Complicações dos transplantes pulmonares na tomografia computadorizada: ensaio iconográfico / Complications of lung transplantation on computed tomography: pictorial essay

Resumo Transplantes pulmonares são procedimentos progressivamente mais realizados em todo o mundo como opção para tratamento de doenças pulmonares em estágio terminal. Apesar dos avanços laboratoriais, da técnica cirúrgica e da seleção de doadores e receptores, a mortalidade nesses procedimentos ainda é significativa, em razão de complicações típicas dos pacientes transplantados. Este trabalho consiste em uma revisão da literatura acerca do tema, ilustrando as complicações abordadas por meio de imagens de tomografia computadorizada.

Abstract Lung transplantation is becoming increasingly more common as an alternative treatment for end-stage lung disease. Despite advances in laboratory testing, surgical technique, and donor/recipient selection, lung transplantation is still associated with significant mortality, due to postoperative complications. This paper consists of a brief review of postoperative complications in lung transplant recipients, illustrating those complications with computed tomography images.

Musculoskeletal pitfalls in 68Ga-PSMA PET/CT / Pitfalls do sistema musculoesquelético na PET/CT com 68Ga-PSMA

Abstract Prostate-specific membrane antigen (PSMA) is a transmembrane protein expressed in normal prostate cells and overexpressed in prostate cancer. Consequently, it is an important tool in the evaluation of prostate cancer, including the staging of high-risk patients and the assessment of biochemical recurrence. Despite the "specific" designation, benign musculoskeletal conditions, such as fractures, osteodegenerative changes, and fibrous dysplasia, can also show PSMA uptake, which can lead to misinterpretation of the imaging findings. Therefore, radiologists must be aware of these potential pitfalls, understand their causes, and fully analyze their morphologic features on unfused computed tomography (CT) and magnetic resonance imaging scans to correctly interpret the examination. In this pictorial essay, we review the basic characteristics of the 68Ga-PSMA positron-emission tomography/CT (PET/CT) radiotracer, discuss potential causes of false-positive findings on 68Ga-PSMA PET/CT in the musculoskeletal system, and illustrate the corresponding imaging findings.

Resumo O antígeno de membrana próstata específico (PSMA) é uma proteína transmembrana que apresenta expressão em células prostáticas normais e superexpressão em neoplasia da próstata. Dessa forma, é uma importante ferramenta na avaliação da neoplasia prostática, de utilidade no estadiamento de pacientes de alto risco e na análise de recorrência bioquímica. Apesar do termo "específico", condições musculoesqueléticas benignas podem demonstrar captação de PSMA, como fraturas, alterações osteodegenerativas e displasia fibrosa, podendo levar a uma avaliação equivocada dos achados de imagem. Assim, o radiologista deve conhecer esses potenciais pitfalls, compreender suas causas e analisar as características morfológicas nas imagens não fundidas de TC e RM para interpretar corretamente o exame. Neste ensaio iconográfico, revisaremos as características básicas do radiofármaco 68Ga-PSMA PET/CT, discutiremos possíveis causas de resultados falso-positivos na 68Ga-PSMA PET/CT no sistema musculoesquelético e ilustraremos os achados de imagem correspondentes.

Computed tomography angiography in the planning of transcatheter aortic valve replacement: a step-by-step approach / Angiotomografia computadorizada no planejamento de substituição transcateter da válvula aórtica: uma abordagem passo a passo

Abstract Aortic valve stenosis is the most common acquired valvular heart disease. Transcatheter aortic valve implantation, also known as transcatheter aortic valve replacement (TAVR), is an important treatment option for symptomatic aortic stenosis in patients at any level of surgical risk. The role of computed tomography angiography (CTA) has expanded considerably in recent years, and it has now become the imaging method of choice for the planning of TAVR. Therefore, radiologists should understand the main aspects of this imaging modality, including the appropriate technique and protocol to acquire reliable CTA images and to create a useful radiology report. The aim of this study was to review the most important aspects of CTA for TAVR planning.

Resumo A estenose da válvula aórtica é a doença cardíaca valvar adquirida mais comum. A substituição transcateter da válvula aórtica (TAVR), ou implante transcateter da válvula aórtica, é uma importante opção no tratamento da estenose aórtica sintomática, independente do risco cirúrgico do paciente. O papel da angiotomografia computadorizada cresceu consideravelmente nos últimos anos e tornou-se o método de escolha no planejamento de TAVR. Assim, o radiologista deve compreender os principais aspectos dessa modalidade, incluindo técnica e protocolo, a fim de adquirir imagens confiáveis e compor um relatório para a realização do procedimento. O objetivo deste ensaio é revisar os pontos mais importantes que precisam ser avaliados na angiotomografia no planejamento de TAVR.

