using the RAND-UCLA Appropriateness Method and formed the basis for these consensus guidelines. The responses of the experts to questions regarding the details of patient preparation, MRI protocol, image interpretation, and reporting were collected, analyzed, and classified as "recommended" versus "not recommended" (if at least 80% consensus among experts) or uncertain (if less than 80% consensus among experts). RESULTS: Consensus regarding image acquisition, interpretation, and reporting was determined using the RAND-UCLA Appropriateness Method. The use of a tailored MRI protocol and standardized report was recommended. CONCLUSIONS: A standardized imaging protocol and reporting system ensures recognition of the salient features of PAS disorders. These consensus recommendations should be used as a guide for the evaluation of PAS disorders with MRI. KEY POINTS: • MRI is a powerful adjunct to ultrasound and provides valuable information on the topography and depth of placental invasion. • Consensus statement proposed a common lexicon to allow for uniformity in MRI acquisition, interpretation, and reporting of PAS disorders. • Seven MRI features, namely intraplacental dark T2 bands, uterine/placental bulge, loss of low T2 retroplacental line, myometrial thinning/disruption, bladder wall interruption, focal exophytic placental mass, and abnormal vasculature of the placental bed, reached consensus and are categorized as "recommended" for diagnosing PAS disorders.

Endometrial Cancer MRI staging: Updated Guidelines of the European Society of Urogenital Radiology.

OBJECTIVES: To update the 2009 ESUR endometrial cancer guidelines and propose strategies to standardize image acquisition, interpretation and reporting for endometrial cancer staging with MRI. METHODS: The published evidence-based data and the opinion of experts were combined using the RAND-UCLA Appropriateness Method and formed the basis for these consensus guidelines. The responses of the experts to 81 questions regarding the details of patient preparation, MR imaging protocol, image interpretation and reporting were collected, analysed and classified as "RECOMMENDED" versus "NOT RECOMMENDED" (if at least 80% consensus among experts) or uncertain (if less than 80% consensus among experts). RESULTS: Consensus regarding patient preparation, MR image acquisition, interpretation and reporting was determined using the RAND-UCLA Appropriateness Method. A tailored MR imaging protocol and a standardized report were recommended. CONCLUSIONS: These consensus recommendations should be used as a guide for endometrial cancer staging with MRI. KEY POINTS: • MRI is recommended for initial staging of endometrial cancer. • MR imaging protocol should be tailored based on the risk of lymph node metastases. • Myometrial invasion is best assessed using combined axial-oblique T2WI, DWI and contrast-enhanced imaging. • The mnemonic "Clinical and MRI Critical TEAM" summarizes key elements of the standardized report.

New-onset ulcerative colitis in pregnancy associated to toxic megacolon and sudden fetal decompensation: Case report and literature review.

Ulcerative colitis (UC) is a chronic inflammatory disease rarely arising during gestation. Because the available information is based on case reports or small retrospective studies, diagnosis may be difficult and treatment is still controversial. A case of toxic megacolon developing in late pregnancy associated to a sudden fetal decompensation is described. Diagnostic and clinical topics of acute UC onset in pregnancy are debated.A primipara, 34 years old, 33/0 weeks of gestation, was admitted with a diagnosis of preterm labor, associated to acute bloody diarrhea (up to 10 daily motions) and cramping abdominal pain. A diagnosis of new-onset early-stage UC was made by sigmoidoscopy. An intensive care regimen including hydrocortisone, antibiotics and parenteral nutrition was immediately started. Magnetic resonance imaging of maternal abdomen, fostered by the worsening patient conditions, evidenced dilatation of the entire colon and a severely hampered of fetal muscular tone.Toxic megacolon complicated by superimposed Clostridium difficile infection was associated to a sudden fetal decompensation diagnosed by chance during maternal abdominal magnetic resonance imaging. An emergency cesarean section was mandatory. According to a senior surgeon's decision, total colectomy was not immediately performed following cesarean section with reference to the absence of colonic perforation. We obtained a good short-term maternal outcome and an uncomplicated neonatal course. Counseling of those patients must be focused on timely and multidisciplinary intervention in order to improve the course of maternal disease and to prevent fetal distress.

