Objectives: To evaluate the performance of a computer program designed to facilitate the detection of pulmonary nodules using multidetector computed tomography (MDCT) scans of the chest. Methods: We evaluated 24 consecutive MDCT scans of the chest at the Fleury Diagnostic Imaging Center during the period from October 7 to October 19 of 2006, using a 64-channel CT scanner. The study comprised 12 females and 12 males, ranging from 35 to 77 years of age (mean, 57.9 years). Double reading and a computer-aided diagnosis (CAD) system were used in order to perform two independent analyses of the data. The nodules found using both methods were recorded, and the data were compared. Results: The total sensitivity of CAD for the detection of nodules was 16.5%, increasing to 55% when nodules <4 mm in diameter were excluded. Sensitivity by diameter was 6.5% for nodules <4 mm, 45% for nodules of 4-6 mm, 100% for nodules of 6 mm-1 cm, and 0% for nodules >1 cm. More than 99% of true nodules detected by CAD were registered in the image double-reading process. Conclusions: In this preliminary 24-case study, the sensitivity of computer program tested was not significantly greater than that of the double-reading process that is routinely performed in this facility.

Keywords: Image interpretation, computer-assisted; Coin lesion, pulmonary; Tomography, X-ray computed.

Introduction: At present, chest radiography (CR) is the main instrument used in the diagnosis of silicosis, following the International Labor Organization (ILO) recommendations. In incipient cases, the interpretation of radiographs is difficult and disagreement may occur, even among experienced readers. Recently, the possibility of evaluating incipient cases by using high resolution computed tomography (HRCT) has been considered. Objective: To compare CR with HRCT results. Patients and methods: An original group of 135 ex-miners were evaluated by CR, according to ILO recommendations, examined by three readers, from November 1997 to December 1999. HRCT was indicated to 68 patients whose median profusion readings was 1/0 or below. HRCT results were examined by two readers and, in cases of disagreement, a third reader was consulted. HRCT results were classified according to micronodule profusion into categories 0 to 3. CR and HRCT results were compared using McNemar test, weighed Kappa coefficient and log-linear models. Results and conclusion: There was good agreement among the methods in category 0, so it was concluded that both methods are similar in excluding the diagnosis of silicosis. However, in category 1 or greater (diagnosis of the disease) a good agreement among the methods was not observed.

Keywords: Silicosis. Thoracic radiography. Tomography X-ray computed. Pneumoconiosis.

Objective: To compare the performance of nested polymerase chain reaction (NPCR) with that of cultures in the detection of the Mycobacterium tuberculosis complex in pulmonary and extrapulmonary specimens. Methods: We analyzed 20 and 78 pulmonary and extrapulmonary specimens, respectively, of 67 hospitalized patients suspected of having tuberculosis. An automated microbial system was used for the identification of Mycobacterium spp. cultures, and M. tuberculosis IS6110 was used as the target sequence in the NPCR. The kappa statistic was used in order to assess the level of agreement among the results. Results: Among the 67 patients, 6 and 5, respectively, were diagnosed with pulmonary and extrapulmonary tuberculosis, and the NPCR was positive in all of the cases. Among the 98 clinical specimens, smear microscopy, culture, and NPCR were positive in 6.00%, 8.16%, and 13.26%, respectively. Comparing the results of NPCR with those of cultures (the gold standard), we found that NPCR had a sensitivity and specificity of 100% and 83%, respectively, in pulmonary specimens, compared with 83% and 96%, respectively, in extrapulmonary specimens, with good concordance between the tests (kappa, 0.50 and 0.6867, respectively). Conclusions: Although NPCR proved to be a very useful tool for the detection of M. tuberculosis complex, clinical, epidemiological, and other laboratory data should also be considered in the diagnosis and treatment of pulmonary and extrapulmonary tuberculosis.

Keywords: Tuberculosis/diagnosis; Tuberculosis/microbiology; Mycobacterium tuberculosis; Polymerase chain reaction.

