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.

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.

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.

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.

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.

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.

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.

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.

Bosniak classification of cystic renal masses version 2019 does not increase the interobserver agreement or the proportion of masses categorized into lower Bosniak classes for non-subspecialized readers on CT or MR.

PURPOSE: In a condition so prevalent as renal cysts, classifications should display satisfactory reproducibility not only among subspecialized readers. We aimed to compare the interobserver agreement of the Bosniak classification version 2019 (BC19) and current Bosniak classification (CBC) for non-subspecialized readers on CT and MRI and to verify whether BC19 leads to a downgrade of renal cystic masses when compared to CBC. METHODS: We evaluated 50 renal cystic masses in 47 patients on MR and CT (25 per method). Eighteen readers (nine third-year radiology residents and nine abdominal imaging fellows) assessed the images using BC19 and CBC with an eight-week interval. Kappa statistic was used to assess agreement. An average score of Bosniak categories across all raters evaluated if there was downgrading of lesions on BC19. RESULTS: The highest values of Kappa were found for fellows on CBC-MR (κ = 0.51), and the lowest values were found for residents on CBC-MR and fellows on BC19-MR (both κ = 0.36). On CBC, interobserver agreement was moderate for MR and CT (κ = 0.42 and 0.43, respectively), whereas on BC19, it was fair (κ = 0.38 and 0.40, respectively). The best agreements were in categories I (κ = 0.49-0.69) and IV (κ = 0.45-0.51). The poorest agreements occurred at IIF (κ = 0.18 on BC19-CT). There was a moderate median increase from CBC to BC19 in terms of Bosniak categories for both methods (MR [Z=-2.058, p = 0.040] and CT [Z=-2.509, p = 0.012]). CONCLUSION: BC19, when compared to CBC, did not improve interobserver agreement nor diminished the proportion of masses categorized into lower Bosniak classes among non-subspecialized readers.

Non-neoplastic cholangiopathies: an algorithmic approach.

Cholangiopathies are chronic diseases that affect the bile ducts, comprising a heterogeneous group of progressive and potentially fatal entities. The diagnosis of these diseases is a great challenge for radiologists because of the overlapping of their clinical, biochemical, and imaging findings. Nevertheless, identifying the precise etiology is crucial, given that the therapeutic options are distinct and influence the prognosis of the patient. The purpose of this review article is to discuss some of the non-neoplastic causes of cholangiopathies and to provide a useful diagnostic algorithm.

As colangiopatias são doenças crônicas que afetam as vias biliares, constituindo um grupo heterogêneo de doenças progressivas e potencialmente fatais. O seu diagnóstico configura um grande desafio para os radiologistas, uma vez que seus aspectos clínicos, laboratoriais e de imagem se sobrepõem. Apesar disso, a busca etiológica é crucial, tendo em vista que as opções terapêuticas são distintas e influenciam o prognóstico do paciente. O objetivo deste artigo de revisão é discutir algumas das causas não neoplásicas de colangiopatias e fornecer um algoritmo útil na abordagem diagnóstica.

Hepatic neuroendocrine neoplasm: imaging patterns.

Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors with distinct morphological and biological manifestations, the liver being the main organ affected by its metastases. However, primary hepatic involvement is quite rare. Hepatic NENs can have a variety of radiological presentation forms and can therefore mimic other lesions, making their diagnosis challenging. Nonetheless, certain imaging aspects allow NENs to be included among the main differential diagnoses of hepatic lesions and can guide the search for an extrahepatic primary site when the probable diagnosis is metastases.

As neoplasias neuroendócrinas (NNEs) são um grupo heterogêneo de tumores com manifestações morfológicas e biológicas distintas, sendo o fígado o principal órgão acometido por suas metástases. Por outro lado, o acometimento primário deste órgão é muito raro. Podem-se observar as mais diversas formas de apresentação radiológica das NNEs hepáticas primária e secundária e, em razão dessa variedade e por mimetizar outras lesões, o seu diagnóstico pode se revelar um desafio. No entanto, alguns desses aspectos permitem incluir as NNEs entre os principais diagnósticos diferenciais de lesões hepáticas e, nos casos de metástases, orientar na busca de um eventual sítio primário extra-hepático.

