A retrospective analysis of transudative pleural effusion due to fibrosing mediastinitis.

BACKGROUND: Pleural effusion caused by fibrosing mediastinitis is rarely reported. This study aimed to summarize the clinical manifestations, diagnosis and treatment of transudative pleural effusion due to fibrosing mediastinitis. METHODS: Medical records and follow-up data of 7 patients with transudative pleural effusion due to fibrosing mediastinitis in Beijing Chaoyang Hospital between May 2014 and Feb 2018 were retrospectively analyzed. RESULTS: These patients included 4 males and 3 females, with an average age of (64 ± 9) years. There were 3 left-sided effusions, 2 right-sided effusions and 2 bilateral effusions. Previous or latent tuberculosis was found in 6 patients. Pulmonary hypertension was indicated by echocardiography in all the 7 patients. Computed tomography pulmonary angiography (CTPA) of all the 7 cases showed increased soft tissue images visible in the mediastinum and bilateral hilus, different degrees of stenosis or occlusion in the pulmonary artery and pulmonary vein. In addition, 4 cases were found of right middle lobe atelectasis with a mediastinal window setting. There was interstitial pulmonary edema on the side of pleural effusion with a lung window setting. All the 7 patients were treated with intermittent drainage of pleural effusion combined with diuretic therapy. Five patients were treated with antituberculosis therapy. Up to now, two patients died of right heart failure and respiratory failure after 2 and 16 months respectively; The remaining 5 patients were still in follow up. CONCLUSION: Fibrosing mediastinitis can lead to pulmonary vein stenosis or occlusion, and thus cause transudative pleural effusion, which can be detected by CTPA. Pulmonary hypertension, long time of cough, and a history of tuberculosis are common in these patients. The common therapy is intermittent drainage of pleural effusion combined with diuretic therapy.

Delayed contrast-enhanced magnetic resonance imaging enables detection of pulmonary artery lesions in Takayasu's arteritis.

Background: Delayed contrast-enhanced magnetic resonance imaging (DE-MRI) is a useful technique to identify arterial wall inflammation. The aim of this study was to explore the value of DE-MRI in the evaluation of pulmonary artery (PA) lesions in Takayasu's arteritis (TAK) compared with 18F-fuorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Methods: Patients with TAK were recruited for this prospective, observational study. Imaging and clinical assessments were performed concurrently. Only thoracic arteries were evaluated, and they were divided into 18 segments per person. All arterial lesions were evaluated using both PET/CT and DE-MRI. Correlations between both methods were assessed in the PA and thoracic aorta. A receiver operating characteristic (ROC) curve was used to analyze the value of imaging features in detecting disease activity based on National Institutes of Health (NIH) criteria. Results: A total of 24 patients contributed 432 arterial segments. Using PET/CT, correlations between arterial wall DE, thickening, and edema in the PA were 84.52%, 67.92%, and 58.33%, respectively, with Cohen's kappa =0.69, 0.30, and 0.13, respectively; for the thoracic aorta, the values were 86.38%, 80.00%, and 75.92%, respectively, with Cohen's kappa =0.71, 0.52, and 0.372, respectively. There was a significant difference in the incidence of wall DE between the PA and thoracic aorta in patients with clinically active TAK (χ2=6.85, P=0.009). DE-MRI presented a higher area under the curve [area under the curve (AUC); 0.729, P=0.047] than wall thickening and edema in the detection of TAK activity. The wall DE combined with erythrocyte sedimentation rate (ESR) showed improved efficiency (AUC: 0.858, P=0.003). Conclusions: DE-MRI displays appreciable correlations with PET/CT findings and allows for the detection of PA inflammation in patients with TAK; it shows higher values in the thoracic aorta than in the PA. The combination of wall DE and ESR can improve the efficiency of assessing disease status.

Clinical Features and Outcomes of Pulmonary Artery Sarcoma.

