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Rotevatn AØ, Eagan TM, Tangedal S, Husebø GR, Ostridge K, Nielsen R. Gut microbiota in chronic obstructive pulmonary disease varies by CT-verified emphysema status. Eur Clin Respir J 2025; 12:2470499. [PMID: 40017817 PMCID: PMC11866649 DOI: 10.1080/20018525.2025.2470499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2024] [Accepted: 02/17/2025] [Indexed: 03/01/2025] Open
Abstract
Background and aim The association of the gut microbiota to chronic obstructive pulmonary disease (COPD) phenotypes is underexplored. We aimed to compare stool samples from patients with COPD and subjects without COPD and relate findings to emphysema status, exacerbation rate, blood eosinophil levels, symptom score, and lung function. Methods We report findings from a single-centre case-control study with 62 current and former smoking patients with COPD and 49 subjects without COPD. DNA was extracted from stool samples, and the V3V4-region of the bacterial 16S-rRNA gene was sequenced. Emphysema was defined based on thoracic computed tomography (CT thorax) low attenuating areas ≥/<10% at threshold -950 and -910 hounsfield units, respectively. Differential abundance of taxa was evaluated using Analysis of Composition of Microbes with Bias Correction (ANCOM-BC). Beta diversity was compared using a distance-based permanova-test. Results The genus Veillonella was decreased and a genus belonging to class Clostridia was increased in COPD compared with controls without COPD. The composition of microbes (beta diversity) differed in emphysema compared to controls, and 27 genera were differentially abundant in emphysema vs. controls. Nine of these genera belonged to the family Lachnospiraceae. Lung function, blood counts and COPD assessment test score correlated with several genera's relative abundance. Of the genera showing significant correlation to lung function, nine belonged to the family Lachnospiraceae. Conclusion The gut microbiota in COPD differs from that in healthy individuals, even more so in emphysema. In particular, future studies should look into the mechanisms and therapeutic potential of dysbiosis affecting the family Lachnospiraceae.
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Affiliation(s)
- Anders Ørskov Rotevatn
- Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Tomas Mikal Eagan
- Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Solveig Tangedal
- Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Gunnar Reksten Husebø
- Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Kristoffer Ostridge
- Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
- Faculty of Medicine, University of Southampton, Southampton, UK
| | - Rune Nielsen
- Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway
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Wang Y, Chai L, Chen Y, Liu J, Wang Q, Zhang Q, Qiu Y, Li D, Chen H, Shen N, Shi X, Wang J, Xie X, Li M. Quantitative CT parameters correlate with lung function in chronic obstructive pulmonary disease: A systematic review and meta-analysis. Front Surg 2023; 9:1066031. [PMID: 36684267 PMCID: PMC9845891 DOI: 10.3389/fsurg.2022.1066031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 11/14/2022] [Indexed: 01/06/2023] Open
Abstract
Objective This study aimed to analyze the correlation between quantitative computed tomography (CT) parameters and airflow obstruction in patients with COPD. Methods PubMed, Embase, Cochrane and Web of Knowledge were searched by two investigators from inception to July 2022, using a combination of pertinent items to discover articles that investigated the relationship between CT measurements and lung function parameters in patients with COPD. Five reviewers independently extracted data, and evaluated it for quality and bias. The correlation coefficient was calculated, and heterogeneity was explored. The following CT measurements were extracted: percentage of lung attenuation area <-950 Hounsfield Units (HU), mean lung density, percentage of airway wall area, air trapping index, and airway wall thickness. Two airflow obstruction parameters were extracted: forced expiratory volume in the first second as a percentage of prediction (FEV1%pred) and FEV1 divided by forced expiratory volume lung capacity. Results A total of 141 studies (25,214 participants) were identified, which 64 (6,341 participants) were suitable for our meta-analysis. Results from our analysis demonstrated that there was a significant correlation between quantitative CT parameters and lung function. The absolute pooled correlation coefficients ranged from 0.26 (95% CI, 0.18 to 0.33) to 0.70 (95% CI, 0.65 to 0.75) for inspiratory CT and 0.56 (95% CI, 0.51 to 0.60) to 0.74 (95% CI, 0.68 to 0.80) for expiratory CT. Conclusions Results from this analysis demonstrated that quantitative CT parameters are significantly correlated with lung function in patients with COPD. With recent advances in chest CT, we can evaluate morphological features in the lungs that cannot be obtained by other clinical indices, such as pulmonary function tests. Therefore, CT can provide a quantitative method to advance the development and testing of new interventions and therapies for patients with COPD.
