Preoperative evaluation of prostate cancer by 68Ga-PMSA positron emission tomography/computed tomography: comparison with magnetic resonance imaging and with histopathological findings.

Objective: To evaluate the accuracy of preoperative positron emission tomography/computed tomography with 68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA PET/CT) for staging prostate cancer and compare it with magnetic resonance imaging (MRI) using histopathology of surgical specimens as the gold standard. Materials and Methods: In this retrospective study, 65 patients with prostate cancer were analyzed. Results: The accuracy of 68Ga-PSMA PET/CT for tumor detection was 95%, and that of MRI was 91%. There was no difference between 68Ga-PSMA PET/CT and MRI regarding localization of the lesion. The sensitivity of 68Ga-PSMA PET/CT for detecting extraprostatic extension was quite low (14%). For detection of seminal vesicle invasion, 68Ga-PSMA PET/CT showed a sensitivity of 57% and accuracy of 91%. There was a moderate correlation between the maximum standardized uptake value (SUVmax) and the serum level of prostate-specific antigen (p < 0.01; ρ = 0.368) and between the SUVmax and the International Society of Urological Pathology (ISUP) grade (p < 0.01; ρ = 0.513). Conclusion: 68Ga-PSMA PET/CT is a promising tool for detecting and evaluating the primary tumor, which can alter the staging and management of the disease.

Objetivo: Avaliar a acurácia da tomografia por emissão de pósitrons/tomografia computadorizada com PSMA (PET-PMSA) pré-operatória para estadiamento do câncer de próstata e compará-la com a ressonância magnética (RM) utilizando o histopatológico cirúrgico como padrão ouro. Materiais e Métodos: Neste estudo retrospectivo foram analisados 65 pacientes com câncer de próstata. Resultados: A acurácia da PET-PSMA para a detecção tumoral foi de 95% e a da RM foi de 91%. Não houve diferença entre a PET-PSMA e a RM quanto à localização da lesão. A PET-PSMA apresentou baixa sensibilidade (14%) para detecção de extensão extraprostática em comparação ao histopatológico. Para detecção de invasão de vesícula seminal, a PET-PSMA apresentou sensibilidade de 57% e acurácia de 91% em comparação ao histopatológico. Houve correlação moderada entre o SUVmax e o PSA (p < 0,01; ρ = 0,368) e entre o SUVmax e o ISUP (p < 0,01; ρ = 0,513). Conclusão: A PET-PSMA é uma ferramenta promissora para detecção e avaliação do tumor primário, alterando o estadiamento e a conduta do paciente.

Crohn's disease: review and standardization of nomenclature / Doença de Crohn: revisão e padronização da nomenclatura

Abstract Crohn's disease is an inflammatory bowel disease that can affect any segment of the gastrointestinal tract. It has a variable clinical course, with alternating periods of disease activity and remission. Because the incidence and prevalence of Crohn's disease have been increasing, evaluation by imaging methods has become more important. The most widely used methods are computed tomography enterography, magnetic resonance enterography (as an elective examination), and contrast-enhanced computed tomography (in the context of emergency). Computed tomography enterography and magnetic resonance enterography are useful for diagnosis, follow-up, evaluation of complications, and prognosis. Both can be used in order to evaluate the small bowel loops and the associated mesenteric findings, as well as to evaluate other abdominal organs. They both also can detect signs of disease activity, fibrosis, penetrating disease, and complications. The interpretation of such changes is essential to the multidisciplinary approach, as is the standardization of the nomenclature employed in the reports. In this paper, we review and illustrate the imaging findings of Crohn's disease, using the standardized nomenclature proposed in the multidisciplinary consensus statement issued by the Society of Abdominal Radiology, the Society of Pediatric Radiology, and the American Gastroenterology Association, with recommendations for descriptions, interpretations, and impressions related to those findings.

