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Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial lung disease that is, by definition, progressive. Progression of IPF is reflected by a decline in lung function, worsening of dyspnea and exercise capacity, and deterioration in health-related quality of life. In the short term, the course of disease for an individual patient is impossible to predict. A period of relative stability in forced vital capacity (FVC) does not mean that FVC will remain stable in the near future. Frequent monitoring using multiple assessments, not limited to pulmonary function tests, is important to evaluate disease progression in individual patients and ensure that patients are offered appropriate care. Optimal management of IPF requires a multidimensional approach, including both pharmacological therapy to slow decline in lung function and supportive care to preserve patients' quality of life.

Lung cancer screening trials provide an opportunity to study the natural history of emphysema by using computed tomography (CT) lung density as a surrogate parameter. In the Danish Lung Cancer Screening Trial, 2,052 participants were included. At screening rounds, smoking habits were recorded and spirometry was performed. CT lung density was measured as the volume-adjusted 15th percentile density (PD15). A mixed effects model was used with former smoking males with,30 pack-yrs and without airflow obstruction (AFO) at entry as a reference group. At study entry, 893 (44%) participants had AFO. For the reference group, PD15 was 72.6 g.L-1 with an annual decline of-0.33 g.L-1. Female sex and current smoking increased PD15 at baseline, 17.3 g.L-1 (p<0.001) and 10 g.L-1 (p<0.001), respectively; and both increased the annual decline in PD15 (female:-0.3 g.L-1; current smoking:-0.4 g.L-1). The presence and severity of AFO was a strong predictor of low PD15 at baseline (Global Initiative for Chronic Obstructive Lung Disease (GOLD) I:-1.4 g.L -1; GOLD II:-6.3 g.L-1; GOLD III:-17 g.L-1) and of increased annual decline in PD15 (GOLD I:-0.2 g.L-1; GOLD II:-0.5 g.L-1; GOLD III:-0.5 g.L-1). Female sex, active smoking and the presence of AFO are associated with accelerated decline in lung density. Copyright

1 augustus 2010, Item does not contain fulltext, OBJECTIVE: We examined the reproducibility of lung nodule volumetry software that offers three different volumetry algorithms. METHODS: In a lung cancer screening trial, 188 baseline nodules >5 mm were identified. Including follow-ups, these nodules formed a study-set of 545 nodules. Nodules were independently double read by two readers using commercially available volumetry software. The software offers readers three different analysing algorithms. We compared the inter-observer variability of nodule volumetry when the readers used the same and different algorithms. RESULTS: Both readers were able to correctly segment and measure 72% of nodules. In 80% of these cases, the readers chose the same algorithm. When readers used the same algorithm, exactly the same volume was measured in 50% of readings and a difference of >25% was observed in 4%. When the readers used different algorithms, 83% of measurements showed a difference of >25%. CONCLUSION: Modern volumetric software failed to correctly segment a high number of screen detected nodules. While choosing a different algorithm can yield better segmentation of a lung nodule, reproducibility of volumetric measurements deteriorates substantially when different algorithms were used. It is crucial even in the same software package to choose identical parameters for follow-up.

Udgivelsesdato: February, We aim at improving quantitative measures of emphysema in computed tomography (CT) images of the lungs. Current standard measures, such as the relative area of emphysema (RA), rely on a single intensity threshold on individual pixels, thus ignoring any interrelations between pixels. Texture analysis allows for a much richer representation that also takes the local structure around pixels into account. This paper presents a texture classification-based system for emphysema quantification in CT images. Measures of emphysema severity are obtained by fusing pixel posterior probabilities output by a classifier. Local binary patterns (LBP) are used as texture features, and joint LBP and intensity histograms are used for characterizing regions of interest (ROIs). Classification is then performed using a k nearest neighbor classifier with a histogram dissimilarity measure as distance. A 95.2% classification accuracy was achieved on a set of 168 manually annotated ROIs, comprising the three classes: normal tissue, centrilobular emphysema, and paraseptal emphysema. The measured emphysema severity was in good agreement with a pulmonary function test (PFT) achieving correlation coefficients of up to |r| = 0.79 in 39 subjects. The results were compared to RA and to a Gaussian filter bank, and the texture-based measures correlated significantly better with PFT than did RA.

Introduction: Inflammation is an important constituent of the pathology of chronic obstructive pulmonary disease (COPD), leading to alveolar destruction and airway remodelling. Objective: The aim of this study was to assess the difference in plasma biomarkers of inflammation between asymptomatic smokers and patients with COPD. Methods: We used commercially available enzyme-linked immunosorbent assay kits to measure the plasma levels of tumour necrosis factor-alpha (TNF-alpha), interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9), monocyte chemotactic protein-1 (MCP-1), tissue inhibitor of metalloproteinase-1 (TIMP-1) and tissue inhibitor of metalloproteinase-2 (TIMP-2) on two occasions with a 2-week interval in patients with COPD (n = 20), asymptomatic smokers (n = 10) and healthy life-long non-smokers (n = 10). The participants were characterised clinically, physiologically and by quantitative computed tomography by measuring the relative area of emphysema below -910 Hounsfield units (RA-910). Results: The results of the biomarker measurements on the two occasions were highly reproducible. Patients with COPD had significantly higher plasma levels of IL-8 (P = 0.004) and significantly lower levels of TIMP-1 (P = 0.02) than smokers and non-smokers. There was no statistically significant difference between the three groups in the level of TNF-alpha, MMP-9, MCP-1 and TIMP-2. The IL-8/TIMP-1 ratio correlated significantly with the degree of airway obstruction measured as forced expiratory volume in 1 second (FEVI) % predicted (r = -0.47, P < 0.01); with the diffusion capacity (r = -0.41, P < 0.01); and with the grade of emphysema measured as RA-910 (r = 0.39, P = 0.01). Conclusion: These findings suggest that the measurement of plasma biomarkers, such as IL-8/TIMP-1, may aid to discriminate patients with COPD from smokers at lower risk of developing COPD Udgivelsesdato: 2008/1