OBJECTIVE: The purpose of thys study was to investigate the effect of the addition of aluminum (1 mm) and copper (0.4 mm) filters on effective radiation doses and image quality in videofluoroscopy. MATERIALS AND METHODS: An ionization chamber coupled with an electrometer was added to x-ray tube to measure the kerma area product with 65 kV and 0.7 mA technique, without and with additional filtration. Low contrast, gray scale and spatial resolution were measured utilizing Leeds test objects. Fifteen volunteers underwent pharynx study, ten without and five with aluminum and cooper filters associated, and had the kerma area product/minute compared. RESULTS: The specified filters addition, either separated or associated, allowed an expressive decrease in kerma area product besides an actual improvement in the videofluoroscopic images quality determined by a better gray tones differentiation and increased brightness contrast ratio in the gray curve. CONCLUSION: Additional aluminum and copper filters interposition, especially when associated, results in improved image quality with expressive reduction in the required radiation doses.

Keywords: Videofluoroscopy, Kerma area product, X-ray, Radiological image, Radiation dose

The melanotic neuroectodermal tumor of infancy, also known as progonoma, is a rare benign disease of neural crest origin that occurs within the first year of life and affects mainly the maxilla. The authors report a case of a 10-month-old child presenting with this uncommon tumor in the maxilla, emphasizing the diagnostic findings on computed tomography, and present a literature review.

Keywords: Neoplasia, Neural crest, Maxilla, Infancy, Computed tomography

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 percepção de médicos residentes em radiologia de 4º ano sobre as melhores modalidades de imagem na investigação de neoplasias e trauma. Materiais e Métodos: Vinte e sete médicos residentes de 4º ano de quatro programas de residência em radiologia americanos participaram do estudo. Aos participantes foi perguntado sobre a melhor modalidade de imagem para se avaliar o cérebro e a coluna vertebral, pulmões, abdome e o sistema musculoesquelético. As modalidades de imagem disponíveis foram: RM, TC, ultrassonografia, PET e radiografia simples. Todos os achados foram comparados com os Critérios de Adequação de Exames de Imagem e Radioterapia do ACR. Resultados: A RM foi escolhida como melhor modalidade de imagem para se avaliar neoplasias encefálicas, espinhais, abdominais e musculoesqueléticas por 96,3%, 100%, 70,4% e 63% dos residentes, respectivamente. A TC foi escolhida por 88,9% dos residentes para avaliar neoplasias pulmonares. A modalidade de imagem ótima para se avaliar trauma foi a TC para lesões encefálicas (100%), espinhais (92,6%), pulmonares (96,3%), abdominais (92,6%) e grandes lesões traumáticas musculoesqueléticas (74,1%); a RM foi escolhida para lesões esportivas (96,3%). Observou-se concordância com os critérios de adequação do ACR. Conclusão: Houve concordância entre a percepção dos residentes sobre as melhores modalidades de imagem para avaliação de neoplasias e trauma e os critérios de adequação do ACR.

Keywords: Formação de residentes; Educação médica; Modalidades de imagem.

OBJETIVO: Este estudo teve por finalidade avaliar a perfusão miocárdica de pacientes com diabetes mellitus tipo 1 (DM1) e tipo 2 (DM2) assintomáticos, sem diagnóstico prévio de doença arterial coronariana (DAC) ou acidente vascular cerebral. MATERIAIS E MÉTODOS: Cinquenta e nove pacientes consecutivos (16 DM1, 43 DM2) foram submetidos a cintilografia de perfusão miocárdica com sestamibi-^99mTc (CPM). Foram avaliados quanto ao índice de massa corpórea, controle metabólico do diabetes, dislipidemia, terapia para o diabetes, hipertensão arterial sistêmica, nefropatia, retinopatia, neuropatia periférica, tabagismo e história familiar de DAC. RESULTADOS: CPM foi anormal em 25,4%: 12 (20,3%) com alterações de perfusão e 3 com disfunção ventricular esquerda isolada. Os mais fortes preditores de perfusão miocárdica anormal foram: idade igual ou maior a 60 anos (p = 0,017, odds ratio [OR] = 6,0), neuropatia periférica (p = 0,028, OR = 6,1), nefropatia (p = 0,031, OR = 5,6) e ECG de esforço positivo para isquemia (p = 0,049, OR = 4,08). CONCLUSÃO: A isquemia miocárdica silenciosa ocorre em mais de um em cada cinco diabéticos assintomáticos. Os mais fortes preditores de isquemia foram: idade avançada, neuropatia periférica, nefropatia, retinopatia e ECG de esforço positivo para isquemia.

Keywords: Diabetes mellitus; Cintilografia de perfusão miocárdica; Isquemia miocárdica silenciosa; Doença arterial coronariana.