Prognostic factors of worse outcome for hospitalized COVID-19 patients, with emphasis on chest computed tomography data: a retrospective study

ABSTRACT Objective: To evaluate anthropometric and clinical data, muscle mass, subcutaneous fat, spine bone mineral density, extent of acute pulmonary disease related to COVID-19, quantification of pulmonary emphysema, coronary calcium, and hepatic steatosis using chest computed tomography of hospitalized patients with confirmed diagnosis of COVID-19 pneumonia and verify its association with disease severity. Methods: A total of 123 adults hospitalized due to COVID-19 pneumonia were enrolled in the present study, which evaluated the anthropometric, clinical and chest computed tomography data (pectoral and paravertebral muscle area and density, subcutaneous fat, thoracic vertebral bodies density, degree of pulmonary involvement by disease, coronary calcium quantification, liver attenuation measurement) and their association with poorer prognosis characterized through a combined outcome of intubation and mechanical ventilation, need of intensive care unit, and death. Results: Age (p=0.013), body mass index (p=0.009), lymphopenia (p=0.034), and degree of pulmonary involvement of COVID-19 pneumonia (p<0.001) were associated with poor prognosis. Extent of pulmonary involvement by COVID-19 pneumonia had an odds ratio of 1,329 for a poor prognosis and a cutoff value of 6.5 for increased risk, with a sensitivity of 64.9% and specificity of 67.1%. Conclusion: The present study found an association of high body mass index, older age, extent of pulmonary involvement by COVID-19, and lymphopenia with severity of COVID-19 pneumonia in hospitalized patients.

The role of the radiologist in the assessment of thoracic changes after radiotherapy / O papel do radiologista na avaliação das alterações torácicas após radioterapia

Abstract Radiotherapy plays a central role in the palliative and curative treatment of neoplasms of the chest wall or intrathoracic structures. However, despite technical advances, radiotherapy can alter previously normal organs and tissues, those alterations presenting as various types of imaging findings. Post-radiation alterations must be promptly recognized by radiologists, in order to avoid confusion between complications of radiotherapy and the recurrence of a tumor. This pictorial essay aims to illustrate different thoracic changes after radiotherapy.

Resumo A radioterapia tem papel fundamental no tratamento curativo ou paliativo de neoplasias da parede torácica ou intratorácicas. No entanto, mesmo com o avanço das técnicas, órgãos e tecidos vizinhos podem ser acometidos e apresentar alterações que devem ser reconhecidas pelos radiologistas, de maneira a evitar confusão com recidiva das lesões inicialmente tratadas, ou mesmo com outras complicações do tratamento oncológico. O objetivo deste ensaio iconográfico é ilustrar as diferentes consequências torácicas da radioterapia.

Evaluation of the RSNA and CORADS classifications for COVID-19 on chest computed tomography in the Brazilian population

OBJECTIVE: To determine the correlation between the two tomographic classifications for coronavirus disease (COVID-19), COVID-19 Reporting and Data System (CORADS) and Radiological Society of North America Expert Consensus Statement on Reporting Chest Computed Tomography (CT) Findings Related to COVID-19 (RSNA), in the Brazilian population and to assess the agreement between reviewers with different experience levels. METHODS: Chest CT images of patients with reverse transcriptase-polymerase chain reaction (RT-PCR)-positive COVID-19 were categorized according to the CORADS and RSNA classifications by radiologists with different levels of experience and who were initially unaware of the RT-PCR results. The inter- and intra-observer concordances for each of the classifications were calculated, as were the concordances between classifications. RESULTS: A total of 100 patients were included in this study. The RSNA classification showed an almost perfect inter-observer agreement between reviewers with similar experience levels, with a kappa coefficient of 0.892 (95% confidence interval [CI], 0.788-0.995). CORADS showed substantial agreement among reviewers with similar experience levels, with a kappa coefficient of 0.642 (95% CI, 0.491-0.793). There was inter-observer variation when comparing less experienced reviewers with more experienced reviewers, with the highest kappa coefficient of 0.396 (95% CI, 0.255-0.588). There was a significant correlation between both classifications, with a Kendall coefficient of 0.899 (p<0.001) and substantial intra-observer agreement for both classifications. CONCLUSION: The RSNA and CORADS classifications showed excellent inter-observer agreement for reviewers with the same level of experience, although the agreement between less experience reviewers and the reviewer with the most experience was only reasonable. Combined analysis of both classifications with the first RT-PCR results did not reveal any false-negative results for detecting COVID-19 in patients.

