Does hypointense HCC in the Hepatobiliary Phase at Gadoxetate-Enhanced MRI Predict Recurrence After Surgery? A Systematic Review and Meta-analysis.

RATIONALE AND OBJECTIVES: The aim of the current study was to investigate whether hypointense hepatocellular carcinoma (HCC) in the hepatobiliary phase (HBP) on gadoxetic acid-enhanced MRI at pretreatment is a potential prognostic marker for tumor recurrence within 3 years after surgery conducted for a curative purpose (resection or liver transplantation). MATERIALS AND METHODS: Systematic review was performed in the PubMed, Embase, Cochrane Library, and LILACS databases. Original articles focused on evaluating HCC signal intensity (SI) in HBP, as well as recurrence at least 3 years after surgery were included in the study. Odds ratio (OR) was measured based on the inverse variance method and the random-effects model. The Quality in Prognosis Studies (QUIPS) tool was used to assess the quality of the included articles. RESULTS: Five studies with 718 patients, in total, were analyzed. The odds ratio of disease recurrence in patients with hypointense HCC in the HBP, within 3 years after surgery, was 3.12 times higher than that observed in patients with hyperintense HCC in the HBP (OR 3.12; 95% CI 1.27-7.68; p = 0.01). Heterogeneity was classified as intermediate (I2 = 52%). Articles included in the review overall presented a low risk of bias. CONCLUSION: Hypointense HCC in the HBP on gadoxetic acid-enhanced MRI at pretreatment has increased the likelihood of tumor recurrence in patients subjected to resection or liver transplantation. HCC SI in the HBP is a potential non-invasive imaging biomarker associated with patient prognosis.

Magnetic resonance imaging findings in autoimmune hepatitis: how frequent and reproducible are they?

Objective: To determine the frequency and interobserver reproducibility of the magnetic resonance imaging (MRI) features considered diagnostic for autoimmune hepatitis. Materials and Methods: Two abdominal radiologists, blinded to pathology data, reviewed the MRI examinations of 20 patients with autoimmune hepatitis, looking for liver enhancement, lymphadenopathy, portal hypertension, and chronic liver disease. The pattern of liver fibrosis was categorized as reticular, confluent, or mixed. Interobserver agreement was assessed by calculating intraclass correlation coefficients and kappa statistics. Results: The most common abnormal finding on MRI was surface nodularity (in 85%), followed by liver fibrosis with a reticular pattern (in 80%)-categorized as mild (in 25.0%), moderate (in 43.8%), or severe (in 31.2%)-; heterogeneous liver enhancement (in 65%); splenomegaly (in 60%); caudate lobe enlargement (in 50%); and lymphadenopathy (in 40%). The interobserver agreement was almost perfect for surface nodularity (0.83), ascites (0.89), and liver volume (0.95), whereas it was just slight and fair for the degree of fibrosis and for heterogeneous liver enhancement (0.12 and 0.25, respectively). It was also slight and fair for expanded gallbladder fossa and enlarged preportal space (0.14 and 0.36, respectively), both of which are indicative of chronic liver disease. Conclusion: The interobserver agreement was satisfactory for surface nodularity (the most prevalent abnormal MRI finding), ascites, liver volume, and splenomegaly. Conversely, it was only slight or fair for common but less objective criteria.

Objetivo: Determinar a frequência e reprodutibilidade interobservador das características de imagem por ressonância magnética na hepatite autoimune. Materiais e Métodos: Dois radiologistas abdominais, cegos para dados patológicos, revisaram ressonâncias magnéticas de 20 pacientes com hepatite autoimune quanto ao realce hepático, linfadenopatia, hipertensão portal e doença hepática crônica. A fibrose foi classificada como reticular, confluente ou ambas. A concordância interobservador foi avaliada por coeficientes de correlação intraclasse e estatística kappa. Resultados: O achado anormal mais comum foi nodularidade superficial (85%), seguido de fibrose reticular hepática (80%) ­ leve (25%), moderada (43,8%), grave (31,2%) ­, realce heterogêneo (65%), esplenomegalia (60%), aumento do lobo caudado (50%) e linfadenopatia (40%). A concordância interobservador foi quase perfeita para nodularidade superficial (0,83), ascite (0,89) e volume hepático (0,95); entretanto, foi apenas leve (0,12) e razoável (0,25) para grau de fibrose e realce heterogêneo, respectivamente. Também foi leve (0,14) ou regular (0,36) para achados de doença hepática crônica, como fossa da vesícula biliar expandida e espaço pré-portal alargado, respectivamente. Conclusão: A concordância geral foi satisfatória para nodularidade superficial (achado anormal mais prevalente), ascite, volume hepático e esplenomegalia. Critérios frequentes, porém menos objetivos, tiveram apenas concordância leve a razoável.

