CT and MR Enterography in the Evaluation of Celiac Disease.

Celiac disease is a common inflammatory disease of the small bowel that induces mucosal intestinal lesions. The disease is mediated by an immune response and triggered by the ingestion of gluten in genetically predisposed individuals. Gluten contains gliadin, a component found mostly in wheat, barley, and rye. This process leads to gastrointestinal malabsorption with symptoms such as diarrhea, constipation, abdominal pain, and distention. It has a prevalence of 1%-2% in the general adult population, who present with symptoms at any age, but is more frequently found in adult women in the 3rd or 4th decade of life. Recognition of the disease has increased, but it remains a challenge to diagnose. CT and MR enterography are noninvasive studies used for evaluation of small bowel neoplasms and inflammatory small bowel pathologic conditions such as celiac disease. The authors review the spectrum of intestinal and extraintestinal findings of celiac disease at CT and MR enterography, as well as its complications, and the importance of recognizing certain imaging features that help in the diagnosis of celiac disease. More common and specific findings of celiac disease such as inversion of the jejunoileal fold pattern and mesenteric lymphadenopathy are reviewed. More uncommon entities that are more frequently associated with refractory or untreated celiac disease, such as ulcerative jejunoileitis, cavitary mesenteric lymph node syndrome, and malignancies including small bowel adenocarcinoma and lymphoma, are described. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. The slide presentation from the RSNA Annual Meeting is available for this article.

Chest x-ray automated triage: A semiologic approach designed for clinical implementation, exploiting different types of labels through a combination of four Deep Learning architectures.

BACKGROUND AND OBJECTIVES: The multiple chest x-ray datasets released in the last years have ground-truth labels intended for different computer vision tasks, suggesting that performance in automated chest x-ray interpretation might improve by using a method that can exploit diverse types of annotations. This work presents a Deep Learning method based on the late fusion of different convolutional architectures, that allows training with heterogeneous data with a simple implementation, and evaluates its performance on independent test data. We focused on obtaining a clinically useful tool that could be successfully integrated into a hospital workflow. MATERIALS AND METHODS: Based on expert opinion, we selected four target chest x-ray findings, namely lung opacities, fractures, pneumothorax and pleural effusion. For each finding we defined the most suitable type of ground-truth label, and built four training datasets combining images from public chest x-ray datasets and our institutional archive. We trained four different Deep Learning architectures and combined their outputs with a late fusion strategy, obtaining a unified tool. The performance was measured on two test datasets: an external openly-available dataset, and a retrospective institutional dataset, to estimate performance on the local population. RESULTS: The external and local test sets had 4376 and 1064 images, respectively, for which the model showed an area under the Receiver Operating Characteristics curve of 0.75 (95%CI: 0.74-0.76) and 0.87 (95%CI: 0.86-0.89) in the detection of abnormal chest x-rays. For the local population, a sensitivity of 86% (95%CI: 84-90), and a specificity of 88% (95%CI: 86-90) were obtained, with no significant differences between demographic subgroups. We present examples of heatmaps to show the accomplished level of interpretability, examining true and false positives. CONCLUSION: This study presents a new approach for exploiting heterogeneous labels from different chest x-ray datasets, by choosing Deep Learning architectures according to the radiological characteristics of each pathological finding. We estimated the tool's performance on the local population, obtaining results comparable to state-of-the-art metrics. We believe this approach is closer to the actual reading process of chest x-rays by professionals, and therefore more likely to be successful in a real clinical setting.