Differential diagnoses of acute ground-glass opacity in chest computed tomography: pictorial essay / Diagnósticos diferenciais de opacidade em vidro fosco aguda na tomografia computadorizada de tórax: ensaio pictórico

ABSTRACT Ground-glass opacity is a very frequent and unspecified finding in chest computed tomography. Therefore, it admits a wide range of differential diagnoses in the acute context, from viral pneumonias such as influenza virus, coronavirus disease 2019 and cytomegalovirus and even non-infectious lesions, such as vaping, pulmonary infarction, alveolar hemorrhage and pulmonary edema. For this diagnostic differentiation, ground glass must be correlated with other findings in imaging tests, with laboratory tests and with the patients' clinical condition. In the context of a pandemic, it is extremely important to remember the other pathologies with similar findings to coronavirus disease 2019 in the imaging exams.

RESUMO A opacidade em vidro fosco é uma alteração muito frequente e pouco específica na tomografia computadorizada de tórax. Ela admite grande leque de diagnósticos diferenciais no contexto agudo, desde pneumonias virais, como as causadas pelo vírus influenza, pela doença do coronavírus 2019 e pelo citomegalovírus, até mesmo lesões de origem não infecciosa, como vaping , infarto pulmonar, hemorragia alveolar e edema pulmonar. Para essa diferenciação diagnóstica, deve-se correlacionar o vidro fosco com os demais achados nos exames de imagem, exames laboratoriais e quadro clínico do paciente. É de suma importância, no contexto de pandemia, recordar as demais patologias com os achados semelhantes aos da doença do coronavírus 2019 nos exames de imagem.

Lung lesion burden found on chest ct as a prognostic marker in hospitalized patients with high clinical suspicion of COVID-19 pneumonia: a brazilian experience

OBJECTIVE: To investigate the relationship between lung lesion burden (LLB) found on chest computed tomography (CT) and 30-day mortality in hospitalized patients with high clinical suspicion of coronavirus disease 2019 (COVID-19), accounting for tomographic dynamic changes. METHODS: Patients hospitalized with high clinical suspicion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a dedicated and reference hospital for COVID-19, having undergone at least one RT-PCR test, regardless of the result, and with one CT compatible with COVID-19, were retrospectively studied. Clinical and laboratory data upon admission were assessed, and LLB found on CT was semi-quantitatively evaluated through visual analysis. The primary outcome was 30-day mortality after admission. Secondary outcomes, including the intensive care unit (ICU) admission, mechanical ventilation used, and length of stay (LOS), were assessed. RESULTS: A total of 457 patients with a mean age of 57±15 years were included. Among these, 58% presented with positive RT-PCR result for COVID-19. The median time from symptom onset to RT-PCR was 8 days [interquartile range 6-11 days]. An initial LLB of ≥50% using CT was found in 201 patients (44%), which was associated with an increased crude at 30-day mortality (31% vs. 15% in patients with LLB of <50%, p<0.001). An LLB of ≥50% was also associated with an increase in the ICU admission, the need for mechanical ventilation, and a prolonged LOS after adjusting for baseline covariates and accounting for the CT findings as a time-varying covariate; hence, patients with an LLB of ≥50% remained at a higher risk at 30-day mortality (adjusted hazard ratio 2.17, 95% confidence interval 1.47-3.18, p<0.001). CONCLUSION: Even after accounting for dynamic CT changes in patients with both clinical and imaging findings consistent with COVID-19, an LLB of ≥50% might be associated with a higher risk of mortality.

Chest computed tomography in the diagnosis of COVID-19 in patients with false negative RT-PCR / Tomografia computadorizada de tórax no diagnóstico de COVID-19 em pacientes com resultado falso-negativo na RT-PCR

ABSTRACT Objective To evaluate the role of chest computed tomography in patients with COVID-19 who presented initial negative result in reverse transcriptase-polymerase chain reaction (RT-PCR). Methods A single-center, retrospective study that evaluated 39 patients with negative RT-PCR for COVID-19, who underwent chest computed tomography and had a final clinical or serological diagnosis of COVID-19. The visual tomographic classification was evaluated according to the Consensus of the Radiological Society of North America and software developed with artificial intelligence for automatic detection of findings and chance estimation of COVID-19. Results In the visual tomographic analysis, only one of them (3%) presented computed tomography classified as negative, 69% were classified as typical and 28% as indeterminate. In the evaluation using the software, only four (about 10%) had a probability of COVID-19 <25%. Conclusion Computed tomography can play an important role in management of suspected cases of COVID-19 with initial negative results in RT-PCR, especially considering those patients outside the ideal window for sample collection for RT-PCR.