Detection of Crohn's disease with diffusion images versus contrast-enhanced images in pediatric using MR enterography with histopathological correlation.

The purpose of this study was to determine whether MRE performed with diffusion-weighted imaging (DWI) sequences is comparable to contrast-enhanced MRE in the detection of active small-bowel inflammation in pediatric patients with Crohn's disease (CD). We included in our study 68 patients with diagnosis of CD between April 2015 and June 2018 that underwent MRE examination. Examination protocol includes coronal and axial FISP, T2-w half-Fourier RARE and DWI sequences, a baseline coronal T1-w fat-saturated ultrafast (GRE) sequence followed by contrast 3D T1-w GRE. All images were assessed by two radiologists who graded each of bowel segments for the presence of inflammation on a four-point confidence scale on the basis of wall thickening and wall signal on DWI and ADC maps and comparing their results with post-contrast images. When considering all bowel segments, we found 41 true positive and 25 true negative on DWI. One false positive case corresponded to the absence of inflammatory histopathology changes at the level of the terminal ileum in a 15-year-old male, and one false negative case was in a 10-year-old female with only jejunal lesion. The corresponding sensitivity, specificity, PPV, NPV and accuracy were 97.6% (95% CI 67.7-99.7), 96.1% (95% CI 66.7-98.5), 97.6% (95% CI 70.8-98.4), 96.1% (95% CI 64.2-90.6) and 97% (95% CI 84.2-97.5), respectively. Analyzing the gadolinium-enhanced set, 35 true positive and 25 true negative results were found. One false positive case was found, and it was the same as with DWI. The corresponding sensitivity, specificity, PPV, NPV and accuracy were 83.3% (95% CI 65.9-86.7), 96.1% (95% CI 68.7-88.9), 97.2% (95% CI 84.3-98.7), 78.1% (95% CI 27.9-72.1) and 88.2% (95% CI 41.2-85.6), respectively. Sensitivity for the detection of active IBD lesion was significantly better with DWI than with CE-T1-w imaging (p = 0.002), whereas the specificity was similar (p = 0.743). Our study has shown that DWI sequences have a high accuracy in detecting the bowel segment affected by CD. These results emphasize the utility to include the DWI/ADC in standard MR enterography protocols and suggest that DWI could replace T1-weighted post-contrast sequences.

To evaluate the feasibility of magnetic resonance imaging in predicting unusual site ectopic pregnancy: a retrospective cohort study.

OBJECTIVE: To evaluate the accuracy of pelvic MRI in the diagnosis of unusual ectopic pregnancy (EP), when ultrasound (US) examination is inconclusive. METHODS: We retrospectively reviewed the medical records of 150 patients with suspected EP. Clinical, US and MRI features of 15 unusual EPs were analysed. Two radiologists independently reviewed each case resolving by consensus any diagnostic discrepancy. Interobserver agreement was assessed using the Cohen κ test. RESULTS: MRI displayed a gestational sac-like structure surrounded by a thick wall in all cases. The thick wall displayed hyperintensity in 41 %, isointensity in 35 % and hypointensity in 24 % of cases on T1-weighted images. Diffusion- and fat saturation T1-weighted images were the most accurate sequences, as they enabled identification of 15/15 and 14/15 patients, respectively. Although US was false negative in detecting cervical and uterine infiltration underlying the caesarean scar, MRI was able to identify the invasion. Interobserver agreement was very good for all sequences (κ=0.892-1.0). CONCLUSIONS: MRI plays an important role in the early diagnosis of unusual EP. It should be considered after negative US findings, providing accurate evaluation of the site and the possible infiltration of these lesions, which help in the management of these patients. KEY POINTS: • MRI is being increasingly used as a problem-solving modality in ectopic pregnancy. • MRI plays an important role in early diagnosis of unusual ectopic pregnancy. • Knowledge of MRI features in EP is essential to determinate appropriate management.

