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.

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 and magnetic resonance imaging, 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.

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.

Advanced MR imaging for detection of liver fibrosis and inflammation in autoimmune hepatitis: a state-of-the-art review.

Autoimmune hepatitis (AIH) 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 AIH in terms of liver inflammation and fibrosis, developing the virtual biopsy concept. Therefore, we review the state-of-the-art of Magnetic Resonance Imaging (MRI) sequences for the noninvasive evaluation of autoimmune hepatitis, including historical advances and future directions.

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.

Tips and tricks for a proper radiological assessment of abdominal and pelvic lymph nodes.

The assessment of lymph node dimensions is a commonly used criterion in analyzing lymphatic involvement related to inflammatory or neoplastic diseases. However, it is important to understand that the interpretation of lymph nodes goes beyond simply considering their size. A pathologic lymph node can present with enlarged dimensions, a heterogeneous appearance, increased cortex thickness, irregular contours, or a lobulated shape. In this context, it is essential to consider not only the dimensions but also the morphology, attenuation, and enhancement of lymph nodes on imaging exams. This article aims to demonstrate how characteristics of lymph nodes, beyond their size, can provide crucial insights that assist in diagnostic reasoning, focusing on computed tomography. By emphasizing different enhancement patterns, attenuation, and the potential contents related to these patterns, the study seeks to show how these features can indicate possible differential diagnoses and guide more accurate clinical assessments.

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.

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.