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Barrecheguren M, Bals R, Miravitlles M. Clinical approach to the diagnosis and assessment of AATD. Α1-ANTITRYPSIN DEFICIENCY 2019. [DOI: 10.1183/2312508x.10032618] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2025]
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Crossley D, Renton M, Khan M, Low EV, Turner AM. CT densitometry in emphysema: a systematic review of its clinical utility. Int J Chron Obstruct Pulmon Dis 2018; 13:547-563. [PMID: 29445272 PMCID: PMC5808715 DOI: 10.2147/copd.s143066] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The aim of the study was to assess the relationship between computed tomography (CT) densitometry and routine clinical markers in patients with chronic obstructive pulmonary disease (COPD) and alpha-1 anti-trypsin deficiency (AATD). METHODS Multiple databases were searched using a combination of pertinent terms and those articles relating quantitatively measured CT densitometry to clinical outcomes. Studies that used visual scoring only were excluded, as were those measured in expiration only. A thorough review of abstracts and full manuscripts was conducted by 2 reviewers; data extraction and assessment of bias was conducted by 1 reviewer and the 4 reviewers independently assessed for quality. Pooled correlation coefficients were calculated, and heterogeneity was explored. RESULTS A total of 112 studies were identified, 82 being suitable for meta-analysis. The most commonly used density threshold was -950 HU, and a significant association between CT density and all included clinical parameters was demonstrated. There was marked heterogeneity between studies secondary to large variety of disease severity within commonly included cohorts and differences in CT acquisition parameters. CONCLUSION CT density shows a good relationship to clinically relevant parameters; however, study heterogeneity and lack of longitudinal data mean that it is difficult to compare studies or derive a minimal clinically important difference. We recommend that international consensus is reached to standardize CT conduct and analysis in future COPD and AATD studies.
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Affiliation(s)
- Diana Crossley
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
- Correspondence: Diana Crossley, Institute of Inflammation and Ageing, Queen Elizabeth Hospital, Mindelsohn Way, Edgbaston, Birmingham, B15 2TH, UK, Tel +44 121 371 3885, Fax +44 121 371 3203, Email
| | - Mary Renton
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Muhammad Khan
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Emma V Low
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Alice M Turner
- Institute of Applied Health Sciences, University of Birmingham, Birmingham, UK
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Crossley D, Turner A, Subramanian D. Phenotyping emphysema and airways disease: Clinical value of quantitative radiological techniques. World J Respirol 2017; 7:1-16. [DOI: 10.5320/wjr.v7.i1.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 11/23/2016] [Accepted: 01/14/2017] [Indexed: 02/06/2023] Open
Abstract
The pathophysiology of chronic obstructive pulmonary disease (COPD) and Alpha one antitrypsin deficiency is increasingly recognised as complex such that lung function alone is insufficient for early detection, clinical categorisation and dictating management. Quantitative imaging techniques can detect disease earlier and more accurately, and provide an objective tool to help phenotype patients into predominant airways disease or emphysema. Computed tomography provides detailed information relating to structural and anatomical changes seen in COPD, and magnetic resonance imaging/nuclear imaging gives functional and regional information with regards to ventilation and perfusion. It is likely imaging will become part of routine clinical practice, and an understanding of the implications of the data is essential. This review discusses technical and clinical aspects of quantitative imaging in obstructive airways disease.