Magnetic resonance imaging of pelvic floor dysfunction - joint recommendations of the ESUR and ESGAR Pelvic Floor Working Group.

OBJECTIVE: To develop recommendations that can be used as guidance for standardized approach regarding indications, patient preparation, sequences acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for diagnosis and grading of pelvic floor dysfunction (PFD). METHODS: The technique included critical literature between 1993 and 2013 and expert consensus about MRI protocols by the pelvic floor-imaging working group of the European Society of Urogenital Radiology (ESUR) and the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) from one Egyptian and seven European institutions. Data collection and analysis were achieved in 5 consecutive steps. Eighty-two items were scored to be eligible for further analysis and scaling. Agreement of at least 80 % was defined as consensus finding. RESULTS: Consensus was reached for 88 % of 82 items. Recommended reporting template should include two main sections for measurements and grading. The pubococcygeal line (PCL) is recommended as the reference line to measure pelvic organ prolapse. The recommended grading scheme is the "Rule of three" for Pelvic Organ Prolapse (POP), while a rectocele and ARJ descent each has its specific grading system. CONCLUSION: This literature review and expert consensus recommendations can be used as guidance for MR imaging and reporting of PFD. KEY POINTS: • These recommendations highlight the most important prerequisites to obtain a diagnostic PFD-MRI. • Static, dynamic and evacuation sequences should be generally performed for PFD evaluation. • The recommendations were constructed through consensus among 13 radiologists from 8 institutions.

ESUR recommendations for MR imaging of the sonographically indeterminate adnexal mass: an update.

An update of the 2010 published ESUR recommendations of MRI of the sonographically indeterminate adnexal mass integrating functional techniques is provided. An algorithmic approach using sagittal T2 and a set of transaxial T1 and T2WI allows categorization of adnexal masses in one of the following three types according to its predominant signal characteristics. T1 'bright' masses due to fat or blood content can be simply and effectively determined using a combination of T1W, T2W and FST1W imaging. When there is concern for a solid component within such a mass, it requires additional assessment as for a complex cystic or cystic-solid mass. For low T2 solid adnexal masses, DWI is now recommended. Such masses with low DWI signal on high b value image (e.g. > b 1000 s/mm2) can be regarded as benign. Any other solid adnexal mass, displaying intermediate or high DWI signal, requires further assessment by contrast-enhanced (CE)T1W imaging, ideally with DCE MR, where a type 3 curve is highly predictive of malignancy. For complex cystic or cystic-solid masses, both DWI and CET1W-preferably DCE MRI-is recommended. Characteristic enhancement curves of solid components can discriminate between lesions that are highly likely malignant and highly likely benign. KEY POINTS: • MRI is a useful complementary imaging technique for assessing sonographically indeterminate masses. • Categorization allows confident diagnosis in the majority of adnexal masses. • Type 3 contrast enhancement curve is a strong indicator of malignancy. • In sonographically indeterminate masses, complementary MRI assists in triaging patient management.

Are Second Trimester Apparent Diffusion Coefficient Values of the Short Uterine Cervix Associated with Impending Preterm Delivery?

