A choking patient was admitted with dyspnea, cyanosis, and loss of consciousness, which initially improved after suction of the airways. The patient presented worsening of the clinical parameters until the introduction of supportive treatment, after which she rapidly recovered. Chest x-ray taken on day of hospitalization showed bilateral diffuse alveolar filling pattern, and computed tomography showed ground glass areas. The aim of this paper is to show the radiological features of this syndrome.

Keywords: Mendelson syndrome, Chest x-ray, Computed tomography

Our aim is to review the most common pathologic processes involving the iliopsoas compartment. We retrospectively reviewed the computed tomography (CT) scans performed at the "Departamento de Radiologia da Faculdade de Ciências Médicas da Universidade Estadual de Campinas", in the last 10 years, of patients who presented with abnormalities of the iliopsoas compartment that were confirmed by surgical or percutaneous biopsy. The most common findings involving the iliopsoas compartment included neoplasms, abscesses and hematomas. CT findings were based on the extension of the involvement of the psoas muscle, focal areas of low or high attenuation, lesion margins, presence of gas or calcification within the lesion, bone destruction, infiltration of surrounding fat and involvement of adjacent abdominal structures. CT is the method of choice for the detection of iliopsoas disorders, and its findings can be used to guide diagnostic aspiration, biopsy or drainage, when appropriate. However, the efficacy of CT in differentiating iliopsoas disorders is low when scans are interpreted without knowledge of clinical history.

Keywords: Iliopsoas muscle. Iliopsoas muscle ¾ computed tomography. Iliopsoas muscle ¾ pathology.

Objetivo: A principal utilidade da tomografia por emissão de pósitrons com 18-fluordeoxiglicose (FDG-PET) está no estadiamento do câncer de pulmão. Porém, ela também pode ser utilizada para diferenciar lesões pulmonares indeterminadas, mas seu impacto na ressecção cirúrgica de lesões benignas é desconhecido. O objetivo deste estudo foi comparar a prevalência de lesões benignas em toracotomias feitas por suspeição de câncer de pulmão, antes e após a introdução do FDG-PET, em um centro de referência de cirurgia torácica. Materiais e Métodos: Os autores analisaram, prospectivamente, uma base de dados cirúrgicos de todos os pacientes consecutivos submetidos a toracotomia por câncer de pulmão suspeito ou comprovado e compararam a prevalência de lesões benignas em dois grupos ao longo de dois anos consecutivos, respectivamente antes (grupo I) e depois (grupo II) da introdução da FDG-PET. Resultados: Ressecção cirúrgica foi feita em 1.233 pacientes durante o período do estudo. A prevalência de lesões benignas na cirurgia nos grupos I e II foi similar (44/626 e 41/607, ambas correspondendo a 7%), e também no grupo II, entre aqueles submetidos a FDG-PET e os restantes (21/301 e 20/306 respectivamente, ambos correspondendo a 7%). No grupo II, dos 21 pacientes com lesões benignas submetidos a FDG-PET, 19 tiveram um estudo falso-positivo (valor médio padrão de captação 5.3 [faixa 2.6–12.7]). Desses, respectivamente 13 e 4 pacientes tiveram broncoscopia não diagnóstica e biópsia transtorácica percutânea de pulmão antes da toracotomia. Não houve diferença na proporção de lesões benignas diferentes ressecadas entre o grupo I e aqueles submetidos a FDG-PET no grupo II. Conclusão: A introdução da FDG-PET não alterou a proporção de pacientes submetidos a toracotomia por lesões benignas, principalmente devido à avidez pelo isótopo de algumas lesões não malignas. Tais resultados falsos-positivos devem ser considerados nos casos em que se contempla a possibilidade de ressecção cirúrgica em pacientes com câncer de pulmão não confirmado.

Keywords: Tomografia por emissão de pósitrons; Tomografia computadorizada; Pulmão – lesões benignas ou congênitas; Câncer de pulmão – diagnóstico e estadiamento; Câncer de pulmão – cirurgia.

