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Combs MP, Luth JE, Falkowski NR, Wheeler DS, Walker NM, Erb-Downward JR, Wakeam E, Sjoding MW, Dunlap DG, Admon AJ, Dickson RP, Lama VN. The Lung Microbiome Predicts Mortality and Response to Azithromycin in Lung Transplant Recipients with Chronic Rejection. Am J Respir Crit Care Med 2024; 209:1360-1375. [PMID: 38271553 PMCID: PMC11146567 DOI: 10.1164/rccm.202308-1326oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 01/24/2024] [Indexed: 01/27/2024] Open
Abstract
Rationale: Chronic lung allograft dysfunction (CLAD) is the leading cause of death after lung transplant, and azithromycin has variable efficacy in CLAD. The lung microbiome is a risk factor for developing CLAD, but the relationship between lung dysbiosis, pulmonary inflammation, and allograft dysfunction remains poorly understood. Whether lung microbiota predict outcomes or modify treatment response after CLAD is unknown. Objectives: To determine whether lung microbiota predict post-CLAD outcomes and clinical response to azithromycin. Methods: Retrospective cohort study using acellular BAL fluid prospectively collected from recipients of lung transplant within 90 days of CLAD onset. Lung microbiota were characterized using 16S rRNA gene sequencing and droplet digital PCR. In two additional cohorts, causal relationships of dysbiosis and inflammation were evaluated by comparing lung microbiota with CLAD-associated cytokines and measuring ex vivo P. aeruginosa growth in sterilized BAL fluid. Measurements and Main Results: Patients with higher bacterial burden had shorter post-CLAD survival, independent of CLAD phenotype, azithromycin treatment, and relevant covariates. Azithromycin treatment improved survival in patients with high bacterial burden but had negligible impact on patients with low or moderate burden. Lung bacterial burden was positively associated with CLAD-associated cytokines, and ex vivo growth of P. aeruginosa was augmented in BAL fluid from transplant recipients with CLAD. Conclusions: In recipients of lung transplants with chronic rejection, increased lung bacterial burden is an independent risk factor for mortality and predicts clinical response to azithromycin. Lung bacterial dysbiosis is associated with alveolar inflammation and may be promoted by underlying lung allograft dysfunction.
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Affiliation(s)
| | | | | | | | | | | | - Elliot Wakeam
- Division of Thoracic Surgery, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Michael W. Sjoding
- Division of Pulmonary and Critical Care and
- Weil Institute for Critical Care Research and Innovation, Ann Arbor, Michigan
| | - Daniel G. Dunlap
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Andrew J. Admon
- Division of Pulmonary and Critical Care and
- Weil Institute for Critical Care Research and Innovation, Ann Arbor, Michigan
| | - Robert P. Dickson
- Division of Pulmonary and Critical Care and
- Weil Institute for Critical Care Research and Innovation, Ann Arbor, Michigan
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan; and
| | - Vibha N. Lama
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University, Atlanta, Georgia
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2
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Combs MP, Belloli EA, Gargurevich N, Flaherty KR, Murray S, Galbán CJ, Lama VN. Results from randomized trial of pirfenidone in patients with chronic rejection (STOP-CLAD study). J Heart Lung Transplant 2024:S1053-2498(24)01684-X. [PMID: 38796045 DOI: 10.1016/j.healun.2024.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 05/10/2024] [Accepted: 05/19/2024] [Indexed: 05/28/2024] Open
Abstract