The Cecum Revisited: A Multimodality Imaging Case-based Review of Common and Uncommon Cecal Diseases.

A wide range of conditions involving the cecum may be found in patients undergoing imaging work-up for conditions as various as right lower pain, diarrhea, fever, and weight loss. The cecum may be the only area of involvement by a particular disease. However, it may also be affected by a more diffuse process of the gastrointestinal tract or even as part of systemic diseases. Imaging provides an excellent evaluation of the cecal region and its surrounding planes, with an impactful clinical application in multiple scenarios. While typical features in many situations allow establishing a confident diagnosis, there are also challenging entities with overlapping features, making it critical for the radiologist awareness of the whole gamut of these conditions, as well as the ability to correlate imaging findings with other clinical data. Additional challenges to the imaging evaluation include anatomical variations of the cecal position and the absence of proper colonic distention in some cases. This article aims to revisit the spectrum of cross-sectional imaging features of common and uncommon pathologies involving the cecum, ranging from inflammatory and infectious to vascular and neoplastic ones.

Anatomy and Imaging of Accessory Liver Lobes: What Radiologists Should Know.

Although the liver may present a range of congenital anomalies, often involving shape irregularities or the number of lobules, less common variations include the presence of accessory liver lobes (ALL), consisting of a supernumerary lobe of normal hepatic parenchyma in continuity with the liver. This paper reviews the embryology, frequency, anatomy, and types of ALL. Furthermore, we describe computed tomography and magnetic resonance imaging findings in a range of such cases, including those simulating disease or presenting with complications. Knowledge about ALL may facilitate imaging interpretation of such alterations, avoiding inappropriate additional work-up and unnecessary interventions.

Practical Guide for Radiological Diagnosis of Primary and Secondary Sclerosing Cholangitis.

Sclerosing cholangitis comprises a group of conditions that lead to chronic cholestatic disease of the bile ducts, characterized by inflammation, fibrosis, and segmental strictures of the intrahepatic and/or extrahepatic ducts, and can be classified as primary sclerosing cholangitis or secondary sclerosing cholangitis. In this review, we follow a logical step-by-step appraisal of the clinical and radiological findings of the main secondary sclerosing cholangitis groups, finally arriving at the exclusion diagnosis, which is primary sclerosing cholangitis. At the end, a practical guide is provided, aiming to facilitate the radiological approach to this complex group of diseases.

The Ductal Plate From the Inside Out: An Illustrated Review of Fibropolycystic Liver Disease.

Fibropolycystic liver disease is a continuum of disorders that result from insults to the ductal plate at different stages of development and are often associated with each other. Caroli's syndrome, polycystic liver disease, biliary hamartomas, and congenital hepatic fibrosis are included in this complex spectrum that also shows frequent association with renal anomalies, such as polycystic kidney disease and medullary sponge kidney. Choledochal cysts are a controversial point in this topic since they have long been considered part of this spectrum due to morphological similarities, but studies have shown different pathogenesis. This article's purpose is to review these abnormalities through a multimodality radiological perspective offering correlation with its key embryological aspects. Knowing these numerous anomalies and their possible associations may ease an accurate diagnosis and prompt management.

Vaginal cancer: Why should we care? Anatomy, staging and in-depth imaging-based review of vaginal malignancies focusing on MRI and PET/CT.

Vaginal cancer often poses a challenge for clinical and radiological diagnosis, and its risk factors, progression, and treatment are still poorly established. Although vaginal malignancies are rare, even globally, their rates have increased due to the increased access to healthcare and the evolution of screening measures and diagnostic methods. Because the vaginal cavity is a virtual space, it can harbor lesions that often go unnoticed and, not infrequently, diagnosed belatedly. MRI and, more recently, PET/CT are part of the imaging armamentarium that have already been incorporated into the clinical staging and management of gynecological tumors, allowing excellent morphological characterization of the lesion, its topography and relationship with adjacent structures for the investigation of disease dissemination, overcoming limitations of clinical methods, such as speculum examination, usually restricted to observation only of the superficial characteristics of these lesions. Some vaginal neoplasms have characteristic MRI patterns, which, combined with expert knowledge of anatomy, allow identification of local macroscopic details (such as the mucosal, submucosal, and muscle layers). Furthermore, the application of PET/CT, already well established for identifying systemic disease, has a large impact on patient prognosis. The objective of this work is to review the epidemiological aspects of primary vaginal cancers and the imaging patterns of their main histological subtypes based on MRI and PET/CT, with a brief discussion of the local anatomy, oncological staging, and treatment.