Resumo Doença de Crohn é uma doença inflamatória intestinal que pode acometer qualquer segmento do trato gastrointestinal, com curso clínico variado, alternando períodos de atividade de doença e remissão. Sua incidência e prevalência vêm aumentando, tornando a avaliação por métodos de imagem mais importante. Os métodos mais utilizados são enterotomografia computadorizada, enterorressonância magnética eletivamente e tomografia computadorizada com contraste no contexto da emergência. A enterotomografia computadorizada e a enterorressonância magnética são úteis para diagnóstico, seguimento, avaliação de complicações e para prognóstico. Avaliam as alças intestinais delgadas e os achados mesentéricos associados, além dos demais órgãos abdominais. Detectam sinais de atividade de doença, sinais de cronicidade e doença penetrante e complicações, importantes para a escolha do melhor tratamento. A interpretação dessas alterações é fundamental para que a equipe multidisciplinar trabalhe conjuntamente com compreensão da linguagem utilizada nos relatórios. Neste artigo, apresentamos uma revisão dos achados de imagem da doença de Crohn e ilustramos os possíveis achados dessa doença utilizando a nomenclatura padronizada proposta no consenso multidisciplinar composto pelas Sociedade de Radiologia Abdominal, Sociedade de Radiologia Pediátrica e a Associação Americana de Gastroenterologia, com recomendações de descrição, interpretação dos achados e recomendações de impressão.

Artificial intelligence to predict the need for mechanical ventilation in cases of severe COVID-19 / Inteligência artificial na predição de necessidade de ventilação mecânica em casos graves de COVID-19

Abstract Objective: To determinate the accuracy of computed tomography (CT) imaging assessed by deep neural networks for predicting the need for mechanical ventilation (MV) in patients hospitalized with severe acute respiratory syndrome due to coronavirus disease 2019 (COVID-19). Materials and Methods: This was a retrospective cohort study carried out at two hospitals in Brazil. We included CT scans from patients who were hospitalized due to severe acute respiratory syndrome and had COVID-19 confirmed by reverse transcriptionpolymerase chain reaction (RT-PCR). The training set consisted of chest CT examinations from 823 patients with COVID-19, of whom 93 required MV during hospitalization. We developed an artificial intelligence (AI) model based on convolutional neural networks. The performance of the AI model was evaluated by calculating its accuracy, sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve. Results: For predicting the need for MV, the AI model had a sensitivity of 0.417 and a specificity of 0.860. The corresponding area under the ROC curve for the test set was 0.68. Conclusion: The high specificity of our AI model makes it able to reliably predict which patients will and will not need invasive ventilation. That makes this approach ideal for identifying high-risk patients and predicting the minimum number of ventilators and critical care beds that will be required.

Resumo Objetivo: Determinar a acurácia da tomografia computadorizada (TC), avaliada por redes neurais profundas, na ventilação mecânica, de pacientes hospitalizados por síndrome respiratória aguda grave por COVID-19. Materiais e Métodos: Trata-se de estudo de coorte retrospectivo, realizado em dois hospitais brasileiros. Foram incluídas TCs de pacientes hospitalizados por síndrome respiratória aguda grave e COVID-19 confirmada por RT-PCR. O treinamento consistiu em TC de tórax de 823 pacientes com COVID-19, dos quais 93 foram submetidos a ventilação mecânica na hospitalização. Nós desenvolvemos um modelo de inteligência artificial baseado em redes de convoluções neurais. A avaliação do desempenho do uso da inteligência artificial foi baseada no cálculo de acurácia, sensibilidade, especificidade e área sob a curva ROC. Resultados: A sensibilidade do modelo foi de 0,417 e a especificidade foi de 0,860. A área sob a curva ROC para o conjunto de teste foi de 0,68. Conclusão: Criamos um modelo de aprendizado de máquina com elevada especificidade, capaz de prever de forma confiável pacientes que não precisarão de ventilação mecânica. Isso significa que essa abordagem é ideal para prever com antecedência pacientes de alto risco e um número mínimo de equipamentos de ventilação e de leitos críticos.