RESUMO Objetivo Avaliar o papel da tomografia computadorizada de tórax em pacientes com COVID-19 que apresentaram reação em cadeia da polimerase via transcriptase reversa (RT-PCR) inicial falsamente negativa. Métodos Estudo retrospectivo de centro único que avaliou 39 pacientes com RT-PCR negativa para COVID-19, submetidos à tomografia computadorizada de tórax e que tiveram diagnóstico final clínico ou serológico de COVID-19. A classificação tomográfica visual foi avaliada de acordo com o Consenso da Radiological Society of North America e o software desenvolvido com inteligência artificial para detecção automática de achados e estimativa de probabilidade de COVID-19. Resultados Na análise tomográfica visual, somente um deles (3%) apresentou tomografia computadorizada classificada como tendo resultado negativo, 69% foram classificados como típicos e 28% como indeterminados. Na avaliação com uso de software, somente quatro (cerca de 10%) tiveram probabilidade de COVID-19 <25%. Conclusão A tomografia computadorizada pode desempenhar papel importante no manejo de casos suspeitos de COVID-19 com RT-PCR inicialmente negativa, principalmente levando-se em consideração os pacientes que estão fora da janela ideal para coleta de amostra para RT-PCR.

Magnetic resonance imaging aspects after surgical repair of knee cartilage: pictorial essay / Aspectos na ressonância magnética pós-reparo cirúrgico da cartilagem do joelho: ensaio iconográfico

Abstract Radiologists should be familiar with the main techniques of knee cartilage repair and the imaging methods available for its evaluation, in order to optimize the postoperative follow-up of patients. The objective of this study was to present a series of clinical cases seen at our facility, illustrating the main techniques necessary for the repair of knee cartilage, as well as the magnetic resonance imaging techniques used in the postoperative evaluation and the relevant radiological findings.

Resumo Radiologistas devem estar familiarizados com as principais técnicas de reparo cirúrgico da cartilagem do joelho e os métodos de imagem disponíveis para sua avaliação, no intuito de otimizar o seguimento pós-operatório do paciente. O presente estudo tem por finalidade, por meio de uma coletânea de casos do nosso serviço, ilustrar as principais técnicas cirúrgicas aplicadas ao reparo da cartilagem do joelho, bem como as técnicas de ressonância magnética usualmente utilizadas na avaliação pós-operatória e os achados radiológicos relevantes.

Main complications of hip arthroplasty: pictorial essay / Principais complicações da artroplastia de quadril: ensaio iconográfico

Abstract Hip arthroplasty is a widely used and successful orthopedic procedure for the treatment of degenerative, inflammatory, or traumatic joint disease. The procedure promotes significant pain relief, as well as recovery of limb function, reduction of disability, and better quality of life. However, there are related complications, which have characteristic imaging aspects. In the present study, we review the literature and exemplify such complications using images obtained at our facility, illustrating the main radiological aspects of complications such as heterotopic ossification, periprosthetic fractures, osteolysis, infection, wear, and dislocation.

Resumo A artroplastia de quadril é um procedimento cirúrgico ortopédico amplamente utilizado e de grande sucesso para tratamento da doença articular, seja esta degenerativa, inflamatória ou traumática, promovendo importante melhora da dor, recuperação da função do membro, redução da incapacidade e melhora da qualidade de vida. Entretanto, existem complicações relacionadas, as quais possuem aspectos de imagem característicos. O presente estudo revisou a literatura e exemplificou essas complicações de forma ilustrativa com a experiência do nosso serviço, abordando os principais aspectos radiológicos das complicações da artroplastia de quadril, englobando ossificação heterotópica, fraturas periprotéticas, osteólise, infecção, desgaste e luxação.

Imaging findings in COVID-19 pneumonia

The coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in Wuhan city and was declared a pandemic in March 2020. Although the virus is not restricted to the lung parenchyma, the use of chest imaging in COVID-19 can be especially useful for patients with moderate to severe symptoms or comorbidities. This article aimed to demonstrate the chest imaging findings of COVID-19 on different modalities: chest radiography, computed tomography, and ultrasonography. In addition, it intended to review recommendations on imaging assessment of COVID-19 and to discuss the use of a structured chest computed tomography report. Chest radiography, despite being a low-cost and easily available method, has low sensitivity for screening patients. It can be useful in monitoring hospitalized patients, especially for the evaluation of complications such as pneumothorax and pleural effusion. Chest computed tomography, despite being highly sensitive, has a low specificity, and hence cannot replace the reference diagnostic test (reverse transcription polymerase chain reaction). To facilitate the confection and reduce the variability of radiological reports, some standardizations with structured reports have been proposed. Among the available classifications, it is possible to divide the radiological findings into typical, indeterminate, atypical, and negative findings. The structured report can also contain an estimate of the extent of lung involvement (e.g., more or less than 50% of the lung parenchyma). Pulmonary ultrasonography can also be an auxiliary method, especially for monitoring hospitalized patients in intensive care units, where transfer to a tomography scanner is difficult.