OBJETIVO: Avaliar a completude das fissuras, resposta radiológica ao tratamento e análise quantitativa por TC (AQTC) em população de pacientes com enfisema grave submetidos ao implante de valvas endobrônquicas (VEB). MATERIAIS E MÉTODOS: Foram estudados exames de TC multidetectores de 29 pacientes, realizados com protocolo de baixo dose, cortes finos, sem contraste. Dois radiologistas revisaram, retrospectivamente, os exames em consenso. A completude das fissuras foi estimada em escala de 5% e a resposta radiológica (atelectasia/perda volumétrica do lobo alvo) foi avaliada. AQTC foi realizada nos exames pré e pós-tratamento utilizando programa completamente automático. RESULTADOS: Resposta radiológica positiva foi vista em 16/29 pacientes. Os 13 pacientes sem resposta à TC apresentavam fissuras incompletas e completude média das fissuras obliquas de 72,8%, contra 88,3% no outro grupo. Os resultados mais significativos da AQTC mostraram redução do volume pulmonar (VP) total (média de 542 ml), VP tratado (700 ml) e volume de enfisema (331,4 ml) no grupo com resposta positiva, que também apresentou melhora nos testes funcionais. CONCLUSÃO: O benefício das VEB é maior em pacientes com fissuras completas e que desenvolvem atelectasia lobar. Nos pacientes sem resposta radiológica encontramos maior prevalência de fissuras incompletas e grau de incompletude das fissuras. Nossa AQTC automática detectou as alterações pós-tratamento, principalmente considerado a análise do pulmão tratado.

Keywords: Enfisema; Terapia de colapso pulmonar; Tomografia computadorizada.

OBJECTIVE: To propose a protocol for pulmonary angiography using 64-slice multidetector computed tomography (64-MDCT) with 50 mL of iodinated contrast material, in an unselected patient population, as well as to evaluate vascular enhancement and image quality. MATERIALS AND METHODS: We evaluated 29 patients (22-86 years of age). The body mass index ranged from 19.0 kg/m² to 41.8 kg/m². Patients underwent pulmonary CT angiography in a 64-MDCT scanner, receiving 50 mL of iodinated contrast material via venous access at a rate of 4.5 mL/s. Bolus tracking was applied in the superior vena cava. Two experienced radiologists assessed image quality and vascular enhancement. RESULTS: The mean density was 382 Hounsfield units (HU) for the pulmonary trunk; 379 and 377 HU for the right and left main pulmonary arteries, respectively; and 346 and 364 HU for the right and left inferior pulmonary arteries, respectively. In all patients, subsegmental arteries were analyzed. There were streak artifacts from contrast material in the superior vena cava in all patients. However, those artifacts did not impair the image analysis. CONCLUSION: Our findings suggest that pulmonary angiography using 64-MDCT with 50 mL of iodinated contrast can produce high quality images in unselected patient populations.

Keywords: Tomography, X-ray computed; Contrast media; Angiography; Pulmonary embolism.

OBJECTIVE: To perform a quantitative analysis of the lung parenchyma and pulmonary vasculature of patients with pulmonary hypertension (PH) on computed tomography angiography (CTA) images, using automated software. MATERIALS AND METHODS: We retrospectively analyzed the CTA findings and clinical records of 45 patients with PH (17 males and 28 females), in comparison with a control group of 20 healthy individuals (7 males and 13 females); the mean age differed significantly between the two groups (53 ± 14.7 vs. 35 ± 9.6 years; p = 0.0001). RESULTS: The automated analysis showed that, in comparison with the controls, the patients with PH showed lower 10th percentile values for lung density, higher vascular volumes in the right upper lung lobe, and higher vascular volume ratios between the upper and lower lobes. In our quantitative analysis, we found no differences among the various PH subgroups. We inferred that a difference in the 10th percentile values indicates areas of hypovolemia in patients with PH and that a difference in pulmonary vascular volumes indicates redistribution of the pulmonary vasculature and an increase in pulmonary vasculature resistance. CONCLUSION: Automated analysis of pulmonary vessels on CTA images revealed alterations and could represent an objective diagnostic tool for the evaluation of patients with PH.

Keywords: Hypertension, pulmonary; Tomography, X-ray computed; Image processing, computer-assisted.