Reproducibility of MRI Features of Uterine Leiomyomas: A Study on Interobserver Agreement and Inter-Method Agreement With Surgery.

PURPOSE: To evaluate interobserver agreement in the interpretation of different MRI features of uterine leiomyomas (UL) according to observers' experience, and to assess the inter-method reproducibility (MRI versus surgery) regarding the International Federation of Gynecology and Obstetrics (FIGO) classification. METHODS: Retrospective study including UL patients who underwent MRI and surgical treatment. Four blinded observers (2 vs >10 years of experience) assessed UL regarding dimensions and volume; inner and outer mantles; FIGO classification; vascularization; degeneration; and diffusion-weighted imaging features. Uterine dimensions and volume were calculated. FIGO classification as ascertained by observers was compared to surgical findings. Intraclass correlation coefficient (ICC) estimates were used for interobserver comparison of numerical variables, and kappa statistic for categorical variables. RESULTS: Thirty-five patients (26y-73y) with 61 UL were included in the interobserver analyses, and 31 patients (54 UL) had available data allowing retrospective surgical FIGO classification for assessment of inter-method reproducibility. Both groups of observers had good to excellent agreement in assessing UL (ICC = 0.980-0.994) and uterine volumes (ICC = 0.857-0.914), mantles measurement (ICC = 0.797-0.920), and apparent diffusion coefficient calculation (ICC = 0.787-0.883). There was substantial agreement for both groups regarding FIGO classification (κ = 0.645-0.767). Vascularization, degeneration and restricted diffusion had lower agreement, varying from reasonable to moderate. Inter-method agreement was reasonable (κ = 0.341-0.395). CONCLUSIONS: Interobserver agreement of MRI for UL was higher for quantitative than qualitative features, with a little impact of observers' experience for most features. MRI agreement with surgery was reasonable. Further efforts should be taken to improve interobserver and inter-method reproducibility for MRI in this scenario.

Influence of 5-Alpha Reductase Inhibitors on Prostate Cancer Detection with Magnetic Resonance Imaging: A Matched Cohort Study.

PURPOSE: We evaluated the influence of 5-alpha reductase inhibitors (5-ARIs) on the performance of magnetic resonance imaging (MRI) for detection of Gleason grade group (GG) ≥2 prostate cancer, and on apparent diffusion coefficient (ADC) maps. MATERIALS AND METHODS: This single center, retrospective study included men who had MRI for initial detection or active surveillance of prostate cancer. The study group included 59 men who used for 5-ARIs for ≥12 months, and the control group included 59 men who were matched for both MRI indication and biopsy results. DeLong's test was used to compare the area under the receiver operating characteristic curve (AUC) for detection of GG ≥2 cancer between the groups. Wilcoxon rank sum test was used for comparison of lesions apparent diffusion coefficient (ADC) metrics between the groups. RESULTS: MRI accuracy in the study group (AUC=0.778) was not significantly different compared to the control group (AUC=0.821; 95% CI for difference 0.22-0.13; p=0.636). In the control group, all ADC metrics were lower in lesions with GG ≥2 cancer on biopsy than in those with GG 1 cancer or negative results (p=0.001-0.01). In the study group, this difference was significant only when the mean ADC of the lesions was normalized by the ADC of urine (p=0.044). CONCLUSIONS: Long-term exposure to 5-ARIs does not seem to impair the detection of significant cancer on MRI but may affect the ability of ADC metrics to discriminate between lesions that harbor significant cancer and those that harbor insignificant cancer or benign tissue.

Critical preparedness and operational response actions directed for the acute and post-acute COVID-19 pandemic in Brazil: the experience of a nationwide outpatient healthcare group.