Preoperative evaluation of prostate cancer by 68Ga-PMSA positron emission tomography/computed tomography: comparison with magnetic resonance imaging and with histopathological findings / Avaliação pré-operatória do câncer de próstata pela tomografia por emissão de pósitrons/tomografia computadorizada com PSMA-68Ga: comparação com ressonância magnética e com achados histopatológicos

Abstract Objective: To evaluate the accuracy of preoperative positron emission tomography/computed tomography with 68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA PET/CT) for staging prostate cancer and compare it with magnetic resonance imaging (MRI) using histopathology of surgical specimens as the gold standard. Materials and Methods: In this retrospective study, 65 patients with prostate cancer were analyzed. Results: The accuracy of 68Ga-PSMA PET/CT for tumor detection was 95%, and that of MRI was 91%. There was no difference between 68Ga-PSMA PET/CT and MRI regarding localization of the lesion. The sensitivity of 68Ga-PSMA PET/CT for detecting extraprostatic extension was quite low (14%). For detection of seminal vesicle invasion, 68Ga-PSMA PET/CT showed a sensitivity of 57% and accuracy of 91%. There was a moderate correlation between the maximum standardized uptake value (SUVmax) and the serum level of prostate-specific antigen (p < 0.01; ρ = 0.368) and between the SUVmax and the International Society of Urological Pathology (ISUP) grade (p < 0.01; ρ = 0.513). Conclusion: 68Ga-PSMA PET/CT is a promising tool for detecting and evaluating the primary tumor, which can alter the staging and management of the disease.

Resumo Objetivo: Avaliar a acurácia da tomografia por emissão de pósitrons/tomografia computadorizada com PSMA (PET-PMSA) pré-operatória para estadiamento do câncer de próstata e compará-la com a ressonância magnética (RM) utilizando o histopatológico cirúrgico como padrão ouro. Materiais e Métodos: Neste estudo retrospectivo foram analisados 65 pacientes com câncer de próstata. Resultados: A acurácia da PET-PSMA para a detecção tumoral foi de 95% e a da RM foi de 91%. Não houve diferença entre a PET-PSMA e a RM quanto à localização da lesão. A PET-PSMA apresentou baixa sensibilidade (14%) para detecção de extensão extraprostática em comparação ao histopatológico. Para detecção de invasão de vesícula seminal, a PET-PSMA apresentou sensibilidade de 57% e acurácia de 91% em comparação ao histopatológico. Houve correlação moderada entre o SUVmax e o PSA (p < 0,01; ρ = 0,368) e entre o SUVmax e o ISUP (p < 0,01; ρ = 0,513). Conclusão: A PET-PSMA é uma ferramenta promissora para detecção e avaliação do tumor primário, alterando o estadiamento e a conduta do paciente.

Neurofibromatosis type 1: evaluation by chest computed tomography.

OBJECTIVE: The aim of this study was to evaluate chest computed tomography (CT) findings in patients diagnosed with neurofibromatosis type 1 (NF1). MATERIAL AND METHODS: This was a retrospective study in which we reviewed the chest CT scans of 14 patients diagnosed with NF1 and neurofibromatosis-associated diffuse lung disease (NF-DLD). The sample comprised eight women and six men. The median age was 55 years (range, 11-75 years). The diagnosis of NF1 was made on the basis of the diagnostic criteria established by the U.S. National Institutes of Health. The images were analyzed by two chest radiologists, who reached decisions by consensus. RESULTS: The predominant CT finding of NF-DLD was multiple cysts, which were observed in 13 patients (92.9%), followed by emphysema, in eight (57.1%) and subpleural bullae, in six (42.9%). Other findings included subcutaneous neurofibromas, in 12 patients (85.7%), ground-glass opacities, in one (7.1%), and tracheobronchial neurofibromas, in one (7.1%). The pulmonary abnormalities were bilateral in 12 cases (85.7%). The abnormalities were predominantly in the upper lung fields in eight cases (57.1%), and their distribution was random in 11 (78.6%). CONCLUSION: Pulmonary cysts, emphysema, and subpleural bullae appear to be the chest CT findings that are most characteristic of NF-DLD.