OBJECTIVE: To assess the percent agreement between diagnostic imaging modalities for the evaluation of lymphadenopathies in HIV-infected/AIDS patients. MATERIALS AND METHODS: This was an open, comparative, prospective study of diagnostic imaging methods for lymphadenopathy evaluation. We evaluated 30 patients (19 men and 11 women). All underwent ultrasound and computed tomography (CT). Twenty of the patients also underwent magnetic resonance imaging (MRI). We determined the percent agreement between two examiners using the various imaging methods to evaluate lymphadenopathies. RESULTS: CT had the highest percent agreement, at 93.3%, with a kappa coefficient of 0.85, corresponding to 28 of the 30 examinations. When we compared the percent agreement between the two examiners and between CT and ultrasound, examiner 1 had an observed rate of 80.0%, with a kappa of 0.49, corresponding to 24 of the 30 examinations, whereas examiner 2 had a rate of 70.0%, with a kappa of 0.31, corresponding to 21 of the 30 examinations. Between MRI and CT, the percent agreement for examiner 1 was 50.0%, with a kappa of −0.18, corresponding to 10 of the 20 examinations, whereas that for examiner 2 was 85.0%, with a kappa of 0.69, corresponding to 17 of the 20 examinations. For MRI and ultrasound, examiner 1 had a percent agreement of 70.0%, with a kappa of 0.20, corresponding to 14 of the 20 examinations, and examiner 2 had a percent agreement of 75.0%, with a kappa of 0.38, corresponding to 15 of the 20 examinations. CONCLUSION: This study indicates that intermethod agreement is highly dependent on the way in which the research is conducted, rather than on the level of experience of the examiner.

Keywords: HIV; Acquired immunodeficiency syndrome; Lymphadenopathy; Ultrasonography; Tomography, X-ray computed; Magnetic resonance imaging..

Os nervos cranianos representam extensões das estruturas funcionais do cérebro que cruzam a cabeça e o pescoço. Eles estão ligados a diferentes estruturas cranianas e se relacionam com diversas doenças. Uma compreensão profunda de sua complexa anatomia e aparência normal de imagem permite ao examinador identificar e caracterizar com mais precisão as anormalidades. A ressonância magnética com contraste é uma importante ferramenta para avaliar essas estruturas, especialmente as sequências tridimensionais de precessão livre de estado estacionário, que proporcionam alta resolução espacial e de partes moles, apesar da fina espessura dos nervos cranianos. Na maioria dos casos, os achados de imagem são inespecíficos, e uma anamnese completa, exame físico dirigido e testes laboratoriais são necessários para estreitar o diagnóstico diferencial. Este ensaio iconográfico ilustra e discute doenças congênitas, traumáticas e vasculares dos nervos cranianos, mostrando imagens em uma abordagem fisiopatológica.

Keywords: Neuroimagem/métodos; Radiologia/métodos; Ressonância magnética/métodos; Nervos cranianos/diagnóstico por imagem.

OBJECTIVE: To assess interobserver agreement among radiologists regarding the current Fleischner Society diagnostic criteria for usual interstitial pneumonia (UIP) patterns on computed tomography (CT). MATERIALS AND METHODS: Using the Fleischner Society criteria for UIP CT patterns, five raters, working independently, categorized the high-resolution CT (HRCT) scans of 44 patients with interstitial lung disease who underwent lung biopsy. The raters also evaluated the presence, extent, and distribution of the most relevant imaging findings, as well as indicating their level of confidence in the most likely diagnosis and in up to three diagnostic hypotheses. RESULTS: There was moderate to substantial interobserver agreement regarding the UIP patterns on HRCT—kappa statistic (κ) = 0.59–0.61. Interobserver agreement for the binary scores was substantial (κ = 0.77–0.79), whereas that for the presence of honeycombing was almost perfect (κ = 0.81–0.96). There was agreement regarding at least one of the three diagnostic hypotheses in only 36.4% of the cases. For the level of confidence in the most likely diagnosis, there was only slight to fair agreement (κ = 0.19–0.21). CONCLUSION: Interobserver agreement regarding the current Fleischner Society CT criteria for UIP was moderate to substantial among raters with varying levels of experience. There was only slight to fair agreement regarding the diagnostic hypotheses and for the level of confidence in the most likely diagnosis.