New non-invasive methods have been developed to detect lung malignancies. One of them is positron emission tomography (PET) using 18F 2-deoxy-D-glucose (FDG) as a radiotracer. Objective: Evaluate the FDG-PET results performed through a hybrid coincidence-gamma camera in patients with pleuropulmonary infectious diseases or lung tumors. Material and methods: Fifteen patients were evaluated, and divided into: group I - five patients with active lung tuberculosis, and group II - ten patients with possible pleuropulmonary neoplasia. Doses of 185 MBq of FDG were given intravenously, and scans were performed with a two-headed ADAC Vertex Plus camera. Results: In group I all scans were positive. In group II after thoracotomy in nine patients and mediastinoscopy in one, the following diagnoses were observed: two adenocarcinomas, two granulomas, one small cell carcinoma, one large cell carcinoma, one hamartoma, one rounded atelectasis, one mesothelioma, and one antracosis. The scans were positive in six patients (five malignant neoplasias and one granuloma) and negative in the other four cases. Conclusion: The FDG-PET performed through a hybrid camera produces images of quality that permit identification of active infectious process. FDG-PET in association with clinical and radiological exams can differentiate malignant from benign lung neoplasias.

Keywords: emission-computed tomography, lung neoplasms, lung diseases

Objective: To evaluate the combined impact of videofluoroscopic swallow study (VFSS) and therapeutic feeding and swallowing interventions on clinical outcomes in children with oropharyngeal dysphagia (OPD). Methods: This was an uncontrolled longitudinal analytical study in which OPD patients were evaluated before and after VFSS. Children = 24 months of age diagnosed with OPD in a clinical setting and undergoing VFSS for investigation and management of OPD were included in the study. The study participants received therapeutic feeding and swallowing interventions after having undergone VFSS, being followed at an outpatient clinic for pediatric dysphagia in order to monitor feeding and swallowing difficulties. Respiratory and feeding outcomes were compared before and after VFSS. Results: Penetration/aspiration events were observed in 61% of the VFSSs (n = 72), and therapeutic feeding and swallowing interventions were recommended for 97% of the study participants. After the VFSS, there was a reduction in the odds of receiving antibiotic therapy (OR = 0.007) and in the duration of antibiotic therapy (p = 0.014), as well as in the odds of being admitted to hospital (p = 0.024) and in the length of hospital stay (p = 0.025). A combination of oral and enteral feeding became more common than oral or enteral feeding alone (p = 0.002). Conclusions: A high proportion of participants exhibited penetration/aspiration on VFSS. Therapeutic feeding and swallowing interventions following a VFSS appear to be associated with reduced respiratory morbidity in this population.

Keywords: Fluoroscopy; Deglutition disorders; Respiratory tract diseases; Pneumonia, aspiration; Nutritional support.

Objective: To identify the risk factors for pulmonary complications after thoracotomy for the resection of pulmonary nodules in patients with sarcoma. Methods: A retrospective cohort study involving 68 consecutive patients diagnosed with sarcoma and submitted to a total of 174 thoracotomies for the resection of pulmonary nodules. The dependent variable was defined as the occurrence of any postoperative pulmonary complications. The independent variables were related to the patient, underlying diagnosis, and type of surgical procedure. We analyzed the data using a multivariate generalized estimating equations model with logistic link function and a symmetric correlation structure. Results: Complications were observed in 24 patients (13.8%, 95% CI: 9.0-19.8), and there was one death. The mean length of hospital stay was twice as long in the patients with postoperative complications as in those without (18.8 ± 10.0 days vs. 8.6 ± 6.0 days; p < 0.05). The variables that correlated with the outcome measure were the type of resection (wedge vs. anatomic; OR = 3.6; 95% CI: 1.5-8.8), the need for blood transfusion (OR = 9.8; 95% CI: 1.6-60.1), and the number of nodules resected (OR = 1.1; 95% CI: 1.0-1.1). The multivariate model showed an area under the ROC curve of 0.75 (95% CI: 0.65-0.85). Conclusions: Postoperative pulmonary complications were common after pulmonary nodule resection in patients with sarcoma, occurring in approximately 10% of the procedures. The occurrence of such complications can be expected when techniques other than wedge resection are employed, when blood transfusion is required, and when a great number of nodules are resected. Therefore, it is possible to identify patients at risk for pulmonary complications, who should be closely monitored in the immediate postoperative period. In such patients, all preventive measures should be taken.

Keywords: Sarcoma; Neoplasm metastasis; Risk; Thoracotomy; Thoracic surgery.