OBJETIVO: O objetivo deste estudo foi avaliar os achados pulmonares na tomografia computadorizada do tórax de pacientes diagnosticados com neurofibromatose tipo 1 (NF1). MATERIAIS E MÉTODOS: Foram revisados, retrospectivamente, os achados tomográficos de 14 pacientes com doença pulmonar difusa associada à NF1 (NF-DPD). A amostra incluiu oito mulheres e seis homens, com idade entre 11 e 75 anos (mediana de idade de 55 anos). O diagnóstico foi estabelecido com base em critérios diagnósticos predeterminados pelo National Institutes of Health dos Estados Unidos. As imagens foram analisadas de forma independente por dois radiologistas, que chegaram a um consenso. RESULTADOS: Os achados tomográficos predominantes foram múltiplos cistos em 13 pacientes (92,9%), enfisema em oito (57,1%) e bolhas subpleurais em seis (42,9%). Achados associados incluíram neurofibromas cutâneos e subcutâneos em 12 pacientes (85,7%), opacidades em vidro fosco em um (7,1%) e neurofibromas traqueobrônquicos em um (7,1%). As anormalidades pulmonares foram bilaterais em 12 casos (85,7%). Houve predomínio nos terços superiores em oito (57,1%) pacientes e se distribuíram randomicamente pelos pulmões em 11 (78,6%). CONCLUSÃO: Os achados tomográficos pulmonares mais frequentes na NF-DPD foram os cistos pulmonares, o enfisema e as bolhas subpleurais.

Neurofibromatosis type 1: evaluation by chest computed tomography / Neurofibromatose tipo 1: estudo por tomografia computadorizada do tórax

Abstract Objective: The aim of this study was to evaluate chest computed tomography (CT) findings in patients diagnosed with neurofibromatosis type 1 (NF1). Material and Methods: This was a retrospective study in which we reviewed the chest CT scans of 14 patients diagnosed with NF1 and neurofibromatosis-associated diffuse lung disease (NF-DLD). The sample comprised eight women and six men. The median age was 55 years (range, 11-75 years). The diagnosis of NF1 was made on the basis of the diagnostic criteria established by the U.S. National Institutes of Health. The images were analyzed by two chest radiologists, who reached decisions by consensus. Results: The predominant CT finding of NF-DLD was multiple cysts, which were observed in 13 patients (92.9%), followed by emphysema, in eight (57.1%) and subpleural bullae, in six (42.9%). Other findings included subcutaneous neurofibromas, in 12 patients (85.7%), ground-glass opacities, in one (7.1%), and tracheobronchial neurofibromas, in one (7.1%). The pulmonary abnormalities were bilateral in 12 cases (85.7%). The abnormalities were predominantly in the upper lung fields in eight cases (57.1%), and their distribution was random in 11 (78.6%). Conclusion: Pulmonary cysts, emphysema, and subpleural bullae appear to be the chest CT findings that are most characteristic of NF-DLD.

Resumo Objetivo: O objetivo deste estudo foi avaliar os achados pulmonares na tomografia computadorizada do tórax de pacientes diagnosticados com neurofibromatose tipo 1 (NF1). Materiais e Métodos Foram revisados, retrospectivamente, os achados tomográficos de 14 pacientes com doença pulmonar difusa associada à NF1 (NF-DPD). A amostra incluiu oito mulheres e seis homens, com idade entre 11 e 75 anos (mediana de idade de 55 anos). O diagnóstico foi estabelecido com base em critérios diagnósticos predeterminados pelo National Institutes of Health dos Estados Unidos. As imagens foram analisadas de forma independente por dois radiologistas, que chegaram a um consenso. Resultados: Os achados tomográficos predominantes foram múltiplos cistos em 13 pacientes (92,9%), enfisema em oito (57,1%) e bolhas subpleurais em seis (42,9%). Achados associados incluíram neurofibromas cutâneos e subcutâneos em 12 pacientes (85,7%), opacidades em vidro fosco em um (7,1%) e neurofibromas traqueobrônquicos em um (7,1%). As anormalidades pulmonares foram bilaterais em 12 casos (85,7%). Houve predomínio nos terços superiores em oito (57,1%) pacientes e se distribuíram randomicamente pelos pulmões em 11 (78,6%). Conclusão: Os achados tomográficos pulmonares mais frequentes na NF-DPD foram os cistos pulmonares, o enfisema e as bolhas subpleurais.