BACKGROUND Chronic lung allograft dysfunction (CLAD) is the leading long-term cause of poor outcomes after transplant and manifests by fibrotic remodeling of small airways and/or pleuroparenchymal fibroelastosis. This study evaluated the effect of pirfenidone on quantitative radiographic and pulmonary function assessment in patients with CLAD. METHODS We performed a single-center, 6-month, randomized, placebo-controlled trial of pirfenidone in patients with CLAD. Randomization was stratified by CLAD phenotype. The primary outcome for this study was change in radiographic assessment of small airways disease, quantified as percentage of lung volume using parametric response mapping analysis of computed tomography scans (PRMfSAD); secondary outcomes included change in forced expiratory volume in 1 second (FEV1), change in forced vital capacity (FVC), and change in radiographic quantification of parenchymal disease (PRMPD). Linear mixed models were used to evaluate the treatment effect on outcome measures. RESULTS The goal enrollment of 60 patients was not met due to the coronavirus disease of 2019 pandemic, with 23 patients included in the analysis. There was no significant difference over the study period between the pirfenidone vs placebo groups with regards to the observed change in PRMfSAD (+4.2% vs -0.4%; p = 0.22), FEV1 (-3.5% vs -3.6%; p = 0.97), FVC (-1.9% vs -4.6%; p = 0.41), or PRMPD (-0.6% vs -2.5%; p = 0.30). The study treatment tolerance and adverse events were generally similar between the pirfenidone and placebo groups. CONCLUSIONS Pirfenidone had no apparent impact on radiographic evidence of allograft dysfunction or pulmonary function decline in a single-center randomized trial of CLAD patients that did not meet enrollment goals but had an acceptable tolerance and side-effect profile.
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Affiliation(s)
- Michael P Combs
- Department of Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Elizabeth A Belloli
- Department of Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | | | - Kevin R Flaherty
- Department of Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Susan Murray
- School of Public Health, University of Michigan, Ann Arbor, Michigan
| | - Craig J Galbán
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Vibha N Lama
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Emory University, Atlanta, Georgia.
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Bell AJ, Pal R, Labaki WW, Hoff BA, Wang JM, Murray S, Kazerooni EA, Galban S, Lynch DA, Humphries SM, Martinez FJ, Hatt CR, Han MK, Ram S, Galban CJ. Local heterogeneity of normal lung parenchyma and small airways disease are associated with COPD severity and progression. Respir Res 2024; 25:106. [PMID: 38419014 PMCID: PMC10903150 DOI: 10.1186/s12931-024-02729-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 02/13/2024] [Indexed: 03/02/2024] Open
Abstract
BACKGROUND Small airways disease (SAD) is a major cause of airflow obstruction in COPD patients and has been identified as a precursor to emphysema. Although the amount of SAD in the lungs can be quantified using our Parametric Response Mapping (PRM) approach, the full breadth of this readout as a measure of emphysema and COPD progression has yet to be explored. We evaluated topological features of PRM-derived normal parenchyma and SAD as surrogates of emphysema and predictors of spirometric decline. METHODS PRM metrics of normal lung (PRMNorm) and functional SAD (PRMfSAD) were generated from CT scans collected as part of the COPDGene study (n = 8956). Volume density (V) and Euler-Poincaré Characteristic (χ) image maps, measures of the extent and coalescence of pocket formations (i.e., topologies), respectively, were determined for both PRMNorm and PRMfSAD. Association with COPD severity, emphysema, and spirometric measures were assessed via multivariable regression models. Readouts were evaluated as inputs for predicting FEV1 decline using a machine learning model. RESULTS Multivariable cross-sectional analysis of COPD subjects showed that V and χ measures for PRMfSAD and PRMNorm were independently associated with the amount of emphysema. Readouts χfSAD (β of 0.106, p < 0.001) and VfSAD (β of 0.065, p = 0.004) were also independently associated with FEV1% predicted. The machine learning model using PRM topologies as inputs predicted FEV1 decline over five years with an AUC of 0.69. CONCLUSIONS We demonstrated that V and χ of fSAD and Norm have independent value when associated with lung function and emphysema. In addition, we demonstrated that these readouts are predictive of spirometric decline when used as inputs in a ML model. Our topological PRM approach using PRMfSAD and PRMNorm may show promise as an early indicator of emphysema onset and COPD progression.