Objective: Respiratory infections constitute a major cause of morbidity and mortality in solid organ transplant recipients. The incidence of pulmonary tuberculosis is high among such patients. On imaging, tuberculosis has various presentations. Greater understanding of those presentations could reduce the impact of the disease by facilitating early diagnosis. Therefore, we attempted to describe the HRCT patterns of pulmonary tuberculosis in lung transplant recipients. Methods: From two hospitals in southern Brazil, we collected the following data on lung transplant recipients who developed pulmonary tuberculosis: gender; age; symptoms; the lung disease that led to transplantation; HRCT pattern; distribution of findings; time from transplantation to pulmonary tuberculosis; and mortality rate. The HRCT findings were classified as miliary nodules; cavitation and centrilobular nodules with a tree-in-bud pattern; ground-glass attenuation with consolidation; mediastinal lymph node enlargement; or pleural effusion. Results: We evaluated 402 lung transplant recipients, 19 of whom developed pulmonary tuberculosis after transplantation. Among those 19 patients, the most common HRCT patterns were ground-glass attenuation with consolidation (in 42%); cavitation and centrilobular nodules with a tree-in-bud pattern (in 31.5%); and mediastinal lymph node enlargement (in 15.7%). Among the patients with cavitation and centrilobular nodules with a tree-in-bud pattern, the distribution was within the upper lobes in 66.6%. No pleural effusion was observed. Despite treatment, one-year mortality was 47.3%. Conclusions: The predominant HRCT pattern was ground-glass attenuation with consolidation, followed by cavitation and centrilobular nodules with a tree-in-bud pattern. These findings are similar to those reported for immunocompetent patients with pulmonary tuberculosis and considerably different from those reported for AIDS patients with the same disease.

Keywords: Lung transplantation; Diagnostic imaging; Mycobacterium infections; Thoracic diseases; Tomography, X-Ray computed/methods; Tuberculosis, pulmonary.

Emphysema is a condition of the lung, characterized by the abnormal increase in the size of the airspace distal to the terminal bronchioles. Currently, emphysema is the fourth leading cause of death in the USA, affecting 14 million people. The present article describes the principal tools in the imaging diagnosis of emphysema, from the early days until the present. We describe traditional techniques, such as chest X-ray, together with the evolution of computed tomography (CT) to more advanced forms, such as high resolution CT, as well as three-dimensional CT densitometry and volumetric assessment.

Keywords: Emphysema; Radiology; Tomography, X-Ray computed; Radiography, thoracic.

Objective: To investigate the effects of quercetin in a model of bleomycin-induced pulmonary inflammation and fibrosis. Methods: Seventynine adult male hamsters were randomized to receive intratracheal (IT) instillations and intraperitoneal (IP) injections in four configurations: IP vehicle/IT saline (VS group, n = 16); IP quercetin/IT saline (QS group, n = 16); IP vehicle/IT bleomycin (VB group, n = 27); and IP quercetin/ IT bleomycin (QB group, n = 20). Quercetin and bleomycin were administered at 30 mg/kg/day and 10 U/kg, respectively. Quercetin was started/discontinued 3 days before/14 days after the IT instillations. Results: The mortality rate was significantly higher in the VB group than in the other groups (44% vs. VS: 0%; QS: 0%; and QB: 15%). Lung levels of thiobarbituric acid reactive substances (× 10−2 nmol/mg) were significantly higher in the VB group (6.6 ± 1.3 vs. VS: 5.5 ± 0.8; QS: 2.5 ± 0.6; and QB: 5.8 ± 0.6). Lung levels of reduced glutathione (× 10−2 nmol/mg) were significantly lower in the VB/QB groups than in the VS/QS groups (28.9 ± 13.8/28.6 ± 14.8 vs. 43.9 ± 16.0/51.1 ± 20.3), whereas those of hydroxyproline (mg/g) were significantly higher (201.6 ± 37.3/177.6 ± 20.3 vs. 109.6 ± 26.1/117.5 ± 32.0).Mean lung septal thickness (μm) was greatest in the VB group (16.9 ± 3.2 vs. VS: 3.0 ± 0.3; QS: 3.3 ± 0.2; and QB: 5.2 ± 1.1). Conclusions: In a hamster model of lung injury, quercetin exhibited anti-inflammatory effects that are related, at least in part, to its antioxidant properties.

Keywords: Pulmonary fibrosis; Bleomycin; Flavonoids; Lipid peroxidation.