Prostatitis crónica: Aporte del contraste endovenoso en fase tardía para su caracterización en resonancia magnética multiparamétrica de próstata / Chronic Prostatitis: Contrast Contribution in Late Phase for its Characterization in Multiparametric-Magnetic Resonance Imaging of the Prostate

Resumen Objetivo: El objetivo de este estudio es demostrar la utilidad de una secuencia tardía post-contraste en la resonancia magnética multiparamétrica de próstata (RMMP) para caracterizar lesiones PI-RADS II. Materiales y métodos: Se analizaron en forma retrospectiva las RMMP realizadas entre enero de 2015 y diciembre de 2016. El protocolo de la RMMP fue basado en las recomendaciones del PI-RADS versión 2, y se agregó una adquisición tardía luego del dinámico post-contraste. Los reportes fueron revisados bajo la versión 2.1. Resultados: Se seleccionaron 31 pacientes que presentaron lesiones categorizadas como PI-RADS II en la zona periférica, los cuales se encontraban en seguimiento del antígeno prostático específico y presentaron confirmación histológica de prostatitis crónica. Se evidenció un realce tardío de la lesión en todos los pacientes. Según los resultados histopatológicos, 30 presentaban prostatitis crónica y el restante tejido benigno (tejido fibromuscular). Discusión: La prostatitis crónica no muestra realce temprano, y presenta realce tardío debido al tejido conectivo fibroso que la compone. En la RMMP, la prostatitis puede imitar el cáncer de próstata. Agregar una adquisición tardía solo adiciona 150 segundos al estudio y podría ayudar a resolver aquellos casos inciertos categorizados como PI-RADS III empleando las secuencias convencionales, debido a que el realce tardío de la lesión es altamente sugestivo de un proceso inflamatorio (PI-RADS II). Conclusión: La presencia de realce tardío es una herramienta útil para realizar un adecuado diagnóstico de una lesión PI-RADS II en la zona periférica, pudiendo evitar una biopsia innecesaria.

Abstract Objective: The aim of this study is to demonstrate the utility of a post-contrast late sequence in multiparametric magnetic resonance imaging (RMMP) to characterize PI-RADS II lesions. Materials and methods: The RMMPs performed between January 2015 and December 2016 were retrospectively analyzed. The RMMP protocol was based on the recommendations of the PI-RADS version 2, and a late acquisition was added, after the dynamic post-contrast. The reports were reviewed under the version 2.1. Results: 31 patients with PI-RADS II lesions in the peripheral zone were selected, who were in prostate specific antigen follow-up and had histological confirmation of chronic prostatitis. A late enhancement of the lesion was evidenced in all patients. According to the histopathological results, 30 had chronic prostatitis and the remaining benign tissue (fibromuscular tissue). Discussion: Chronic prostatitis does not show early enhancement, and presents late enhancement due to its fibrous connective tissue. In RMMP, prostatitis may mimic prostate cancer. Adding a late sequence only adds 150 seconds to the study and could help to resolve those uncertain cases categorized as PI-RADS III using traditional sequences because the late enhancement of the lesion is highly suggestive of an inflammatory process (PI-RADS II). Conclusion: The presence of late enhancement is a useful tool to perform an adequate diagnosis of a PI-RADS II lesion in the peripheral zone, helping to avoid an unnecessary biopsy.

Enterotomografía en la enfermedad de Crohn / CT enterography in Crohn's disease

Objetivos de aprendizaje. Definir el aporte de la enterotomografía (ETC) para el diagnóstico, control y pronóstico de la enfermedad de Crohn (EC) y detallar su forma de adquisición. Compararlo con otros métodos de diagnóstico utilizados para el estudio del intestino delgado y establecer sus ventajas y desventajas. Revisión del tema. La EC es una enfermedad inflamatoria intestinal crónica, que afecta a todo el tubo digestivo de forma discontinua y transmural. Son objetivos a determinar el compromiso del intestino delgado, el diagnóstico de la etapa aguda de la enfermedad y su respuesta al tratamiento. El curso de la enfermedad,sus complicaciones (sangrado, obstrucción, estrangulamiento, abscesos y fístulas) y la severidad de los síntomas presentan una evolución variable. El diagnóstico inicial se basa en la combinación de la clínica, los hallazgos endoscópicos, bioquímicos y radiológicos. Hallazgos en imágenes. Los hallazgos característicos de la enfermedad estudiada con ETC son: aumento del realce mural e imágenes ganglionares con realce luego del contraste E.V. (ambos signos de actividad), incremento del espesor parietal y signo del halo (anillo hipodenso por depósito graso en la submucosa), proliferación de la grasa mesentérica, prominencia de los vasos rectos, áreas de estenosis, fístulas y abscesos.Conclusión. La ETC es un método accesible y fácil de emplear. Permite determinar la extensión y fase de progresión de la enfermedad, el compromiso extraintestinal y las eventuales complicaciones. La combinación de un tiempo corto de examen, una única respiración sostenida, la accesibilidad y disponibilidad del método le otorgan un rol importante en el diagnóstico y seguimiento de estos pacientes...