OBJECTIVES: A retrospective cohort study was designed to describe the clinical features and outcomes of pulmonary artery sarcoma (PAS). METHODS: Twenty-two (22) consecutive patients diagnosed with PAS by pathological examination were enrolled and followed up until they died or until January 2020. The medical records were retrospectively reviewed to evaluate the clinical characteristics, image findings, and outcomes. RESULTS: 1) Twenty-one (21, 95.5%) patients were firstly misdiagnosed. Dyspnoea was the most common presenting symptom (19 of 22, 86.4%). 2) Filling defects in the right pulmonary artery were seen in 17 patients (77.3%) with computed tomography pulmonary angiography or magnetic resonance pulmonary angiography. Among those patients, 14 underwent positron emission tomography-computed tomography detection and 13 (92.9%) were found to have increased uptake value in the pulmonary artery. 3) The median survival (from diagnosis to death or January 2020) of the total series was 11.6 months (range, 0.7-68.5 months). The estimated cumulative survival rates at 1, 2, and 3 years were 52.6%, 32.8%, and 19.7%, respectively. Patients who received surgery and/or chemo-radiotherapy treatment had a better survival rate compared with patients without treatment (the estimated cumulative survival rates at 1, 2, and 3 years were 60.3%, 39.1%, and 29.3%, respectively, vs 33.3%, 16.6%, and 0, accordingly) and better survival time (median survival 17.02 vs 3.16 months, respectively) (p=0.025). CONCLUSIONS: Pulmonary artery sarcoma is easily misdiagnosed, as the symptoms and routine image detection are nonspecific. Positron emission tomography-computed tomography may be helpful in diagnosis. Surgery and/or chemo-radiotherapy offer a chance for better outcomes.

Enhanced water splitting performance of GaN nanowires fabricated using anode aluminum oxide templates.

Highly ordered GaN nanowires were fabricated using an anodic aluminum oxide (AAO) template. Compared to planar GaN, the GaN nanowires significantly increased the light absorption, and the saturated photocurrent increased by a factor of 5 from 0.075 to 0.38 mA cm-2. The photocurrent increase with the GaN nanowires is not only due to their increased surface to volume ratio and reduction in the distance for photo-generated carriers to reach the electrolyte, but also the built-in electric field, which mainly contribute to the enhancement in their water splitting ability. The GaN nanowires can lead to band bending due to their surface states and the formation of a polarized electric field to accelerate the separation of photo-generated carriers. We also established a theoretic model to simulate the band bending in the nanowires. The results showed that when the nanowire diameters are equal or bigger than the full width of depletion region, the nanowires have the maximum electric field, which improves their water splitting performance significantly. These results provide a cost-effective way for highly efficient water splitting.

Differential Diagnosis of Pulmonary Artery Sarcoma and Central Chronic Pulmonary Thromboembolism Using CT and MR Images.

BACKGROUND: Clinical and imaging manifestations are similar in pulmonary artery sarcomas (PAS) and thromboembolic diseases, especially central chronic pulmonary thromboembolism (CPTE). The feasibility of utilising clinical imaging tools such as computed tomography (CT) and magnetic resonance imaging (MRI) for differential diagnosis of PAS and CPTE has not been fully explored, especially MRI. METHODS: Patients with PAS (n=18) and central CPTE (n=20) treated at our hospital between January 2013 and September 2016 were identified retrospectively. Computed tomography and MRI findings of pulmonary artery (PA) filling defects including the location, the involvement of pulmonary artery, morphology, signal intensities and enhancement in MRI, calcification, sizes of right atrium and ventricle, inner diameters of the pulmonary artery trunk and branches, and mediastinal collateral circulation in both groups were examined, and differences were analysed by Fisher exact test and independent sample t-test. RESULTS: Compared to those of central CPTE, PAS lesions were in full shape or expansive growth (p<0.001), and the proximal end of the tumours was often bulging or lobulated (p<0.001). These lesions were aneurysm- or grape-like distally (p<0.01) with inhomogeneous enhancement (p<0.001). The MRI contrast enhancement pattern of PAS lesions were cloudy with inhomogeneous delayed enhancement and the time-density curves for some of the lesions increased gradually. CONCLUSION: Computed tomographic and MR imaging manifestations may resemble PAS and central CPTE; however, some manifestations still have great value for the differential diagnosis of these two conditions, specifically the morphology and MRI enhancement patterns.

Multiparametric MRI in differentiating pulmonary artery sarcoma and pulmonary thromboembolism: a preliminary experience.