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Löndahl J, Jakobsson JKF, Broday DM, Aaltonen HL, Wollmer P. Do nanoparticles provide a new opportunity for diagnosis of distal airspace disease? Int J Nanomedicine 2016; 12:41-51. [PMID: 28053522 PMCID: PMC5191892 DOI: 10.2147/ijn.s121369] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
There is a need for efficient techniques to assess abnormalities in the peripheral regions of the lungs, for example, for diagnosis of pulmonary emphysema. Considerable scientific efforts have been directed toward measuring lung morphology by studying recovery of inhaled micron-sized aerosol particles (0.4-1.5 µm). In contrast, it is suggested that the recovery of inhaled airborne nanoparticles may be more useful for diagnosis. The objective of this work is to provide a theoretical background for the use of nanoparticles in measuring lung morphology and to assess their applicability based on a review of the literature. Using nanoparticles for studying distal airspace dimensions is shown to have several advantages over other aerosol-based methods. 1) Nanoparticles deposit almost exclusively by diffusion, which allows a simpler breathing maneuver with minor artifacts from particle losses in the oropharyngeal and upper airways. 2) A higher breathing flow rate can be utilized, making it possible to rapidly inhale from residual volume to total lung capacity (TLC), thereby eliminating the need to determine the TLC before measurement. 3) Recent studies indicate better penetration of nanoparticles than micron-sized particles into poorly ventilated and diseased regions of the lungs; thus, a stronger signal from the abnormal parts is expected. 4) Changes in airspace dimensions have a larger impact on the recovery of nanoparticles. Compared to current diagnostic techniques with high specificity for morphometric changes of the lungs, computed tomography and magnetic resonance imaging with hyperpolarized gases, an aerosol-based method is likely to be less time consuming, considerably cheaper, simpler to use, and easier to interpret (providing a single value rather than an image that has to be analyzed). Compared to diagnosis by carbon monoxide (DL,CO), the uptake of nanoparticles in the lung is not affected by blood flow, hemoglobin concentration or alterations of the alveolar membranes, but relies only on lung morphology.
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Affiliation(s)
- Jakob Löndahl
- Division of Ergonomics and Aerosol Technology (EAT), Department of Design Sciences
- NanoLund, Lund University, Lund, Sweden
| | - Jonas KF Jakobsson
- Division of Ergonomics and Aerosol Technology (EAT), Department of Design Sciences
- NanoLund, Lund University, Lund, Sweden
| | - David M Broday
- Faculty of Civil and Environmental Engineering, Technion, Haifa, Israel
| | - H Laura Aaltonen
- Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Per Wollmer
- Department of Translational Medicine, Lund University, Malmö, Sweden
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Alamidi DF, Morgan AR, Hubbard Cristinacce PL, Nordenmark LH, Hockings PD, Lagerstrand KM, Young SS, Naish JH, Waterton JC, Maguire NC, Olsson LE, Parker GJ. COPD Patients Have Short Lung Magnetic ResonanceT1Relaxation Time. COPD 2015; 13:153-9. [DOI: 10.3109/15412555.2015.1048851] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Sieren JP, Hoffman EA, Fuld MK, Chan KS, Guo J, Newell JD. Sinogram Affirmed Iterative Reconstruction (SAFIRE) versus weighted filtered back projection (WFBP) effects on quantitative measure in the COPDGene 2 test object. Med Phys 2015; 41:091910. [PMID: 25186397 DOI: 10.1118/1.4893498] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Assessing pulmonary emphysema using Quantitative CT of the lung depends on accurate measures of CT density. Sinogram-Affirmed-Iterative-Reconstruction (SAFIRE) is a new approach for reconstructing CT data acquired at significantly lower doses. However, quantitative effects of this method remain unexplored. The authors investigated the effects on the median values of materials in the COPDGene2 test-object as a function of the reconstruction method [weighted filtered back projection (WFBP) versus SAFIRE], test-object size, dose, and material composition using a Siemens SOMATOM Definition FLASH CT scanner. METHODS The COPDGene2 test-object contains eight materials; acrylic, water, four foams (20 lb, 12 lb, lung-equivalent, and 4 lb emphysema-equivalent), internal and external-air. The test-object was scanned with three different outer ring sizes, simulating three different body habitus. There is an average size (36 cm) Ring A, large size (40 cm) Ring B, and small size Ring C (30 cm). The CT protocol used 120 kVp, 0.5 s rotation, 1.0 pitch, and a 0.6 slice collimation with progressively decreasing x-ray exposure values, 11.94-0.74 mGy. With a