832 research outputs found
Monitoring of Cystic Fibrosis Lung Disease Using Computed Tomography
For clinical management of cystic fibrosis (CF) lung disease
to be effective, onset and worsening of lung abnormalities should be closely
monitored. Pulmonary function tests (PFTs) are currently the gold standard to
monitor CF lung disease. Lung structure can be more sensitively monitored using
computed tomography (CT) rather than chest radiography. Firstly, we compared in
two pediatric cohorts the sensitivities of CT and PFTs to detect onset and
worsening of CF lung disease. We showed that five published CT scoring systems
are comparable and have good intra- and interobserver agreement. Secondly, we
showed that CT scoring systems and quantitative CT-measurements of airway wall
thickening and bronchiectasis are more sensitive to detect the start and
worsening of CF lung disease than are PFTs. Bronchiectasis-score worsened most
in children and the worsening remained undetected by the PFTs and the
quantitative measurements. Quantitative CT-measurements of air!
way wall thickening worsened significantly, whereas PFTs and airway wall
thickness measured by scoring remained unchanged. Thirdly, we developed a
computational model to study radiation risks associated with CT scanning in CF.
Risks from lifelong biennial CT scanning in CF were found to be acceptably low
given the currently reduced life expectancy. Finally we provided normal
CT-values of lung parenchyma and airway wall and lumen that can be used to study
lung growth aberrations due to CF. Our data support routine CT scanning to
monitor CF lung disease. In addition, bronchiectasis-score and quantitatively
measured airway wall thickening may be useful surrogate endpoints for clinical
trials in CF
Automatic calcium scoring in low-dose chest CT using deep neural networks with dilated convolutions
Heavy smokers undergoing screening with low-dose chest CT are affected by
cardiovascular disease as much as by lung cancer. Low-dose chest CT scans
acquired in screening enable quantification of atherosclerotic calcifications
and thus enable identification of subjects at increased cardiovascular risk.
This paper presents a method for automatic detection of coronary artery,
thoracic aorta and cardiac valve calcifications in low-dose chest CT using two
consecutive convolutional neural networks. The first network identifies and
labels potential calcifications according to their anatomical location and the
second network identifies true calcifications among the detected candidates.
This method was trained and evaluated on a set of 1744 CT scans from the
National Lung Screening Trial. To determine whether any reconstruction or only
images reconstructed with soft tissue filters can be used for calcification
detection, we evaluated the method on soft and medium/sharp filter
reconstructions separately. On soft filter reconstructions, the method achieved
F1 scores of 0.89, 0.89, 0.67, and 0.55 for coronary artery, thoracic aorta,
aortic valve and mitral valve calcifications, respectively. On sharp filter
reconstructions, the F1 scores were 0.84, 0.81, 0.64, and 0.66, respectively.
Linearly weighted kappa coefficients for risk category assignment based on per
subject coronary artery calcium were 0.91 and 0.90 for soft and sharp filter
reconstructions, respectively. These results demonstrate that the presented
method enables reliable automatic cardiovascular risk assessment in all
low-dose chest CT scans acquired for lung cancer screening
Regulatory Properties of Magnesium-dependent Guanylate Cyclase in Dictyostelium discoideum Membranes
Normal mediastinal and hilar lymph nodes in children on multi-detector row chest computed tomography
Patterns, Predictors, and Prognostic Value of Skeletal Muscle Mass Loss in Patients with Locally Advanced Head and Neck Cancer Undergoing Cisplatin-Based Chemoradiotherapy
Low skeletal muscle mass (SMM) is associated with toxicities and decreased survival in head and neck cancer (HNC). Chemoradiotherapy (CRT) may exaggerate loss of SMM. We investigated the changes in SMM, their predictors, and prognostic impact of SMM in patients treated with CRT between 2012 and 2018. Skeletal muscle area (SMA) segmentation was performed on pre- and post-CRT imaging. Observed changes in SMM were categorized into: (I) Stable, (II) moderate gain (III), moderate loss, (IV) large gain, and (V) large loss. In total, 235 HNC patients were included, of which 39% had stable SMM, 55% moderate loss, 13% moderate gain, 0.4% large loss, and 0.4% large gain of SMM. After CRT, SMA decreased compared to pre-CRT (31.6 cm(2) versus 33.3 cm(2), p = 30 kg/m(2) (OR 3.6, 95% CI 1.4-9.3, p < 0.01). Low SMM at diagnosis (HR 2.1; 95% CI 1.1-4.1, p = 0.03) and an HPV-positive oropharyngeal tumor (HR 0.1; 95% CI 0.01-0.9, p = 0.04) were prognostic for overall survival. Changes in SMM were not prognostic for survival. Loss of SMM is highly prevalent after CRT and a high BMI before treatment may aid in identifying patients at risk
The Incidence of Trilateral Retinoblastoma : A Systematic Review and Meta-Analysis
PURPOSE: To estimate the incidence of trilateral retinoblastoma in patients with retinoblastoma. " DESIGN: Systematic review and meta-analysis. METHODS: We searched Medline and Embase for scientific literature published between January 1966 and July 2015 that assessed trilateral retinoblastoma incidence. We used a random-effects model for the statistical analyses. " RESULTS: We included 23 retinoblastoma cohorts from 26 studies. For patients with bilateral retinoblastoma the unadjusted chance of developing trilateral retinoblastoma across all cohorts was 5.3% (95% confidence interval [CI]: 3.3%-7.7%); the chance of pineal trilateral retinoblastoma was 4.2% (95% CI: 2.6%-6.2%) and the chance of nonpineal trilateral retinoblastoma was 0.8% (95% CI: 0.4%-1.3%). In patients with hereditary retinoblastoma (all bilateral cases, and the unilateral cases with a family history or germline RB1 mutation) we found a trilateral retinoblastoma incidence of 4.1% (95% CI: 1.9%-7.1%) and a pineal trilateral retinoblastoma incidence of 3.7% (95% CI: 1.8%-6.2%). To reduce the risk of overestimation bias we restricted analysis to retinoblastoma cohorts with a minimum size of 100 patients, resulting in adjusted incidences of 3.8% (95% CI: 2.4%-5.4%), 2.9% (95% CI: 1.9%-4.2%), and 0.7% (95% CI: 0.3%-1.2%) for any, pineal, and nonpineal trilateral retinoblastoma, respectively, among patients with bilateral retinoblastoma. Among hereditary retinoblastoma we found an adjusted trilateral retinoblastoma incidence of 3.5% (95% CI: 1.2%-6.7%) and a pineal trilateral retinoblastoma incidence of 3.2% (95% CI: 1.4%-5.6%). CONCLUSION: The estimated incidence of trilateral retinoblastoma is lower than what is reported in previous literature, especially after exclusion of small cohorts that were subject to overestimation bias in this context. (C) 2015 by Elsevier Inc. All rights reserved.)Peer reviewe
Progressive damage on high resolution computed tomography despite stable lung function in cystic fibrosis
For effective clinical management of cystic fibrosis (CF) lung disease it
is important to closely monitor the start and progression of lung damage.
The aim of this study was to investigate the ability of high-resolution
computed tomography (HRCT) scoring systems and pulmonary function tests
(PFT) to detect changes in lung disease. CF children (n=48) had two H
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