Due to the increasing number and improved survival of lung transplant recipients, radiologists should be aware of the imaging features of the postoperative complications that can occur in such patients. The early treatment of complications is important for the long-term survival of lung transplant recipients. Frequently, HRCT plays a central role in the investigation of such complications. Early recognition of the signs of complications allows treatment to be initiated earlier, which improves survival. The aim of this pictorial review was to demonstrate the CT scan appearance of pulmonary complications such as reperfusion edema, acute rejection, infection, pulmonary thromboembolism, chronic rejection, bronchiolitis obliterans syndrome, cryptogenic organizing pneumonia, post-transplant lymphoproliferative disorder, bronchial dehiscence and bronchial stenosis.

Keywords: Tomography, X-ray computed; Lung transplantation; Postoperative complications.

Objective: To investigate the detection of subsolid nodules (SSNs) on chest CT scans of outpatients before and during the COVID-19 pandemic, as well as to correlate the imaging findings with epidemiological data. We hypothesized that (pre)malignant nonsolid nodules were underdiagnosed during the COVID-19 pandemic because of an overlap of imaging findings between SSNs and COVID-19 pneumonia. Methods: This was a retrospective study including all chest CT scans performed in adult outpatients (> 18 years of age) in September of 2019 (i.e., before the COVID-19 pandemic) and in September of 2020 (i.e., during the COVID-19 pandemic). The images were reviewed by a thoracic radiologist, and epidemiological data were collected from patient-filled questionnaires and clinical referrals. Regression models were used in order to control for confounding factors. Results: A total of 650 and 760 chest CT scans were reviewed for the 2019 and 2020 samples, respectively. SSNs were found in 10.6% of the patients in the 2019 sample and in 7.9% of those in the 2020 sample (p = 0.10). Multiple SSNs were found in 23 and 11 of the patients in the 2019 and 2020 samples, respectively. Women constituted the majority of the study population. The mean age was 62.8 ± 14.8 years in the 2019 sample and 59.5 ± 15.1 years in the 2020 sample (p < 0.01). COVID-19 accounted for 24% of all referrals for CT examination in 2020. Conclusions: Fewer SSNs were detected on chest CT scans of outpatients during the COVID-19 pandemic than before the pandemic, although the difference was not significant. In addition to COVID-19, the major difference between the 2019 and 2020 samples was the younger age in the 2020 sample. We can assume that fewer SSNs will be detected in a population with a higher proportion of COVID-19 suspicion or diagnosis.

Keywords: Solitary pulmonary nodule; Multiple pulmonary nodules; Lung neoplasms/diagnostic imaging; Tomography, X-ray computed; COVID-19.

Objective: To determine the incidence of the reversed halo sign (RHS) in patients with pulmonary infarction (PI) due to acute pulmonary embolism (PE), detected by computed tomography angiography (CTA) of the pulmonary arteries, and to describe the main morphological features of the RHS. Methods: We evaluated 993 CTA scans, stratified by the risk of PE, performed between January of 2010 and December of 2014. Although PE was detected in 164 scans (16.5%), three of those scans were excluded because of respiratory motion artifacts. Of the remaining 161 scans, 75 (46.6%) showed lesions consistent with PI, totaling 86 lesions. Among those lesions, the RHS was seen in 33 (38.4%, in 29 patients). Results: Among the 29 patients with scans showing lesions characteristic of PI with the RHS, 25 (86.2%) had a single lesion and 4 (13.8%) had two, totaling 33 lesions. In all cases, the RHS was in a subpleural location. To standardize the analysis, all images were interpreted in the axial plane. Among those 33 lesions, the RHS was in the right lower lobe in 17 (51.5%), in the left lower lobe in 10 (30.3%), in the lingula in 5 (15.2%), and in the right upper lobe in 1 (3.0%). Among those same 33 lesions, areas of low attenuation were seen in 29 (87.9%). The RHS was oval in 24 (72.7%) of the cases and round in 9 (27.3%). Pleural effusion was seen in 21 (72.4%) of the 29 patients with PI and the RHS. Conclusions: A diagnosis of PE should be considered when there are findings such as those described here, even in patients with nonspecific clinical symptoms.

Keywords: Pulmonary embolism; Pulmonary infarction; Computed tomography angiography.