Keywords: Lung diseases, interstitial/diagnosis; Tomography, X-ray computed/methods; Observer variation; Idiopathic pulmonary fibrosis/diagnostic imaging.

OBJETIVO: Avaliar os padrões tomográficos relacionados aos agentes etiológicos da pneumonia em pacientes durante o primeiro ano após transplante renal. MATERIAIS E MÉTODOS: Foram analisados dados de prontuários de 956 pacientes submetidos a transplante renal, no período de 2013 a 2018, em um centro transplantador renal do nordeste do Brasil. Nos pacientes que desenvolveram pneumonia, os agentes etiológicos foram classificados em bactérias piogênicas, micobactérias, fungos, vírus e pneumonia polimicrobiana, enquanto os padrões tomográficos foram classificados em consolidação, broncopneumonia, pneumonia intersticial e nódulos e massas. Para verificar associação estatística entre micro-organismos e padrões tomográficos, foi utilizado o teste exato de Fisher, com p < 0,001. RESULTADOS: Foram encontrados 101 casos de pneumonia, dos quais 60 (59,4%) tiveram agente etiológico identificado, sendo as bactérias piogênicas as mais frequentes, detectadas em 22 (36,7%) dos casos. Entre os pacientes com agente causal identificado, o padrão tomográfico predominante foi o de nódulos e massas, identificado em 25 (41,7%) casos. Foi observada associação entre bactérias piogênicas e o padrão de consolidação, fungos com nódulos e massas, bem como entre agentes virais e padrão intersticial. CONCLUSÃO: Foi demonstrada associação estatística entre micro-organismos causadores de pneumonia e padrões tomográficos, informação que pode contribuir para o planejamento da terapia de pacientes transplantados renais.

Keywords: Pneumonia; Transplante de rim; Tomografia computadorizada.

OBJECTIVE: To perform a quantitative assessment of bronchial wall thickening and the emphysema score in patients with stable chronic obstructive pulmonary disease (COPD), comparing the eosinophilic and non-eosinophilic COPD phenotypes. MATERIALS AND METHODS: This was a retrospective observational study of patients with COPD followed between August 2018 and July 2019. The patients were divided into two groups by the eosinophil count in peripheral blood: eosinophilic (≥ 300 cells/µL); and non-eosinophilic (< 300 cells/µL). Quantitative, automated assessments of emphysema and bronchial wall thickness were performed by evaluating computed tomography scans of the chest. RESULTS: We evaluated the records of 110 patients diagnosed with COPD: 28 (25.5%) in the eosinophilic group; and 82 (74.5%) in the non-eosinophilic group. The demographic, clinical, functional, and therapeutic variables were comparable between the two groups. There were no significant differences between the two groups in terms of the emphysema score or bronchial wall thickness (p > 0.05 for both). CONCLUSION: Patients with eosinophilic COPD do not appear to have lower emphysema scores or greater bronchial wall thickening than do those with non-eosinophilic phenotypes of the disease.

Keywords: Pulmonary disease, chronic obstructive; Eosinophils; Tomography, X-ray computed.

Cystic echinococcosis (hydatid disease) is a zoonotic parasitic disease, caused by ingestion of Echinococcus granulosus eggs, that can result in cyst formation anywhere on the body. Hydatid disease is frequently seen in regions where there is human-animal contact and poor socioeconomic development. The prevalence of the disease ranges from 0 to 79 cases/100,000 population. Hydatid cysts are typically found in the liver and lungs, being less common in other parts of the body. Computed tomography or magnetic resonance imaging is often used in order to clarify the sites affected by a hydatid cyst, such as the cranial and thoracic regions, which also facilitates the surgical evaluation and minimizes complications. Although rare, hydatid cysts in atypical locations can provoke unusual complications, with unpredictable findings and symptoms. This essay discusses the radiological aspects of rare thoracic hydatid cysts.

Keywords: Echinococcosis/diagnostic imaging; Echinococcosis, pulmonary/diagnostic imaging; Thoracic diseases/diagnostic imaging; Tomography, X-ray computed; Magnetic resonance imaging.