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Affiliation(s)
- Alexander J Bell
- Department of Radiology, University of Michigan, 109 Zina Pitcher Place BSRB A506, Ann Arbor, MI, 48109-2200, USA
| | - Ravi Pal
- Department of Radiology, University of Michigan, 109 Zina Pitcher Place BSRB A506, Ann Arbor, MI, 48109-2200, USA
| | - Wassim W Labaki
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Benjamin A Hoff
- Department of Radiology, University of Michigan, 109 Zina Pitcher Place BSRB A506, Ann Arbor, MI, 48109-2200, USA
| | - Jennifer M Wang
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Susan Murray
- School of Public Health, University of Michigan, Ann Arbor, MI, USA
| | - Ella A Kazerooni
- Department of Radiology, University of Michigan, 109 Zina Pitcher Place BSRB A506, Ann Arbor, MI, 48109-2200, USA
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Stefanie Galban
- Department of Radiology, University of Michigan, 109 Zina Pitcher Place BSRB A506, Ann Arbor, MI, 48109-2200, USA
| | - David A Lynch
- Department of Radiology, National Jewish Health, Denver, CO, USA
| | | | | | | | - MeiLan K Han
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Sundaresh Ram
- Department of Radiology, University of Michigan, 109 Zina Pitcher Place BSRB A506, Ann Arbor, MI, 48109-2200, USA.
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
| | - Craig J Galban
- Department of Radiology, University of Michigan, 109 Zina Pitcher Place BSRB A506, Ann Arbor, MI, 48109-2200, USA.
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
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Nakamura H, Hirai T, Kurosawa H, Hamada K, Matsunaga K, Shimizu K, Konno S, Muro S, Fukunaga K, Nakano Y, Kuwahira I, Hanaoka M. Current advances in pulmonary functional imaging. Respir Investig 2024; 62:49-65. [PMID: 37948969 DOI: 10.1016/j.resinv.2023.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 08/26/2023] [Accepted: 09/07/2023] [Indexed: 11/12/2023]
Abstract
Recent advances in imaging analysis have enabled evaluation of ventilation and perfusion in specific regions by chest computed tomography (CT) and magnetic resonance imaging (MRI), in addition to modalities including dynamic chest radiography, scintigraphy, positron emission tomography (PET), ultrasound, and electrical impedance tomography (EIT). In this review, an overview of current functional imaging techniques is provided for each modality. Advances in chest CT have allowed for the analysis of local volume changes and small airway disease in addition to emphysema, using the Jacobian determinant and parametric response mapping with inspiratory and expiratory images. Airway analysis can reveal characteristics of airway lesions in chronic obstructive pulmonary disease (COPD) and bronchial asthma, and the contribution of dysanapsis to obstructive diseases. Chest CT is also employed to measure pulmonary blood vessels, interstitial lung abnormalities, and mediastinal and chest wall components including skeletal muscle and bone. Dynamic CT can visualize lung deformation in respective portions. Pulmonary MRI has been developed for the estimation of lung ventilation and perfusion, mainly using hyperpolarized 129Xe. Oxygen-enhanced and proton-based MRI, without a polarizer, has potential clinical applications. Dynamic chest radiography is gaining traction in Japan for ventilation and perfusion analysis. Single photon emission CT can be used to assess ventilation-perfusion (V˙/Q˙) mismatch in pulmonary vascular diseases and COPD. PET/CT V˙/Q˙ imaging has also been demonstrated using "Galligas". Both ultrasound and EIT can detect pulmonary edema caused by acute respiratory distress syndrome. Familiarity with these functional imaging techniques will enable clinicians to utilize these systems in clinical practice.