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 determine whether preoperative anthropometric and computed tomography (CT) measurements of body composition can predict postoperative morbidity and mortality in patients with gastric or esophageal cancer. MATERIALS AND METHODS: This was a retrospective study in which we reviewed the medical records and abdominal CT scans of patients with gastric or esophageal cancer who underwent surgery in 2015 at a cancer center. CT scans performed during routine preoperative evaluation were retrospectively assessed to measure the area of lean body mass at the level of the third lumbar vertebra, as well as the area of visceral and subcutaneous fat. RESULTS: Seventy patients were included in the study. The mean age was 59.9 years (range, 33–82 years), and 47 patients (67.1%) were men. The mean postoperative follow-up period was 14.9 months. Neither postoperative morbidity nor postoperative mortality correlated significantly with gender, age, the type of primary tumor, the presence of comorbidities, smoking status, body mass index, nutritional status, or visceral fat area. The survival rate was higher for patients with normal lean body mass than for those with low lean body mass (hazard ratio = 0.116; 95% confidence interval: 0.015–0.906; p = 0.040). CONCLUSION: Our data suggest that lean body mass can be a relevant prognostic factor in patients with gastric or esophageal cancer, and that CT measurements should be included in the routine preoperative evaluation, because it may provide information that aids nutritional and clinical care for these patients.

Keywords: Gastrointestinal neoplasms; Stomach neoplasms; Esophageal neoplasms; Body composition; Body fat distribution; Tomography, X-ray computed.

OBJECTIVE: To determine whether the radiomic features of lung lesions on computed tomography correlate with overall survival in lung cancer patients. MATERIALS AND METHODS: This was a retrospective study involving 101 consecutive patients with malignant neoplasms confirmed by biopsy or surgery. On computed tomography images, the lesions were submitted to semi-automated segmentation and were characterized on the basis of 2,465 radiomic variables. The prognostic assessment was based on Kaplan–Meier analysis and log-rank tests, according to the median value of the radiomic variables. RESULTS: Of the 101 patients evaluated, 28 died (16 dying from lung cancer), and 73 were censored, with a mean overall survival time of 1,819.4 days (95% confidence interval [95% CI]: 1,481.2–2,157.5). One radiomic feature (the mean of the Fourier transform) presented a difference on Kaplan–Meier curves (p < 0.05). A high-risk group of patients was identified on the basis of high values for the mean of the Fourier transform. In that group, the mean survival time was 1,465.4 days (95% CI: 985.2–1,945.6), with a hazard ratio of 2.12 (95% CI: 1.01–4.48). We also identified a low-risk group, in which the mean of the Fourier transform was low (mean survival time of 2,164.8 days; 95% CI: 1,745.4–2,584.1). CONCLUSION: A radiomic signature based on the Fourier transform correlates with overall survival, representing a prognostic biomarker for risk stratification in patients with lung cancer.

Keywords: Tomography, X-ray computed; Radiographic image interpretation, computer-assisted; Lung neoplasms; Prognosis.

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 the technique, efficacy, and safety of computed tomography (CT)-guided percutaneous biopsies of head and neck masses. MATERIALS AND METHODS: This was a retrospective, single-center study of CT-guided percutaneous core-needle biopsies of head and neck masses.For the analysis of diagnostic accuracy, biopsy results were compared with the final diagnosis, which was determined by histological examination and clinical follow-up. RESULTS: We evaluated 74 biopsies performed in 68 patients.The mean age of the patients was 55.6 years.Most of the lesions (79.7%) were located in the suprahyoid region, and the maximum diameter ranged from 11 mm to 128 mm.The most common approaches were paramaxillary (in 32.4%), retromandibular (in 21.6%), and periorbital (in 14.9%).Five patients (6.8%) developed minor complications.The presence of a complication did not show a statistically significant association with any clinical, radiological, or procedure-related factor.Sufficient material for histological analysis was obtained in all procedures.Thirty-eight biopsies (51.4%) yielded a histological diagnosis of malignancy.There was a false-negative result in three cases (8.3%), and there were no false-positive results.The procedure had a sensitivity of 92.7%, a specificity of 100%, and an accuracy of 96.0%. CONCLUSION: Our results demonstrate that CT-guided percutaneous core-needle biopsy of head and neck lesions is a safe, effective procedure for obtaining biological material for histological analysis.

Keywords: Image-guided biopsy; Needle biopsy; Tomography, X-ray computed; Head and neck neoplasms.

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.

OBJECTIVE: To evaluate a radiomics workflow applied to chest computed tomography (CT), examining its feasibility and performance across the steps of lung lesion segmentation, feature extraction, and clustering, as well as exploring its potential to distinguish between benign and malignant lung lesions.
MATERIALS AND METHODS: This was a retrospective study including CT images of 32 histopathology-confirmed lesions (11 benign; 21 malignant). Lesions were segmented by using syngo.via Frontier Radiomics software, after which > 900 radiomic features were extracted with the same software. Data processing—including normalization, dimensionality reduction (principal component analysis), and unsupervised (k-means) clustering—was conducted in Python.
RESULTS: The best clustering solution was obtained with a k = 2 (silhouette score = 0.4668), effectively separating benign lesions, which exhibited low heterogeneity, from malignant lesions, which exhibited complex patterns of texture and shape.
CONCLUSION: The application of a radiomics workflow proved feasible and potentially useful for differentiating between benign and malignant lung lesions on CT, underscoring its value as a complementary tool in thoracic oncology. However, future studies using multicenter datasets, blinded evaluations, and more structured integration environments are warranted in order to support clinical validation and prototyping.

Keywords: Radiomics; Lung neoplasms; Tomography, X-ray computed; Radiographic image interpretation, computer-assisted; Cluster analysis; Biomarkers; Machine learning.