ABSTRACT: While the new Coronavirus Disease 2019 (COVID-19) pandemic rapidly spread across the world, South America was reached later in relation to Asia, Europe and the United States of America (USA). Brazil concentrates now the largest number of cases in the continent and, as the disease speedily progressed throughout the country, prompt and challenging operational strategies had to be taken by institutions caring for COVID-19 and non-COVID-19 patients in order to assure optimal workflows, triage, and management. Although hospitals in the USA, Europe and Asia have shared their experience on this subject, little has been discussed about such strategies in South America or by the perspective of outpatient centers, which are paramount in the radiology field. This article shares the guidelines adopted early in the pandemic by a nationwide outpatient healthcare center composed by a network of more than 200 patient service centers and nearly 2,000 radiologists in Brazil, discussing operational and patient management strategies, staff protection, changes adopted in the fellowship program, and the effectiveness of such measures.

Placental magnetic resonance imaging: normal appearance, anatomical variations, and pathological findings.

Placental magnetic resonance imaging (MRI) has been increasingly requested, especially for the evaluation of suspected cases of placental adhesive disorders, generally known as placenta accreta. Abdominal radiologists need to become familiar with normal placental anatomy, anatomical variations, the current terminology, and major placental diseases that, although rare, are important causes of maternal and fetal morbidity and mortality. The aim of this didactic pictorial essay is to illustrate various findings on placental MRI, as well as to emphasize the importance of communication between radiologists and obstetricians in the search for best practices in the management of the affected patients.

A ressonância magnética placentária tem sido cada vez mais solicitada, sobretudo na avaliação de casos suspeitos de acretismo. Os radiologistas abdominais precisam se familiarizar com a anatomia placentária normal, variações anatômicas, terminologias atuais e principais doenças placentárias que, embora raras, são causas importantes de morbimortalidade materno-fetal. O objetivo deste ensaio é ilustrar, de maneira didática, diferentes achados placentários e enfatizar a importância da comunicação entre radiologistas e obstetras na busca da melhor conduta para as pacientes.

Performance of imaging interpretation, intra- and inter-reader agreement for diagnosis of pelvic endometriosis: comparison between an abbreviated and full MRI protocol.

PURPOSE: To compare the performance of imaging interpretation, intra- and inter-reader agreement between an abbreviated (aMRI) and full (fMRI) MRI protocol for diagnosis of pelvic endometriosis. METHODS: Seventy consecutive fMRI exams performed under suspicion of pelvic endometriosis were selected. Four radiologists (Rd) (1-10 years experience) independently evaluated presence/absence of endometriosis at 9 anatomic sites (AS). The readers evaluated aMRI (coronal T2 TSE volumetric images and axial T1 GRE fat-sat without contrast, extracted from fMRI) and fMRI protocols randomly, with at least 4 weeks interval between readings. The degree of confidence for diagnosis at each AS was evaluated with a 1-3 Likert Scale (1: low; 3: high). Intra- and inter-reader agreement between protocols were evaluated by kappa statistics and took reading experience into account. The gold standard for assessing the performance of imaging interpretation (sensitivity, specificity and accuracy) used a consensus reading of two other Rd (> 15 years experience). RESULTS: There was no significant difference in the accuracy of imaging interpretation between the abbreviated (0.83-0.86) and full (0.83-0.87) protocols (p = 0.15). Intra-reader agreement between protocols ranged from substantial to almost perfect (0.74-0.96). A substantial inter-reader agreement was found for both protocols for readers with similar levels of experience (0.67-0.69) and in the global analysis (0.66 for both protocols). No difference was found in terms of degree of confidence between protocols, for all readers. CONCLUSION: An abbreviated MRI protocol for pelvic endometriosis provided an accuracy of interpretation comparable to that of a complete protocol, with similar degrees of confidence and reproducibility, regardless the level of experience.

Structured MRI reporting increases completeness of radiological reports and requesting physicians' satisfaction in the diagnostic workup for pelvic endometriosis.