Purpose To prospectively determine whether the apparent diffusion coefficient (ADC) of the cervix is associated with preterm delivery in asymptomatic patients with a sonographic cervical length of 15 mm or less and positive fetal fibronectin test results between 23 and 28 weeks of gestation. Materials and Methods The institutional review board approved this prospective hypotheses-generating study. A total of 30 pregnant women (mean gestational age, 26 weeks) with a sonographic short cervix (≤15 mm) underwent pelvic 1.5-T magnetic resonance (MR) imaging. Oblique sagittal diffusion-weighted images were obtained with b values of 0, 400, and 800 sec/mm(2). ADC values at MR imaging of the subglandular and stromal cervix and the difference between both were correlated to the interval to delivery. Receiver operating characteristic curve analysis was performed to obtain sensitivity and specificity of ADC values in association with delivery within 7 days. Results Eight (27%) of 30 patients delivered within 6 or 7 days after MR imaging (impending delivery group), and 22 (73%) of 30 patients delivered between 18 and 89 days after imaging (mean, 55 days) (late delivery group). Mean subglandular ADC and mean ADC difference were higher (P < .001) in patients with impending delivery than in those with late delivery ([2406.3 ± 166.0] × 10(-6) mm(2)/sec vs [1708.9 ± 108.1] × 10(-6) mm(2)/sec and [657.3 ± 129.9] × 10(-6) mm(2)/sec vs [69.2 ± 70.2] × 10(-6) mm(2)/sec, respectively). Subglandular ADC inversely correlated with the interval between MR imaging and delivery (r = -0.75). Receiver operating characteristic curve analysis of subglandular ADC revealed 100% sensitivity (95% confidence interval: 63.1, 100) and 100% specificity (95% confidence interval: 84.6, 100) in association with impending delivery with a 1921 × 10(-6) mm(2)/sec threshold. Stromal ADC and sonographic cervical length showed no difference between groups (P = .072 and P = .511, respectively). Conclusion Cervical subglandular ADC at MR imaging is associated with impending preterm birth in patients with a short sonographic cervix. (©) RSNA, 2016.

Diagnosis of Small-Bowel Diseases: Prospective Comparison of Multi-Detector Row CT Enterography with MR Enterography.

PURPOSE: To prospectively compare the accuracies of computed tomographic (CT) enterography and magnetic resonance (MR) enterography for the detection and characterization of small-bowel diseases. MATERIALS AND METHODS: The institutional review board approved the study protocol, and informed consent was obtained from all participants. From June 2009 to July 2013, 150 consecutive patients (81 men and 69 women; mean age, 38.8 years; range, 18-74 years), who were suspected of having a small-bowel disease on the basis of clinical findings and whose previous upper and lower gastrointestinal endoscopy findings were normal, underwent CT and MR enterography. Two independent readers reviewed CT and MR enterographic images for the presence of small-bowel diseases, for differentiating between inflammatory and noninflammatory diseases, and for extraenteric complications. The histopathologic findings of surgical (n = 23) and endoscopic (n = 32) biopsy specimens were used as the reference standard; the results of video-capsule endoscopy (n = 36) and clinical follow-up (n = 59) were used only to confirm the absence of small-bowel disease. RESULTS: MR and CT enterography were successfully performed in all 150 patients. Overall sensitivity, specificity, and accuracy, respectively, in identifying patients with small-bowel lesions were 75.9% (41 of 54), 94.8% (91 of 96), and 88.0% (132 of 150) for CT enterography and 92.6% (50 of 54), 99.0% (95 of 96), and 96.7% (145 of 150) for MR enterography. The sensitivity of MR enterography was significantly higher than that of CT enterography for the detection of both overall small-bowel diseases (P = .0159) and neoplastic diseases (P = .0412) but not for the detection of inflammatory diseases (P > .99) or noninflammatory and nonneoplastic diseases (P = .6171). CONCLUSION: MR enterography is more accurate than CT enterography in the detection of small-bowel diseases; MR enterography was more accurate in detecting neoplastic diseases in particular.

Errors in imaging the pregnant patient with acute abdomen.