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Affiliation(s)
- Hidetoshi Nakamura
- Department of Respiratory Medicine, Saitama Medical University, Saitama, Japan.
| | - Toyohiro Hirai
- Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hajime Kurosawa
- Center for Environmental Conservation and Research Safety and Department of Occupational Health, Tohoku University School of Medicine, Sendai, Japan
| | - Kazuki Hamada
- Department of Respiratory Medicine and Infectious Disease, Graduate School of Medicine, Yamaguchi University, Ube, Japan
| | - Kazuto Matsunaga
- Department of Respiratory Medicine and Infectious Disease, Graduate School of Medicine, Yamaguchi University, Ube, Japan
| | - Kaoruko Shimizu
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University, Sapporo, Japan
| | - Satoshi Konno
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University, Sapporo, Japan
| | - Shigeo Muro
- Department of Respiratory Medicine, Nara Medical University, Nara, Japan
| | - Koichi Fukunaga
- Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Yasutaka Nakano
- Division of Respiratory Medicine, Department of Internal Medicine, Shiga University of Medical Science, Otsu, Japan
| | - Ichiro Kuwahira
- Division of Pulmonary Medicine, Department of Medicine, Tokai University Tokyo Hospital, Tokyo, Japan
| | - Masayuki Hanaoka
- First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto, Japan
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Vasileva A, Hanafi N, Huszti E, Matelski J, Belousova N, Wu JKY, Martinu T, Ghany R, Keshavjee S, Tikkanen J, Cypel M, Yeung JC, Ryan CM, Chow CW. Intra-subject variability in oscillometry correlates with acute rejection and CLAD post-lung transplant. Front Med (Lausanne) 2023; 10:1158870. [PMID: 37305133 PMCID: PMC10248398 DOI: 10.3389/fmed.2023.1158870] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/04/2023] [Indexed: 06/13/2023] Open
Abstract
Background Chronic lung allograft dysfunction (CLAD) is the major cause of death post-lung transplantation, with acute cellular rejection (ACR) being the biggest contributing risk factor. Although patients are routinely monitored with spirometry, FEV1 is stable or improving in most ACR episodes. In contrast, oscillometry is highly sensitive to respiratory mechanics and shown to track graft injury associated with ACR and its improvement following treatment. We hypothesize that intra-subject variability in oscillometry measurements correlates with ACR and risk of CLAD. Methods Of 289 bilateral lung recipients enrolled for oscillometry prior to laboratory-based spirometry between December 2017 and March 2020, 230 had ≥ 3 months and 175 had ≥ 6 months of follow-up. While 37 patients developed CLAD, only 29 had oscillometry at time of CLAD onset and were included for analysis. These 29 CLAD patients were time-matched with 129 CLAD-free recipients. We performed multivariable regression to investigate the associations between variance in spirometry/oscillometry and the A-score, a cumulative index of ACR, as our predictor of primary interest. Conditional logistic regression models were built to investigate associations with CLAD. Results Multivariable regression showed that the A-score was positively associated with the variance in oscillometry measurements. Conditional logistic regression models revealed that higher variance in the oscillometry metrics of ventilatory inhomogeneity, X5, AX, and R5-19, was independently associated with increased risk of CLAD (p < 0.05); no association was found for variance in %predicted FEV1. Conclusion Oscillometry tracks graft injury and recovery post-transplant. Monitoring with oscillometry could facilitate earlier identification of graft injury, prompting investigation to identify treatable causes and decrease the risk of CLAD.