Enterotomografía en la enfermedad de Crohn / CT enterography in Crohns disease

Resumen Objetivos de aprendizaje. Definir el aporte de la enterotomografía (ETC) para el diagnóstico, control y pronóstico de la enfermedad de Crohn (EC) y detallar su forma de adquisición. Compararlo con otros métodos de diagnóstico utilizados para el estudio del intestino delgado y establecer sus ventajas y desventajas. Revisión del tema. La EC es una enfermedad inflamatoria intestinal crónica, que afecta a todo el tubo digestivo de forma discontinua y transmural. Son objetivos a determinar el compromiso del intestino delgado, el diagnóstico de la etapa aguda de la enfermedad y su respuesta al tratamiento. El curso de la enfermedad, sus complicaciones (sangrado, obstrucción, estrangulamiento, abscesos y fístulas) y la severidad de los síntomas presentan una evolución variable. El diagnóstico inicial se basa en la combinación de la clínica, los hallazgos endoscópicos, bioquímicos y radiológicos. Hallazgos en imágenes. Los hallazgos característicos de la enfermedad estudiada con ETC son: aumento del realce mural e imágenes ganglionares con realce luego del contraste E.V. (ambos signos de actividad), incremento del espesor parietal y signo del halo (anillo hipodenso por depósito graso en la submucosa), proliferación de la grasa mesentérica, prominencia de los vasos rectos, áreas de estenosis, fístulas y abscesos. Conclusión. La ETC es un método accesible y fácil de emplear. Permite determinar la extensión y fase de progresión de la enfermedad, el compromiso extraintestinal y las eventuales complicaciones. La combinación de un tiempo corto de examen, una única respiración sostenida, la accesibilidad y disponibilidad del método le otorgan un rol importante en el diagnóstico y seguimiento de estos pacientes.(AU)

Learning Objectives. To define the contribution of CT enterography (CTE) to the diagnosis, follow-up and prognosis of Crohns disease, and to detail image acquisition. To compare CT enterography with other diagnostic methods used for the study of the small bowel, defining advantages and disadvantages. Topic Review. Crohns disease is a chronic inflammatory bowel disease that affects the entire gastrointestinal tract with a discontinuous and transmural compromise. The objectives are to determine small bowel involvement, diagnosis of active disease and its response to treatment. The course of disease, its complications (bleeding, obstruction, strangulation, abscesses and fistulas) and the severity of symptoms are variable. Initial diagnosis is based on a combination of clinical, endoscopic, biochemical and radiological findings. Image Findings. The characteristic features in CTE are increased mural enhancement and enhanced lymph nodes after the administration of IV contrast (both signs of activity), wall thickening and halo sign (low attenuation ring in bowel due to deposit of submucosal fat), proliferation of mesenteric fat, prominence of the vasa recta, areas of stenosis, fistulas and abscesses. Conclusion. CTE is readily available and easy to perform, being possible to determine the extent and stage of disease progression, extraintestinal involvement and potential complications. The combination of a short examination time, a single breath hold, accessibility and availability has made CTE an important tool in the diagnosis and follow-up of patients with Crohns disease.(AU)