Pregnant women with an acute abdomen present a critical issue due to the necessity for an immediate diagnosis and treatment; in fact, a diagnostic delay could worsen the outcome for both the mother and the fetus. There is evidence that emergencies during pregnancy are subject to mismanagement; however, the percentage of errors in the diagnosis of emergencies in pregnancy has not been studied in depth. The purpose of this article is to review the most common imaging error emergencies. The topics covered are divided into gynecological and non-gynecological entities and, for each pathology, possible errors have been dealt with in the diagnostic pathway, the possible technical errors in the exam execution, and finally the possible errors in the interpretation of the images. These last two entities are often connected owing to a substandard examination, which can cause errors in the interpretation. Consequently, the systemization of errors reduces the possibility of reoccurrences in the future by providing a valid approach in helping to learn from these errors.

Breast cancer or metastasis? An unusual case of metastatic malignant pleural mesothelioma to the breast.

BACKGROUND: Metastases to the breast from extramammary malignancies are very rare, and ruling out the diagnosis of primary breast tumor is important in order to decide on clinical management and predict prognosis. CASE PRESENTATION: Clinical examination revealed in a 49-year-old hairdresser a 3-cm hard lump adherent to the underlying layers in the right breast. Trucut biopsy was performed. Histology showed a solid proliferation of medium-sized neoplastic polygonal cells. Immunohistochemical analysis showed tumor cells diffusely positive for cytokeratin 8/18 and calretinin and focally positive for cytokeratin 5/6 and Wilms' tumor 1, e-cadherin, and human bone marrow endothelial-1. Estrogen receptors and progesterone receptors were negative. The final diagnosis was metastatic epithelioid malignant pleural mesothelioma. CONCLUSIONS: Immunohistochemistry is an important tool for a conclusive diagnosis of malignant pleural mesothelioma. Owing to the degree of histological and immunohistochemical overlap, a high level of clinical suspicion is essential in order to avoid unnecessary mutilating surgery.

Transabdominal ultrasound-guided injection of methotrexate in the treatment of ectopic interstitial pregnancies.

PURPOSE: In a retrospective observational study, we evaluated the feasibility and safety of medical therapy with transabdominal ultrasound-guided injection of methotrexate (MTX) into the gestational sac (GS) in patients with interstitial ectopic pregnancies. METHODS: Fourteen interstitial ectopic pregnancies were treated with transabdominal ultrasound-guided injection of MTX (25 mg). All patients were hemodynamically stable. In all patients, the 10-cm distance between the GS and vaginal fornices was ≥10 cm, making transvaginal injection difficult. To evaluate feasibility and safety of the procedure, we assessed complications clinically and with imaging during a 1-year follow-up. RESULTS: In all 14 patients, MTX injected locally into the GS successfully terminated the interstitial pregnancy, thereby avoiding surgery. There was no complications during follow-up. CONCLUSIONS: The successful outcome in our patients suggests that the transabdominal route is feasible and safe as a nonsurgical option for terminating an ectopic interstitial pregnancy in patients in whom the transvaginal route is contraindicated or difficult, provided the patients are properly selected and operators have sufficient experience with the technique.

68Ga-PSMA PET/CT in Recurrent Prostate Cancer after Radical Prostatectomy Using PSMA-RADS Version 2.0.

BACKGROUND: 68Ga-PSMA PET/CT is superior to standard-of-care imaging for detecting regional and distant metastatic recurrent prostate cancer. The objective of our study was to evaluate the performance of 68Ga-PSMAPET/CT in our patient population, using the new PSMA-RADS version 2.0. METHODS: A total of 128 patients scanned with 68Ga-PSMA PET/CT for detection of recurrence after RP were analyzed with PSMA-RADS version 2.0. For the analysis of the detection rate, categories PSMA-RADS 3 to 5 were considered as "positive for malignancy" and 1-2 as "negative". RESULTS: According to PSMA-RADS v2.0, we classified patients as follows: 23 patients without PSMA-RADS because they were negative; PSMA-RADS 1: 10 patients; PSMA-RADS 2: 4 patients; PSMA-RADS 3A: 11 patients; PSMA-RADS 3B: 2 patients; PSMA-RADS 3C: 2 patients; PSMA-RADS 3D: 2 patients; PSMA-RADS 4: 13 patients; PSMA-RADS 5: 61 patients. CONCLUSIONS: The overall detection rate of 68Ga-PSMA PET/CT was 71%. By dividing the patients into fourgroups according to PSA level before examination, we obtained the following detection rates: PSA < 0.2 ng/mL 38%; 0.2 ≤ PSA < 0.5 ng/mL 57%; 0.5 ≤ PSA ≤ 1 ng/mL 77%; and PSA > 1 ng/mL 95%. CONCLUSION: Using PSMA-RADS version 2.0, we obtained detection rate values comparable with recent literature both in absolute terms and in relation to different PSA levels.