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Affiliation(s)
- Anastasiia Vasileva
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Nour Hanafi
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Ella Huszti
- Biostatistics Research Unit, University Health Network, Toronto, ON, Canada
| | - John Matelski
- Biostatistics Research Unit, University Health Network, Toronto, ON, Canada
| | - Natalia Belousova
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Joyce K. Y. Wu
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Tereza Martinu
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Rasheed Ghany
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Shaf Keshavjee
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
- Division of Thoracic Surgery, Department of Surgery, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Jussi Tikkanen
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
| | - Marcelo Cypel
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
- Division of Thoracic Surgery, Department of Surgery, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Jonathan C. Yeung
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
- Division of Thoracic Surgery, Department of Surgery, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Clodagh M. Ryan
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Pulmonary Function Laboratory, University Health Network, Toronto, ON, Canada
| | - Chung-Wai Chow
- Division of Respirology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Toronto Lung Transplant Program, Ajmera Multi-Organ Transplant Unit, University Health Network, Toronto, ON, Canada
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Halitim P, Tissot A. [Chronic lung allograft dysfunction in 2022, past and updates]. Rev Mal Respir 2023; 40:324-334. [PMID: 36858879 DOI: 10.1016/j.rmr.2023.01.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 01/24/2023] [Indexed: 03/03/2023]
Abstract
INTRODUCTION While short-term results of lung transplantation have improved considerably, long-term survival remains below that achieved for other solid organ transplants. CURRENT KNOWLEDGE The main cause of late mortality is chronic lung allograft dysfunction (CLAD), which affects nearly half of the recipients 5 years after transplantation. Immunological and non-immune risk factors have been identified. These factors activate the innate and adaptive immune system, leading to lesional and altered wound-healing processes, which result in fibrosis affecting the small airways or interstitial tissue. Several phenotypes of CLAD have been identified based on respiratory function and imaging pattern. Aside from retransplantation, which is possible for only small number of patients, no treatment can reverse the CLAD process. PERSPECTIVES Current therapeutic research is focused on anti-fibrotic treatments and photopheresis. Basic research has identified numerous biomarkers that could prove to be relevant as therapeutic targets. CONCLUSION While the pathophysiological mechanisms of CLAD are better understood than before, a major therapeutic challenge remains.
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Affiliation(s)
- P Halitim
- Service de pneumologie et soins intensifs, Hôpital européen Georges-Pompidou, Assistance publique-Hôpitaux de Paris, 75015 Paris, France; Service de pneumologie, CHU de Nantes, l'Institut du thorax, Nantes Université, Inserm, Center for Research in Transplantation and Translational Immunology, UMR 1064, 44093 Nantes cedex, France
| | - A Tissot
- Service de pneumologie, CHU de Nantes, l'Institut du thorax, Nantes Université, Inserm, Center for Research in Transplantation and Translational Immunology, UMR 1064, 44093 Nantes cedex, France.
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Pennati F, Leo L, Ferrini E, Sverzellati N, Bernardi D, Stellari FF, Aliverti A. Micro-CT-derived ventilation biomarkers for the longitudinal assessment of pathology and response to therapy in a mouse model of lung fibrosis. Sci Rep 2023; 13:4462. [PMID: 36932122 PMCID: PMC10023700 DOI: 10.1038/s41598-023-30402-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 02/22/2023] [Indexed: 03/19/2023] Open
Abstract
Experimental in-vivo animal models are key tools to investigate the pathogenesis of lung disease and to discover new therapeutics. Histopathological and biochemical investigations of explanted lung tissue are currently considered the gold standard, but they provide space-localized information and are not amenable to longitudinal studies in individual animals. Here, we present an imaging procedure that uses micro-CT to extract morpho-functional indicators of lung pathology in a murine model of lung fibrosis. We quantified the decrease of lung ventilation and measured the antifibrotic effect of Nintedanib. A robust structure-function relationship was revealed by cumulative data correlating micro-CT with histomorphometric endpoints. The results highlight the potential of in-vivo micro-CT biomarkers as novel tools to monitor the progression of inflammatory and fibrotic lung disease and to shed light on the mechanism of action of candidate drugs. Our platform is also expected to streamline translation from preclinical studies to human patients.