Background: Pulmonary hypertension secondary to chronic thromboembolism is a severe and debilitating disease and has been associated with high mortality. Pulmonary thromboendarterectomy is the treatment of choice. Objective: To evaluate the impact of pulmonary thromboendarterectomy on the quality of life of patients with pulmonary hypertension secondary to chronic thromboembolism using the SF-36 Health Survey. Method: The SF-36 Health Survey questionnaire was administered to 13 patients prior to and at least 3 months following thromboendarterectomy. Results: Of the 13 patients studied, 7 were female and 6 were male. Mean age was 45.7 ± 18.3. All were submitted to thromboendarterectomy. After surgery, all SF-36 domains, with the exception of the "mental health" domain, improved. Conclusion: Pulmonary thromboendarterectomy provides significant improvement in patient quality of life.

Keywords: Key words: Hypertension pulmonary. Pulmonary embolism. Endarterectomy/methods. Quality of life.

In view of the fact that the World Health Organization has recommended the use of the mycobacteria growth indicator tube (MGIT) 960 system for the diagnosis of tuberculosis and that there is as yet no evidence regarding the clinical impact of its use in health care systems, we conducted a pragmatic clinical trial to evaluate the clinical performance and cost-effectiveness of the use of MGIT 960 at two health care facilities in the city of Rio de Janeiro, Brazil, where the incidence of tuberculosis is high. Here, we summarize the methodology and preliminary results of the trial. (ISRCTN.org Identifier: ISRCTN79888843 [http://isrctn.org/])

Keywords: Controlled clinical trial; Tuberculosis; Diagnostic tests, routine.

Here, we report high-resolution computed tomography (HRCT) findings in a patient who developed sudden hemoptysis, dyspnea and chest pain after smoking crack cocaine. Chest X-rays showed consolidations, primarily in the upper lobes, and HRCT scans showed ground glass attenuation opacities, consolidations and air-space nodules. A follow-up CT, after drug use discontinuation and administration of corticosteroids, showed partial resolution of pulmonary lesions and the appearance of cavitations. Clinical, imaging and laboratory findings led to a diagnosis of 'crack lung'.

Keywords: Crack cocaine/adverse effects; Cocaine-related disorders; Tomography, X-ray computed; Street drugs/adverse effects;

Pulmonary artery sarcomas are rare, difficult-to-diagnose tumors that frequently mimic chronic pulmonary thromboembolism. We report the cases of two female patients with clinical signs of dyspnea and lung masses associated with pulmonary artery filling defects on chest CT angiography. We performed 18F-fluorodeoxyglucose positron emission tomography, which revealed increased radiotracer uptake in those lesions. Pulmonary artery sarcoma was subsequently confirmed by anatomopathological examination. We emphasize the importance of this type of tomography as a noninvasive method for the diagnosis of these tumors.

Keywords: Positron-emission tomography; Pulmonary artery; Pulmonary embolism; Leiomyosarcoma; Histiocytoma, malignant fibrous.

Abstract Objective: To compare four laboratory methods in the diagnosis of pulmonary tuberculosis. Methods: Respiratory secretion specimens were collected from 160 patients suspected of having pulmonary tuberculosis. Direct testing for Mycobacterium tuberculosis was carried out using Ziehl-Neelsen staining, auramine staining, culture on Löwenstein-Jensen (LJ) medium and polymerase chain reaction (PCR). The strains isolated were identified by means of a radiometric method using p-nitro-alpha-acetylamino-beta-hydroxypropiophenone (NAP) and classical methods. The sensitivity of the methods was compared to the gold standard for the diagnosis of pulmonary tuberculosis, based on clinical, radiological and microbiological criteria. Results: Of the 160 patients, 142 were diagnosed with pulmonary tuberculosis according to the gold standard. The sensitivity of Ziehl-Neelsen staining, auramine staining, culture on LJ medium and PCR was 54.2%, 58.4%, 67.6% and 77.5%, respectively, when compared with the diagnostic criterion adopted. All four methods presented 100% specificity. In the identification of mycobacteria, there was high (96.8%) concordance between PCR and the radiometric method using NAP. The sensitivity of PCR was 50.8% in samples with negative sputum smear microscopy results and 98.8% in those with positive results. The sensitivity of PCR was lower in specimens with negative results in sputum smear microscopy and culture than in those with positive results (25.6% and 99.0%, respectively). Conclusions: We found PCR to be a promising method for the diagnosis of pulmonary tuberculosis, even in paucibacillary specimens. Simultaneous identification and faster results are additional advantages of this method.

Keywords: Tuberculosis, pulmonary/diagnosis; Culture media; Polymerase chain reaction; Sputum/microbiology.