PURPOSE: MRI plays an important role in the diagnosis and surgical planning of pelvic endometriosis (PE), and imaging reports should contain all relevant information (completeness). As structured reports are being increasingly utilized, we aimed to evaluate whether structured MRI reporting increases the quality of reports regarding completeness and, consequently, their perceived value by gynecologists, in comparison to free-text reports. We also aimed to compare the diagnostic performance of both formats. METHODS: We retrospectively included 28 consecutive women with histologically proven PE who underwent MRI within one month before surgery. Two abdominal radiologists (Rd1/Rd2, 3y/12y experience), blinded to clinical and surgical data, individually elaborated free-text reports and, four months later, structured reports. Completeness (defined as description of six key anatomical sites deemed essential for surgical planning in a consensus of four-blinded external experts) and diagnostic performance (sensitivity and specificity) by site (histology as reference) were compared between reports using the McNemar test. The satisfaction of gynecologists was compared using the marginal homogeneity test. RESULTS: Structured reporting increased completeness for both Rd1 (rectosigmoid, retrocervical/uterosacral ligament, vagina, and ureter) and Rd2 (vagina, ureter, and bladder) (p < 0.05), without compromising sensitivity or specificity at any of the evaluated sites. Gynecologists' satisfaction was superior with structured reports in most comparisons. CONCLUSION: Structured MRI reports perform better in fully documenting essential features of PE and are similar in terms of diagnostic performance, therefore having higher potential for surgical planning. Gynecologists found them easier to assess and were more satisfied with the information provided by structured reports.

HCC Detection on Surveillance US: Comparing Focused Liver Protocol Using US LI-RADS Technical Guidelines to a General Complete Abdominal US Protocol.

OBJECTIVE: Focused US examinations of the liver in the routine hepatocellular carcinoma (HCC) screening reduce the time spent on evaluating other structures deemed irrelevant to the clinical setting. It is still unknown, however, if such a strategy may additionally improve the frequency of nodules detection. We aimed to assess the impact of an HCC surveillance program in high-risk patients by means of targeted liver US following LI-RADS technical guidelines in comparison to a complete upper abdominal scan. METHODS: In this IRB-approved, single-center, prospective study, patients at high-risk for HCC enrolled from 06/2016 to 09/2019 were randomly assigned to 1 of the 2 institutional protocols: Group A (targeted liver US) or Group B (complete upper abdominal scan). Twenty examiners with similar experience in abdominal US were randomly assigned to perform the examinations exclusively in 1 of the groups (10 in each group). Frequency of hepatic nodules between groups was compared by using Fisher's exact test. RESULTS: Four hundred and sixty-five patients were enrolled, with no significant differences in both groups regarding sex, age, etiology of liver disease, MELD scores, and alpha-fetoprotein levels. A significantly higher frequency of nodules detection was found in Group A (230 patients; 23 nodules detected; 10% of the sample) in comparison to Group B (235 patients; 3 nodules; 1.3% of the sample) (p <.001). Five patients in Group A and 1 in Group B were positive for HCC after full diagnostic work-up. CONCLUSION: Adopting an HCC screening program based on targeted liver US improved the detection of hepatic nodules among high-risk individuals.

Autoimmune hepatitis in practice, from diagnosis to complications: What is the role of imaging? A clinicoradiological review.

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease of unknown origin that can lead to liver cirrhosis, hepatocellular carcinoma (HCC), liver transplantation or death. The diagnosis is performed upon a multifactorial score. Treatment is based on the combination of immunosuppressants and aims at clinical, laboratory and histological remission, the latter being the most difficult to be achieved and proven. The absence of liver inflammation, defined by biopsy, is the main determinant in remission or therapeutic modification. Imaging exams have a limited role in this clinical management and the main findings are those related to chronic liver disease. Imaging's relevance, therefore, lies mainly in helping to exclude overlapping syndromes and in assessing complications related to cirrhosis, such as in screening for HCC. In recent years, however, the radiological literature has been witnessing increasing advances with regard to imaging biomarkers in liver disease, leading some authors to consider a future of virtual liver biopsy performed by magnetic resonance imaging. The present study aims to review the role of imaging in the management of AIH in the light of recent advances in the current literature and to provide an illustrated guide with the main findings described in the disease.

Emergency CT of abdominal complications of ingested fish bones: what not to miss.

Fish bones are the most commonly ingested structures and the most common cause of foreign body perforation of the gastrointestinal tract (GIT). Clinical presentation of foreign body GIT perforation is nonspecific, in many cases with clinical signs of acute abdomen, which can mimic appendicitis, diverticulitis, ulcer peptic disease, and other common inflammatory conditions. Besides, patients commonly do not refer that a fish bone was swallowed. Since this condition is usually not suspected by referring physicians of the emergency department (ED), radiologists play a key role in this diagnosis; the spectrum of these imaging features must be known in order to be accurately reported in the ED.