thorax length of 30 cm, the corresponding effective doses would be 5.01-0.31 mSv. The effects of using SAFIRE versus WFBP were assessed using a two tailed t-test for each ring size, material, and dose. Multivariable linear regression was used to evaluate the relative effects of ring size, material composition, dose, and reconstruction method on the measured median value in HU. RESULTS SAFIRE versus WFBP, at the largest ring size and two lowest doses there was a significant difference in median values of 4 lb-foam, p<0.01. Using the smallest ring size at the lowest dose level there was a significant difference in the median value of 4 lb-foam, but the effect size was small, 1 HU. There is a significant difference in median values of both internal and external air using both the small and medium size rings at the three lowest dose levels, p<0.05. There are significant differences noted at both high and low dose levels when using the large ring size in the median values of internal and external air when, p<0.05. These effects on 4 lb-foam, inside and outside air are shown to be in part due to truncation effects on the median value since the lowest HU value in the CT scale used is -1024 HU. Multivariable linear regression results demonstrated significant effects on the measured material median value and standard deviation due to ring size, material composition, dose level, and reconstruction method, p<0.05. CONCLUSIONS The authors have shown that there is no significant effect on the median values obtained when using WFBP versus SAFIRE in materials with CT density between 120 and -856 HU using three different test-object sizes and CT doses that vary from 11.94 to 0.74 mGy. The authors have demonstrated there are significant effects on median values obtained when using WFBP versus SAFIRE in materials with CT density values between -937 and -1000 HU depending on the ring size and dose used. As expected, there is considerable reduction in image noise (lower standard deviation) using SAFIRE versus WFBP with all ring sizes, doses, and materials in the COPDGene2 test-object.
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Affiliation(s)
- J P Sieren
- Department of Radiology, University of Iowa, Iowa City, Iowa 52242
| | - E A Hoffman
- Department of Radiology, University of Iowa, Iowa City, Iowa 52242; Department of Medicine, University of Iowa, Iowa City, Iowa 52242; and Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa 52242
| | - M K Fuld
- Siemens Medical Solutions Inc., Malvern, Pennsylvania 19355
| | - K S Chan
- Department of Statistics and Actuarial Science, University of Iowa, Iowa City, Iowa 52242
| | - J Guo
- Department of Radiology, University of Iowa, Iowa City, Iowa 52242
| | - J D Newell
- Department of Radiology, University of Iowa, Iowa City, Iowa 52242 and Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa 52242
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Thomsen LH, Shaker SB, Dirksen A, Pedersen JH, Tal-Singer R, Bakke P, Vestbo J. Correlation Between Emphysema and Lung Function in Healthy Smokers and Smokers With COPD. CHRONIC OBSTRUCTIVE PULMONARY DISEASES-JOURNAL OF THE COPD FOUNDATION 2015; 2:204-213. [PMID: 28848844 DOI: 10.15326/jcopdf.2.3.2014.0154] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Background: Emphysema is an important component of COPD; however, in previous studies of the correlation between airflow limitation (AFL) and computed tomography (CT) lung density as a surrogate for emphysema has varied. We hypothesised a good correlation between lung function (forced expiratory volume in first second [FEV1]) and emphysema (15th percentile density [PD15]) and that this correlation also exists between loss of lung tissue and decline in lung function even within the time frame of longitudinal studies of relatively short duration. Methods: We combined 2 large longitudinal studies (the Danish Lung Cancer Screening Trial [DLCST] and the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints [ECLIPSE]) of smokers or former smokers, with a wide range of AFL and CT lung density, and analysed data from 2148 participants who did not change smoking habits and who had at least 2 CT scans and 2 FEV1 measurements at least 3 years apart. Results: Baseline correlation between FEV1 and PD15 was high (r=0.716, 95% confidence interval [CI]: 0.694-0.736, p<0.001) indicating that at least half of the variation in FEV1 can be explained by variation in CT lung density. Correlation between the decline in FEV1 and progression of PD15 was considerably weaker (r= 0.081, 95% CI: 0.038-0.122, p<0.001). Conclusions: Correlation is very high between lung density and lung function in a broad spectrum of smokers and ex-smokers. In contrast, the temporal associations (slopes) are weakly correlated, probably due to uncertainty in the estimation of slopes within a time frame of 3-4 years.