OBJECTIVE: To characterize the main causes of the reversed halo sign (RHS) on computed tomography (CT) of the chest and its imaging features.
MATERIALS AND METHODS: This was a retrospective study reviewing all chest CT scans for which the report contained the term "reversed halo sign" among those performed between 2015 and 2020 at a tertiary care hospital.
RESULTS: A total of 286 cases were identified, and the corresponding CT images and clinical data were reviewed. In this population, the most common cause of an RHS was pulmonary infarction (in 42%), followed by cryptogenic organizing pneumonia (in 17%) and bacterial pneumonia (in 16%). In addition, the CT characteristics of the RHS were identified in various conditions, such as pulmonary thromboembolism with pulmonary infarction, in which the RHS was typically smooth-walled and solitary with a peripheral distribution.
CONCLUSION: The RHS can be observed in many contexts, and its CT characteristics, in combination with the clinical picture, can help narrow the differential diagnosis.

Keywords: Tomography, X-ray computed/methods; Respiratory tract infections/diagnostic imaging; Pulmonary embolism/diagnostic imaging; Lung diseases, interstitial/diagnostic imaging.

OBJECTIVE: To assess the prevalence and type of residual lung abnormalities on chest computed tomography (CT) and pulmonary function testing (PFT) variables in patients with respiratory symptoms related to post-COVID-19 condition at 12 months of follow-up, and to analyze associations between CT findings and PFT parameters.
MATERIALS AND METHODS: The CT findings were evaluated by two radiologists, who calculated semiquantitative CT scores. The PFTs included spirometry, plethysmography, and the diffusing capacity of the lung for carbon monoxide.
RESULTS: Thirty-seven patients were included in the study. On CT scans of the chest acquired at 12 months of follow-up, 78.3% of the patients exhibited residual abnormalities, including reticular opacities, in 75.7%; traction bronchiectasis/bronchiolectasis, in 43.2%; and fibrosis-like findings, in 43.2%. The mean overall CT score was 9.30 ± 2.59. Patients with fibrosis-like findings had significantly lower total lung capacity (68.6% vs. 80.6% of the predicted value; p = 0.018). A moderate negative correlation was found between the overall CT score and total lung capacity (rs = −0.49; p = 0.003).
CONCLUSION: It seems that a significant proportion of patients with respiratory symptoms related to post–COVID-19 condition demonstrate residual lung abnormalities on chest CT at 12 months of follow-up, with a substantial prevalence of fibrosis-like findings. Such abnormalities are associated with restrictive lung disease.

Keywords: Post-acute COVID-19 syndrome; Tomography, X-ray computed; Pulmonary fibrosis; SARS-CoV-2; COVID-19/complications.

The objective of this systematic review and meta-analysis of observational studies was to estimate the prevalence of residual alterations in the lung parenchyma on computed tomography (CT) after coronavirus disease 2019 (COVID-19), correlating those alterations with the severity of the acute phase of the disease. We reviewed data related to adult patients evaluated at 3, 6, and 12 months after the diagnosis of moderate-to-critical COVID-19. We performed structured searches of 14 databases, encompassing works published between January 2020 and January 2024. Thus, 44 primary studies were selected. Data on mild cases of COVID-19 were excluded, as were those related to assessment of the acute phase of the disease. The results were analyzed descriptively, and meta-analyses were conducted to estimate prevalence. The estimated prevalence of altered CT scans at post-diagnosis months 3, 6, and 12 was 69.0% (95% CI: 60.0–77.6%; I² = 86%; p < 0.001), 62.0% (95% CI: 52.0–71.5%; I² = 77%; p < 0.001), and 54.0% (95% CI: 40.0–67.5%; I² = 88%; p < 0.001), respectively. There was no correlation between severity of the acute phase and the persistence of alterations on CT in general. Among the CT scans acquired at post-diagnosis month 3, alterations indicative of fibrosis were observed in 22% (95% CI: 13–30%; I² = 85%; p < 0.001), and no reduction in that prevalence was observed at the subsequent time points (rho-s = 0.952; p < 0.000). The severity of the acute phase showed a positive correlation with the presence of lesions indicative of pulmonary fibrosis on CT scans acquired at 3 months after the diagnosis of COVID-19.

Keywords: COVID-19; Tomography, X-ray computed; Post-acute COVID-19 syndrome; Thorax; Lung diseases/complications.