PURPOSE: We aimed to define multiparametric magnetic resonance imaging (MRI) findings to differentiate between pulmonary artery sarcoma (PAS) and pulmonary thromboembolism (PTE). METHODS: Eleven patients with suspected PTE were prospectively included to undergo pulmonary MRI before surgery or biopsy. MRI protocol included an unenhanced sequence, diffusion-weighted imaging (DWI, b=800 s/mm2) and a dynamic contrast-enhanced sequence. Morphologic characteristics including distribution, filling defect, and intensity were observed on T1-, T2-, and fat-suppressed T2-weighted imaging, DWI, and contrast-enhanced MRI. Apparent diffusion coefficient (ADC) values were calculated. RESULTS: Six patients were pathologically diagnosed as PAS and the other five as chronic PTE. There were no significant differences in age, gender, presenting symptoms, D-dimer, and N-terminal pro-brain natriuretic peptide between the two groups (P > 0.05). Among MRI findings that were tested for their ability to diagnose PAS, area under the curve (AUC) was significantly higher than 0.5 for main pulmonary artery involvement (AUC, 0.83±0.13; P = 0.011), hyperintensity on fat-suppressed T2-weighted imaging (AUC, 0.82±0.14; P = 0.025), hyperintensity on DWI (AUC, 0.88±0.12; P = 0.002), contrast enhancement (AUC, 0.92±0.10; P < 0.001) and pleural effusion (AUC, 0.82±0.14; P = 0.025). Moreover, grape-like appearance in distal pulmonary artery and cardiac invasion had 100% specificity for diagnosis of PAS. However, ADC value of PAS was not significantly different than that of chronic PTE (U, 12.00; P = 0.584). CONCLUSION: Hyperintense filling defect in main pulmonary artery on fat-suppressed T2-weighted imaging and DWI and contrast enhancement may help to discriminate PAS from PTE.

[The clinical application of electron beam tomography in the diagnosis of pulmonary thromboembolism].

OBJECTIVE: To evaluate the clinical significance of electron beam computerized tomography (EBCT) in the diagnosis and differential diagnosis of pulmonary thromboembolism (PTE). METHODS: EBCT was performed before March 2004 in 114 consecutive patients with clinically suspected pulmonary vascular diseases, including 76 patients with PTE, 29 with pulmonary arteritis, 5 with primary pulmonary arterial tumor, and 4 with pulmonary arterial invasion by lung or mediastinal carcinoma. EBCT was performed using Imatron C-150 scanner with enhanced continuum volume scan (CVS). The slice thickness was 3 mm with scanning time of 0.1 s. The total amount of contrast media (Omnipaque-300) used was 50-100 ml, with flow rates of 3.0-4.0 ml/s and a delay time of 14-25 s. RESULTS: Deep venous thrombosis (DVT) was confirmed in 58 (76.3%) of the 76 patients with PTE (52 men and 24 women), 8 (10.6%) of them without apparent causes. Of the 2 356 pulmonary arterial branches observed in the 76 cases, 1,668 branches (70.8%) showed signs of PTE, with 545 branches (32.7%) of the central pulmonary arteries and 1 123 branches (67.3%) of the peripheral pulmonary arteries. Central type filling defect, such as the "railway sign" or the "drifting sign", was specific for acute thrombosis. Thrombus calcification was a specific sign of chronic PTE. Indirect signs of PTE included mosaic signs, enlargement of the right ventricle and atrium, pulmonary artery enlargement, pulmonary infarction, pericardial and/or pleural effusion, pulmonary atelectasis and pulmonary consolidation. Pulmonary arteritis (including pulmonary arterial involvement in Takayasu arteritis) was diagnosed by EBCT in 27 (93.1%) of the 29 patients, in which the diagnosis was confirmed by pulmonary angiography in 16, and clinically in 13 Patients. Of the 5 patients with primary pulmonary arterial tumor confirmed by pathology, 1 was misdiagnosed by EBCT. Of the 4 patients with pulmonary arterial involvement by lung or mediastinal carcinoma, 3 were confirmed by surgery and 1 by pulmonary angiography. CONCLUSIONS: DVT and PTE are different manifestations of one disease. The diagnostic strategy aims to detect thrombosis in the pulmonary arteries and in the deep veins of the lower limbs at the same time. EBCT is an effective and non-invasive examination in the diagnosis and differential diagnosis of PTE. By EBCT, acute and chronic thrombi can be initially differentiated, and changes in lung parenchyma, mediastinum, and the pulmonary and systemic arterial walls can be observed, and therefore more valuable radiological information can be collected for clinical decision-making.