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Affiliation(s)
- Laura H Thomsen
- Department of Respiratory Medicine, Gentofte Hospital, University of Copenhagen, Denmark
| | - Saher B Shaker
- Department of Respiratory Medicine, Gentofte Hospital, University of Copenhagen, Denmark
| | - Asger Dirksen
- Department of Respiratory Medicine, Gentofte Hospital, University of Copenhagen, Denmark
| | - Jesper H Pedersen
- Department of Cardiothoracic Surgery, University of Copenhagen, Denmark
| | | | - Per Bakke
- Department of Clinical Science, University of Bergen, and Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
| | - Jørgen Vestbo
- Department of Respiratory Medicine, Gentofte Hospital, University of Copenhagen, Denmark.,Respiratory and Allergy Research Group, Manchester Academic Health Science Centre, University Hospital South Manchester; NHS Foundation Trust, Manchester, United Kingdom
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Bandyopadhyay S, Henne E, Gupta A, Barry R, Snell G, Strange C, Herth FJF. Segmental approach to lung volume reduction therapy for emphysema patients. ACTA ACUST UNITED AC 2014; 89:76-81. [PMID: 25500669 DOI: 10.1159/000369036] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 09/22/2014] [Indexed: 11/19/2022]
Abstract
Emphysema is often distributed heterogeneously throughout the lungs, even at the segmental level. It is important for interventional lung volume reduction therapies to target and treat the most diseased regions of the lung while preserving the less diseased functional regions. Identification and determination of the severity of emphysema can be done using the various quantification measures reviewed in this article. However, all of these measures are similar in what they quantify and are equally good indicators of emphysema. The tissue/air ratio was chosen for our purposes. Software capable of quantifying emphysema severity at the segmental level exists, and can be utilized to identify the most diseased segments while following anatomical boundaries. The segmental heterogeneity index is a new measure being introduced to help quantify differences in emphysema severity at the segmental level. The goal of segmental targeting is to improve efficacy and safety outcomes of vapor ablation patients. The Sequential Staged Treatment of Emphysema with Upper Lobe Predominance (STEP-UP, NCT01719263) trial is currently enrolling patients with upper lobe heterogeneous emphysema using these techniques.
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Xie X, de Jong PA, Oudkerk M, Wang Y, Ten Hacken NHT, Miao J, Zhang G, de Bock GH, Vliegenthart R. Morphological measurements in computed tomography correlate with airflow obstruction in chronic obstructive pulmonary disease: systematic review and meta-analysis. Eur Radiol 2012; 22:2085-93. [PMID: 22699870 PMCID: PMC3431473 DOI: 10.1007/s00330-012-2480-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 03/20/2012] [Accepted: 03/26/2012] [Indexed: 01/08/2023]
Abstract
Objectives To determine the correlation between CT measurements of emphysema or peripheral airways and airflow obstruction in chronic obstructive pulmonary disease (COPD). Methods PubMed, Embase and Web of Knowledge were searched from 1976 to 2011. Two reviewers independently screened 1,763 citations to identify articles that correlated CT measurements to airflow obstruction parameters of the pulmonary function test in COPD patients, rated study quality and extracted information. Three CT measurements were accessed: lung attenuation area percentage < -950 Hounsfield units, mean lung density and airway wall area percentage. Two airflow obstruction parameters were accessed: forced expiratory volume in the first second as percentage from predicted (FEV1 %pred) and FEV1 divided by the forced volume vital capacity. Results Seventy-nine articles (9,559 participants) were included in the systematic review, demonstrating different methodologies, measurements and CT airflow obstruction correlations. There were 15 high-quality articles (2,095 participants) in the meta-analysis. The absolute pooled correlation coefficients ranged from 0.48 (95 % CI, 0.40 to 0.54) to 0.65 (0.58 to 0.71) for inspiratory CT and 0.64 (0.53 to 0.72) to 0.73 (0.63 to 0.80) for expiratory CT. Conclusions CT measurements of emphysema