Estimating the productivity of radiologists in Brazil: the search for a benchmark / Estimativa da produtividade de radiologistas brasileiros: a busca por um padrão de referência

Abstract Objective: To determine the average productivity of radiologists, as measured by number of reports issued per 6-h shift, evaluating variables that could affect the results. Materials and Methods: This was a study utilizing an online questionnaire sent to radiologists affiliated with the Brazilian College of Radiology and Diagnostic Imaging. The questions were related to the demographic profile and professional practice characteristics (form of remuneration, primary imaging method employed, and subspecialty) of the radiologists, as well as their individual productivity (average personal productivity) and the productivity considered reasonable in a 6-h shift. The association between productivity and the practice characteristics of the radiologists was determined by using Poisson regression to calculate the prevalence ratio. Results: A total of 510 radiologists completed the questionnaire. The great majority of the respondents (84%) reported that their remuneration is directly related to their productivity. The productivity varied according to the subspecialty, work environment, and remuneration model. Conclusion: We demonstrated that the productivity of radiologists is associated with the characteristics of their employment. We hope that this study will encourage other studies aimed at evaluating the productive capacity of the radiologists in Brazil, addressing the various functions they perform in their daily routine, including activities other than issuing reports.

Resumo Objetivo: Estimar a produtividade média dos radiologistas brasileiros em número de laudos emitidos por período de trabalho de seis horas, analisando variáveis que possam influenciar os resultados. Materiais e Métodos: Pesquisa realizada por meio de questionários online respondidos por radiologistas brasileiros afiliados ao Colégio Brasileiro de Radiologia e Diagnóstico por Imagem. As questões incluíram dados demográficos e profissionais dos radiologistas (forma de remuneração, método de imagem de atuação e subespecialidade) e a produtividade individual e a considerada razoável em um período de seis horas de trabalho. A associação entre a produtividade e as características de trabalho dos radiologistas foi calculada pela razão de prevalência, por meio da regressão de Poisson. Resultados: Ao todo, 510 radiologistas responderam ao questionário. A grande maioria dos respondedores (84%) relatou que a sua remuneração está diretamente relacionada à produtividade. A produtividade variou em função da subespecialidade de atuação, ambiente de trabalho e modelo de remuneração. Conclusão: Demonstramos a associação entre a produtividade do radiologista e as características relacionadas à forma de trabalho. Esperamos que este estudo impulsione outras pesquisas que avaliem a capacidade produtiva do radiologista brasileiro, considerando as diversas funções exercidas por este profissional em sua rotina de trabalho, contemplando outras atividades, além da emissão de laudos.

Evaluating inflammatory activity in Crohn's disease by cross-sectional imaging techniques / Avaliação da atividade inflamatória da doença de Crohn por métodos seccionais de imagem

Abstract The evaluation of inflammatory bowel activity in patients with Crohn's disease has traditionally been a challenge, mainly because of the difficulty in gaining endoscopic access to the small bowel. Historically, barium-based contrast studies were the only option for the evaluation of inflammatory activity in Crohn's disease. They were gradually replaced by cross-sectional imaging techniques, computed tomography enterography (CTE) and magnetic resonance enterography (MRE) now being the modalities of choice for such evaluations. Those two imaging methods have provided important information regarding intestinal wall involvement and extra-intestinal manifestations of Crohn's disease, not only assessing lesion characteristics and complications but also quantifying inflammatory bowel activity. The objective of this article is to review the main technical aspects of CTE and MRE, together with their indications, contraindications, and limitations, as well as the CTE and MRE imaging characteristics of inflammatory activity in Crohn's disease.

Resumo A avaliação da atividade inflamatória intestinal em pacientes com doença de Crohn tem sido tradicionalmente um desafio, principalmente pela dificuldade do acesso endoscópico ao intestino delgado. Por muito tempo os estudos baritados foram a única opção disponível, tendo sido progressivamente substituídos por novas técnicas de imagens seccionais, sendo hoje a enterografia por tomografia computadorizada (entero-TC) e por ressonância magnética (entero-RM) as modalidades de escolha para essa avaliação. Esses dois métodos de imagem acrescentam informações importantes quanto ao acometimento da parede intestinal e às manifestações extraintestinais relacionadas à doença de Crohn, avaliando não somente as características das lesões e as complicações, mas também quantificando a atividade inflamatória intestinal. O objetivo deste artigo é revisar os principais aspectos técnicos dos exames, as suas indicações, contraindicações, limitações e características de imagem da entero-TC e entero-RM na avaliação da atividade inflamatória da doença de Crohn.