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Affiliation(s)
- Francesca Pennati
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy
| | - Ludovica Leo
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Erica Ferrini
- Department of Veterinary Science, University of Parma, Parma, Italy
| | | | - Davide Bernardi
- Department of Veterinary Science, University of Parma, Parma, Italy
| | - Franco Fabio Stellari
- Pharmacology and Toxicology Department Corporate Pre-Clinical R&D, Chiesi Farmaceutici S.P.A., Largo Belloli 11/A 43122, Parma, Italy.
| | - Andrea Aliverti
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy
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8
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Biomarkers for Chronic Lung Allograft Dysfunction: Ready for Prime Time? Transplantation 2023; 107:341-350. [PMID: 35980878 PMCID: PMC9875844 DOI: 10.1097/tp.0000000000004270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Chronic lung allograft dysfunction (CLAD) remains a major hurdle impairing lung transplant outcome. Parallel to the better clinical identification and characterization of CLAD and CLAD phenotypes, there is an increasing urge to find adequate biomarkers that could assist in the earlier detection and differential diagnosis of CLAD phenotypes, as well as disease prognostication. The current status and state-of-the-art of biomarker research in CLAD will be discussed with a particular focus on radiological biomarkers or biomarkers found in peripheral tissue, bronchoalveolar lavage' and circulating blood' in which significant progress has been made over the last years. Ultimately, although a growing number of biomarkers are currently being embedded in the follow-up of lung transplant patients, it is clear that one size does not fit all. The future of biomarker research probably lies in the rigorous combination of clinical information with findings in tissue, bronchoalveolar lavage' or blood. Only by doing so, the ultimate goal of biomarker research can be achieved, which is the earlier identification of CLAD before its clinical manifestation. This is desperately needed to improve the prognosis of patients with CLAD after lung transplantation.
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9
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Hsia CCW, Bates JHT, Driehuys B, Fain SB, Goldin JG, Hoffman EA, Hogg JC, Levin DL, Lynch DA, Ochs M, Parraga G, Prisk GK, Smith BM, Tawhai M, Vidal Melo MF, Woods JC, Hopkins SR. Quantitative Imaging Metrics for the Assessment of Pulmonary Pathophysiology: An Official American Thoracic Society and Fleischner Society Joint Workshop Report. Ann Am Thorac Soc 2023; 20:161-195. [PMID: 36723475 PMCID: PMC9989862 DOI: 10.1513/annalsats.202211-915st] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Multiple thoracic imaging modalities have been developed to link structure to function in the diagnosis and monitoring of lung disease. Volumetric computed tomography (CT) renders three-dimensional maps of lung structures and may be combined with positron emission tomography (PET) to obtain dynamic physiological data. Magnetic resonance imaging (MRI) using ultrashort-echo time (UTE) sequences has improved signal detection from lung parenchyma; contrast agents are used to deduce airway function, ventilation-perfusion-diffusion, and mechanics. Proton MRI can measure regional ventilation-perfusion ratio. Quantitative imaging (QI)-derived endpoints have been developed to identify structure-function phenotypes, including air-blood-tissue volume partition, bronchovascular remodeling, emphysema, fibrosis, and textural patterns indicating architectural alteration. Coregistered landmarks on paired images obtained at different lung volumes are used to infer airway caliber, air trapping, gas and blood transport, compliance, and deformation. This document summarizes fundamental "good practice" stereological principles in QI study design and analysis; evaluates technical capabilities and limitations of common imaging modalities; and assesses major QI endpoints regarding underlying assumptions and limitations, ability to detect and stratify heterogeneous, overlapping pathophysiology, and monitor disease progression and therapeutic response, correlated with and complementary to, functional indices. The goal is to promote unbiased quantification and interpretation of in vivo imaging data, compare metrics obtained using different QI modalities to ensure accurate and reproducible metric derivation, and avoid misrepresentation of inferred physiological processes. The role of imaging-based computational modeling in advancing these goals is emphasized. Fundamental principles outlined herein are critical for all forms of QI irrespective of acquisition modality or disease entity.