or peripheral airways are significantly related to airflow obstruction in COPD patients. CT provides a morphological method to investigate airway obstruction in COPD. Key Points • Computed tomography is widely performed in patients with chronic obstructive pulmonary disease (COPD) • CT provides quantitative morphological methods to investigate airflow obstruction in COPD • CT measurements correlate significantly with the degree of airflow obstruction in COPD • Expiratory CT measurements correlate more strongly with airflow obstruction than inspiratory CT • Low-dose CT decreases the radiation dose for diagnosis and quantitative emphysema evaluation Electronic supplementary material The online version of this article (doi:10.1007/s00330-012-2480-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xueqian Xie
- Center for Medical Imaging-North East Netherlands (CMI-NEN), Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30.001, 9700, RB, Groningen, The Netherlands
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Abstract
Chronic obstructive pulmonary disease (COPD) is divided into pulmonary emphysema and chronic bronchitis (CB). Emphysema is defined patho-anatomically as "permanent enlargement of airspaces distal to the terminal bronchiole, accompanied by the destruction of their walls, and without obvious fibrosis" (1). These lesions are readily identified and quantitated using computed tomography (CT), whereas the accompanying hyperinflation is best detected on plain chest X-ray, especially in advanced disease. The diagnosis of CB is clinical and relies on the presence of productive cough for 3 months in 2 or more successive years. The pathological changes of mucosal inflammation and bronchial wall thickening have been more difficult to identify with available imaging techniques. However, recent studies using Multi-detector row CT (MDCT) reported more reproducible assessment of air wall thickening.
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Affiliation(s)
- Saher B Shaker
- Department of Respiratory Medicine, Gentofte University Hospital, Hellerup, Denmark.
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Mata JF, Altes TA, Cai J, Ruppert K, Mitzner W, Hagspiel KD, Patel B, Salerno M, Brookeman JR, de Lange EE, Tobias WA, Wang HTJ, Cates GD, Mugler JP. Evaluation of emphysema severity and progression in a rabbit model: comparison of hyperpolarized 3He and 129Xe diffusion MRI with lung morphometry. J Appl Physiol (1985) 2006; 102:1273-80. [PMID: 17110518 DOI: 10.1152/japplphysiol.00418.2006] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The apparent diffusion coefficients (ADCs) of hyperpolarized (3)He and (129)Xe gases were measured in the lungs of rabbits with elastase-induced emphysema and correlated against the mean chord length from lung histology. In vivo measurements were performed at baseline and 2, 4, 6, and 8 wk after instillation of elastase (mild and moderate emphysema groups) or saline (control group). ADCs were determined from acquisitions that used two b values. To investigate the effect of b value on the results, b-value pairs of 0 and 1.6 s/cm(2) and 0 and 4.0 s/cm(2) were used for (3)He, and b-value pairs of 0 and 5.0 s/cm(2) and 0 and 10.0 s/cm(2) were used for (129)Xe. At 8 wk after instillation, the rabbits were euthanized, and the lungs were analyzed histologically and morphometrically. ADCs for the rabbits in the control group did not change significantly from baseline to week 8, whereas ADCs for the rabbits in the emphysema groups increased significantly (P < 0.05) for all gas and b-value combinations except (129)Xe with the b-value pair of 0 and 5.0 s/cm(2). The largest percent change in mean ADC from baseline to week 8 (15.3%) occurred with (3)He and the b-value pair of 0 and 1.6 s/cm(2) for rabbits in the moderate emphysema group. ADCs (all b values) were strongly correlated (r = 0.62-0.80, P < 0.001) with mean chord lengths from histology. These results further support the ability of diffusion-weighted MRI with hyperpolarized gases to detect regional and global structural changes of emphysema within the lung.
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Affiliation(s)
- Jaime F Mata
- Dept. of Radiology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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