Acute abdominal and pelvic pain in pregnancy: ESUR recommendations.

Acute abdominal pain in pregnancy presents diagnostic and therapeutic challenges. Standard imaging techniques need to be adapted to reduce harm to the fetus from X-rays due to their teratogenic and carcinogenic potential. Ultrasound remains the primary imaging investigation of the pregnant abdomen. Magnetic resonance imaging (MRI) has been shown to be useful in the diagnosis of gynaecological and obstetric problems during pregnancy and in the setting of acute abdomen during pregnancy. MRI overcomes some of the limitations of ultrasound, mainly the size of the gravid uterus. MRI poses theoretical risks to the fetus and care must be taken to minimise these with the avoidance of contrast agents. This article reviews the evolving imaging and clinical literature on appropriate investigation of acute abdominal and pelvic pain during established intrauterine pregnancy, addressing its common causes. Guidelines based on the current literature and on the accumulated clinico-radiological experience of the European Society of Urogenital Radiology (ESUR) working group are proposed for imaging these suspected conditions.

MR imaging of the placenta: what a radiologist should know.

Imaging of the placenta can have a profound impact on patient management, owing to the morbidity and mortality associated with various placental conditions. Placental conditions affecting the mother and fetus include molar pregnancies, placental hematoma, abruption, previa, accreta, vasa previa, chorioangioma, and retained products of conception. Although uncommon, abnormalities of the placenta are important to recognize owing to the potential for maternal and fetal morbidity and mortality. Sonography remains the first imaging modality for evaluation of the placenta. Magnetic resonance (MR) imaging has many unique properties that make it well-suited for imaging of the placenta: the multi-planar capabilities, the improved tissue contrast that can be obtained using a variety of pulse sequences and parameters and the lack of ionizing radiation; MR imaging can be of added diagnostic value when further characterization is required. In this article, we review the appearances and the role of MRI in diagnosis and management of these conditions. We present our clinical perspective on diagnosing these challenging problems with MRI and review the imaging findings that can lead to a correct diagnosis.

CT and MR enterography in evaluating small bowel diseases: when to use which modality?

MR and CT techniques optimized for small bowel imaging are playing an increasing role in the evaluation of small bowel disorders. Several studies have shown the advantages of these techniques over traditional barium fluoroscopic examinations due to improvements in spatial and temporal resolution combined with improved bowel distending agents. The preference of MR vs. CT has been geographical and based on expertise and public policy. With the increasing awareness of radiation exposure, there has been a more global interest in implementing techniques that either reduce or eliminate radiation exposure. This is especially important in patients with chronic diseases such as inflammatory bowel disease who may require multiple studies over a lifetime or in studies that require sequential imaging time points such as in assessment of gastrointestinal motility. MRI has many properties that make it well suited to imaging of the small bowel: the lack of ionizing radiation, the improved tissue contrast that can be obtained by using a variety of pulse sequences, and the ability to perform real time functional imaging. Moreover, MR modalities allow visualization of the entire bowel, without overlapping bowel loops, as well as the detection of both intra- and extraluminal abnormalities.The intra- and extraluminal MR findings, combined with contrast enhancement and functional information, help to make an accurate diagnosis and consequently characterize small bowel diseases.