Tomographic findings in bronchial atresia / Achados tomográficos na atresia brônquica

Abstract Objective: To evaluate computed tomography (CT) findings in 23 patients with bronchial atresia. Materials and Methods: The CT images were reviewed by two radiologists who reached decisions by consensus. We included only patients who presented with abnormalities on CT and in whom the diagnosis had been confirmed by pathological examination of the surgical specimen (if the lesion was resected). The CT scans were assessed in order to identify the main findings and to map the distribution of the lesions (i.e., to determine whether the pulmonary involvement was unilateral or bilateral). Results: The main CT finding was the combination of bronchocele and hyperinflation of the distal lung. That combination was observed in all of the patients. The lesions were unilateral in all 23 cases, being seen predominantly in the left upper lobe, followed by the right lower lobe, right upper lobe, middle lobe, and left lower lobe. Conclusion: The diagnosis of bronchial atresia can be reliably made on the basis of a finding of bronchocele accompanied by hyperinflation of the adjacent lung parenchyma.

Resumo Objetivo: Analisar os achados na tomografia computadorizada (TC) de tórax de 23 pacientes com atresia brônquica. Materiais e Métodos: As imagens de TC foram avaliadas por dois observadores e os casos discordantes foram resolvidos por consenso. Os critérios de inclusão foram a presença de anormalidades na TC compatíveis com atresia brônquica e/ou diagnóstico confirmado por exame anatomopatológico das peças cirúrgicas para os pacientes submetidos a ressecção cirúrgica. As TCs foram avaliadas quanto aos principais achados de imagem, à distribuição das lesões, ao envolvimento pulmonar unilateral ou bilateral. Resultados: Os principais achados na TC foram a presença de broncocele, hiperinsuflação do parênquima pulmonar ou ambos. A combinação desses achados foi encontrada em todos os pacientes. Em relação à distribuição, o envolvimento foi unilateral nos 23 casos. Quando se consideraram os lobos mais acometidos, o lobo superior esquerdo foi o mais acometido, seguido do lobo inferior direito, lobo superior direito, lobo médio e lobo inferior esquerdo. Conclusão: O diagnóstico de atresia brônquica pode ser feito em presença de broncocele associada com hiperinsuflação do parênquima pulmonar adjacente.

Can gadoxetic acid-enhanced magnetic resonance imaging be used to avoid liver biopsy in patients with nonalcoholic fatty liver disease?

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver disease worldwide. The diagnosis of nonalcoholic steatohepatitis (NASH), the most severe form of NAFLD, is crucial and has prognostic and therapeutic implications. However, currently this diagnosis is based on liver biopsy and has several limitations. AIM: To evaluate the performance of gadoxetic acid-enhanced magnetic resonance imaging (GA-MRI) in differentiating isolated steatosis from NASH in patients with NAFLD. METHODS: In this prospective study, 56 patients with NAFLD (18 with isolated steatosis and 38 with NASH) underwent GA-MRI. The contrast enhancement index (CEI) was calculated as the rate of increase of the liver-to-muscle signal intensity ratio from before and 20 min after intravenous GA administration. Between-group differences in mean CEI were examined using Student's t test. The area under the receiver operator characteristic curve and the diagnostic performance of gadoxetic acid-enhanced magnetic resonance imaging were evaluated. RESULTS: The mean CEI for all subjects was 1.82 ± 0.19. The mean CEI was significantly lower in patients with NASH than in those with isolated steatosis (P = 0.008). Two CEI cut-off points were used: < 1.66 (94% specificity) to characterize NASH and > 2.00 (89% sensitivity) to characterize isolated steatosis. CEI values between 1.66 and 2.00 indicated liver biopsy, and the procedure could be avoided in 40% of patients with NAFLD. CONCLUSION: GA-MRI is an effective noninvasive method that may be useful for the differentiation of NASH from isolated steatosis, and could help to avoid liver biopsy in patients with NAFLD.

Higher cut-off values of non-invasive methods might be needed to detect moderate-to-severe steatosis in morbid obese patients: a pilot study.

