Diagnostic accuracy of an uncorrected native T1 mapping sequence for liver fibrosis and inflammation in autoimmune hepatitis: a prospective study using histopathology as reference standard.

PURPOSE: There is an unmet clinical need for non-invasive imaging biomarkers that could replace liver biopsy in the management of patients with autoimmune hepatitis (AIH). In this study, we sought to evaluate the diagnostic accuracy of a simple uncorrected, non-contrast T1 mapping for detecting fibrosis and inflammation in AIH patients using histopathology as a reference standard. MATERIAL AND METHODS: Over 3 years, 33 patients with AIH were prospectively studied using a multiparametric liver MRI protocol which included T1 mapping. Biopsies were performed up to 3 months before imaging, and a standardized histopathological score for fibrosis (F0-F4) and inflammatory activity (PPA0-4) was used as a reference. Statistical analysis included independent t test, Mann-Whitney U-test, and ROC (receiver operating characteristic) analysis. RESULTS: T1 mapping values were significantly higher in patients with advanced fibrosis (F0-2 vs. F3-4; p < 0.015), significant fibrosis (F0-1 vs. F2-4; p < 0.005), and significant inflammatory activity (PPA 0-1 vs. PPA 2-4 p = 0.048). Moreover, the technique demonstrated a good diagnostic performance in detecting significant (AUC 0.856) and advanced fibrosis (AUC 0.835), as well as significant inflammatory activity (AUC 0.763). CONCLUSION: A rapid, simple, uncorrected, non-contrast T1 mapping sequence showed satisfactory diagnostic performance in comparison with histopathology for detecting significant tissue inflammation and fibrosis in AIH patients, being a potential non-invasive imaging biomarker for monitoring disease activity in such individuals.

Advanced Magnetic Resonance Imaging for Detection of Liver Fibrosis and Inflammation in Autoimmune Hepatitis: A State-of-the-Art Review.

Autoimmune hepatitis is a rare chronic liver disease, associated with a high level of morbidity and high mortality; approximately 40% of patients with severe untreated disease die within 6 months of diagnosis. It should be treated to achieve complete biochemical and histologic resolution of the disease using corticosteroids and immunosuppression to prevent further progression to cirrhosis. The use of invasive liver biopsy is recommended for the staging and assessment of inflammation and fibrosis for treatment decision-making in the face of an unsatisfactory response or clinical remission, including being a determinant for withdrawal of immunosuppression. On the other hand, liver biopsy is invasive, costly, and not free of complications. It also has potential sampling error and poor interobserver agreement. The limitations of liver biopsy highlight the importance of developing new imaging biomarkers that allow accurate and non-invasive assessment of autoimmune hepatitis in terms of liver inflammation and fibrosis, developing the virtual biopsy concept. Therefore, we review the state-of-the-art of Magnetic Resonance Imaging sequences for the noninvasive evaluation of autoimmune hepatitis, including historical advances and future directions.

Common and Uncommon Gestational Complications in Radiological Practice: An Overview.

Gestational complications are common in radiological practice and can be identified and evaluated using various imaging methods. Each complication typically presents with specific imaging features; however, there is a lack of comprehensive literature that consolidates this information to facilitate a diagnostic algorithm and focused study. In this context, this review aims to revisit the theoretical basis of differentials in pregnancy-related complications, discussing classic imaging features and providing examples of key features for each diagnosis. The focus is on essential information for accurate diagnosis, emphasizing the role of radiologists in contributing to better outcomes.

Imaging Prognostic Biomarkers in Hepatocellular Carcinoma: A Comprehensive Review.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide with its incidence on the rise globally. This paper provides a comprehensive review of prognostic imaging markers in HCC, emphasizing their role in risk stratification and clinical decision-making. We explore quantitative and qualitative criteria derived from imaging studies, such as computed tomography (CT) and magnetic resonance imaging (MRI), which can offer valuable insights into the biological behavior of the tumor. While many of these markers are not yet widely integrated into current clinical guidelines, they represent a promising future direction for approaching this highly heterogeneous cancer. However, standardization and validation of these markers remain important challenges. We conclude by emphasizing the importance of ongoing research to enhance clinical practices and improve outcomes for patients with HCC.

Evaluation of colon cancer prognostic factors by CT and MRI: an up-to-date review.

Colorectal cancer (CRC) is a significant global health concern. Prognostication of CRC traditionally relies on the Union for International Cancer Control (UICC) and American Joint Committee on Cancer (AJCC) TNM staging classifications, yet clinical outcomes often vary independently of stage. Despite similarities, rectal and colon cancers are distinct in their diagnostic methodologies and treatments, with MRI and CT scans primarily used for staging rectal and colon cancers, respectively. This paper examines the challenges in accurately assessing prognostic factors of colon cancer such as primary tumor extramural extension, retroperitoneal surgical margin (RSM) involvement, extramural vessel invasion (EMVI), and lymph node metastases through preoperative CT and MRI. It highlights the importance of these factors in risk stratification, treatment decisions, and surgical planning for colon cancer patients. Advancements in imaging techniques are crucial for improving clinical management and optimizing patient outcomes, underscoring the necessity for ongoing research to refine diagnostic methods and incorporate novel findings into practice.

Magnetic resonance imaging findings in autoimmune hepatitis: how frequent and reproducible are they? / Achados de imagem por ressonância magnética na hepatite autoimune: quão frequentes e reprodutíveis são eles?

Abstract 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.

Resumo 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.

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.

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.

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.

Pre-treatment MRI tumor features and post-treatment mammographic findings: may they contribute to refining the prediction of pathologic complete response in post-neoadjuvant breast cancer patients with radiologic complete response on MRI?

PURPOSE: Radiologic complete response (rCR) in breast cancer patients after neoadjuvant chemotherapy (NAC) does not necessarily correlate with pathologic complete response (pCR), a marker traditionally associated with better outcomes. We sought to verify if data extracted from two important steps of the imaging workup (tumor features at pre-treatment MRI and post-treatment mammographic findings) might assist in refining the prediction of pCR in post-NAC patients showing rCR. METHODS: A total of 115 post-NAC women with rCR on MRI (2010-2016) were retrospectively assessed. Pre-treatment MRI (lesion morphology, size, and distribution) and post-treatment mammographic findings (calcification, asymmetry, mass, architectural distortion) were assessed, as well as clinical and molecular variables. Bivariate and multivariate analyses evaluated correlation between such variables and pCR. Post-NAC mammographic findings and their correlation with ductal in situ carcinoma (DCIS) were evaluated using Pearson's correlation. RESULTS: Tumor distribution at pre-treatment MRI was the only significant predictive imaging feature on multivariate analysis, with multicentric lesions having lower odds of pCR (p = 0.035). There was no significant association between tumor size and morphology with pCR. Mammographic residual calcifications were associated with DCIS (p = 0.009). The receptor subtype remained as a significant predictor, with HR-HER2 + and triple-negative status demonstrating higher odds of pCR on multivariate analyses. CONCLUSIONS: Multicentric lesions on pre-NAC MRI were associated with a lower chance of pCR in post-NAC rCR patients. The receptor subtype remained a reliable predictor of pCR. Residual mammographic calcifications correlated with higher odds of malignancy, making the correlation between mammography and MRI essential for surgical planning. Key Points • The presence of a multicentric lesion on pre-NAC MRI, even though the patient reaches a radiologic complete response on MRI, is associated with a lower chance of pCR. • Molecular status of the tumor remained the only significant predictor of pathologic complete response in such patients in the present study. • Post-neoadjuvant residual calcifications found on mammography were related to higher odds of residual malignancy, making the correlation between mammography and MRI essential for surgical planning.

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.

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.

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.