To evaluate the diagnostic value of described thresholds of controlled attenuation parameter (CAP) and biomarker scores for liver steatosis and to evaluate new cut-offs to detect moderate-to-severe steatosis (S2-3) in patients with morbid obesity. In this prospective study, 32 patients with morbid obesity with indications for bariatric surgery (15 women and 17 men, mean age = 36 years, median BMI = 40.2 kg/m2) underwent CAP, magnetic resonance spectroscopy (MRS), three biomarker scores (Steato-ELSA, Fatty Liver Index (FLI), and Hepatic Steatosis Index (HSI)), and liver biopsy. Subjects were divided into an exploratory cohort (reliable CAP and liver biopsy) and a confirmatory cohort (reliable CAP and MRS) to evaluate new thresholds for CAP and biomarker scores to detect S2-3. Receiver operator characteristic (ROC) curves analyses were performed and the optimal cut-off points were identified using the maximal Youden index. A total of 22 patients had CAP measure and liver biopsy (exploratory cohort) and 24 patients had CAP measure with MRS (confirmatory cohort). New cut-offs were identified for detection of S2-3 by the non-invasive tests using liver biopsy as the reference standard (exploratory cohort). Considering the new proposed cut-offs for detection of S2-3 for CAP (≥ 314 dB/m), Steato-ELSA (≥ 0.832), FLI (≥ 96), and HSI (≥ 53), for the exploratory and confirmatory cohorts sensitivities were: 71-75%, 86-81%, 85-81%, and 71-69% and specificities were: 94-89%, 75-63%, 63-63%, and 75-88%, respectively. Higher cut-offs for CAP and biomarker scores may be better to diagnose moderate-to-severe steatosis in patients with morbid obesity.

Computed tomography findings in a Brazilian cohort of 48 patients with pneumonia due to coronavirus disease.

INTRODUCTION: This study was conducted to retrospectively review chest computed tomography (CT) findings in a Brazilian cohort of patients with pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: Chest CT scans of 78 patients with confirmed coronavirus disease (COVID-19), obtained in March and April 2020, were reviewed. Of 78 cases, the CT scans of 48 (61.5%) showed lung opacities. CT opacity features, their distribution, and the extent of infiltration were evaluated. RESULTS: The most common CT findings were ground-glass opacities (97.9%), crazy-paving pattern (58.3%), and mixed pattern (18.8%). Rounded lung opacities were observed most frequently (70.8%). Other findings were cystic airspace changes (37.5%), vascular dilatation (35.4%), and the organizing pneumonia pattern (14.6%). The findings were frequently bilateral (87.5%), symmetrical (68.9%), and peripheral (60.2%). CONCLUSIONS: The most common CT findings were ground-glass opacities and the crazy-paving pattern. Involvement was mostly bilateral, symmetrical, and peripheral. Round opacity morphology was frequently observed and might have some degree of specificity to viral COVID-19 pneumonia.

Computed tomography findings in a Brazilian cohort of 48 patients with pneumonia due to coronavirus disease

Abstract INTRODUCTION: This study was conducted to retrospectively review chest computed tomography (CT) findings in a Brazilian cohort of patients with pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: Chest CT scans of 78 patients with confirmed coronavirus disease (COVID-19), obtained in March and April 2020, were reviewed. Of 78 cases, the CT scans of 48 (61.5%) showed lung opacities. CT opacity features, their distribution, and the extent of infiltration were evaluated. RESULTS: The most common CT findings were ground-glass opacities (97.9%), crazy-paving pattern (58.3%), and mixed pattern (18.8%). Rounded lung opacities were observed most frequently (70.8%). Other findings were cystic airspace changes (37.5%), vascular dilatation (35.4%), and the organizing pneumonia pattern (14.6%). The findings were frequently bilateral (87.5%), symmetrical (68.9%), and peripheral (60.2%). CONCLUSIONS: The most common CT findings were ground-glass opacities and the crazy-paving pattern. Involvement was mostly bilateral, symmetrical, and peripheral. Round opacity morphology was frequently observed and might have some degree of specificity to viral COVID-19 pneumonia.