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10
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Mahdavi MMB, Arabfard M, Rafati M, Ghanei M. A Computer-based Analysis for Identification and Quantification of Small Airway Disease in Lung Computed Tomography Images: A Comprehensive Review for Radiologists. J Thorac Imaging 2023; 38:W1-W18. [PMID: 36206107 DOI: 10.1097/rti.0000000000000683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Computed tomography (CT) imaging is being increasingly used in clinical practice for detailed characterization of lung diseases. Respiratory diseases involve various components of the lung, including the small airways. Evaluation of small airway disease on CT images is challenging as the airways cannot be visualized directly by a CT scanner. Small airway disease can manifest as pulmonary air trapping (AT). Although AT may be sometimes seen as mosaic attenuation on expiratory CT images, it is difficult to identify diffuse AT visually. Computer technology advances over the past decades have provided methods for objective quantification of small airway disease on CT images. Quantitative CT (QCT) methods are being rapidly developed to quantify underlying lung diseases with greater precision than subjective visual assessment of CT images. A growing body of evidence suggests that QCT methods can be practical tools in the clinical setting to identify and quantify abnormal regions of the lung accurately and reproducibly. This review aimed to describe the available methods for the identification and quantification of small airway disease on CT images and to discuss the challenges of implementing QCT metrics in clinical care for patients with small airway disease.
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Affiliation(s)
- Mohammad Mehdi Baradaran Mahdavi
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran
| | - Masoud Arabfard
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran
| | - Mehravar Rafati
- Department of Medical Physics and Radiology, Faculty of paramedicine, Kashan University of Medical Sciences, Kashan, Iran
| | - Mostafa Ghanei
- Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran
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Abstract
Lung transplantation provides a treatment option for many individuals with advanced lung disease due to cystic fibrosis (CF). Since the first transplants for CF in the 1980s, survival has improved and the opportunity for transplant has expanded to include individuals who previously were not considered candidates for transplant. Criteria to be a transplant candidate vary significantly among transplant programs, highlighting that the engagement in more than one transplant program may be necessary. Individuals with highly resistant CF pathogens, malnutrition, osteoporosis, CF liver disease, and other comorbidities may be suitable candidates for lung transplant, or if needed, multi-organ transplant. The transplant process involves several phases, from discussion of prognosis and referral to a transplant center, to transplant evaluation, to listing, transplant surgery, and care after transplant. While the availability of highly effective CF transmembrane conductance regulator (CFTR) modulators for many individuals with CF has improved lung function and slowed progression to respiratory failure, early discussion regarding transplant as a treatment option and referral to a transplant program are critical to maximizing opportunity and optimizing patient and family experience. The decision to be evaluated for transplant and to list for transplant are distinct, and early referral may provide a treatment option that can be urgently executed if needed. Survival after transplant for CF is improving, to a median survival of approximately 10 years, and most transplant survivors enjoy significant improvement in quality of life.
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12
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Davis CW, Lopez CL, Bell AJ, Miller RF, Rabin AS, Murray S, Falvo MJ, Han MK, Galban CJ, Osterholzer JJ. The Severity of Functional Small Airway Disease in Military Personnel with Constrictive Bronchiolitis as Measured by Quantitative Computed Tomography. Am J Respir Crit Care Med 2022; 206:786-789. [PMID: 35608541 DOI: 10.1164/rccm.202201-0153le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
| | | | | | | | - Alexander S Rabin
- University of Michigan Ann Arbor, Michigan.,VA Ann Arbor Health Care System Ann Arbor, Michigan
| | | | - Michael J Falvo
- Rutgers University Newark, New Jersey.,VA New Jersey Health Care System East Orange, New Jersey
| | | | | | - John J Osterholzer
- University of Michigan Ann Arbor, Michigan.,VA Ann Arbor Health Care System Ann Arbor, Michigan
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13
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Abstract
Chronic lung allograft dysfunction (CLAD) is a syndrome of progressive lung function decline, subcategorized into obstructive, restrictive, and mixed phenotypes. The trajectory of CLAD is variable depending on the phenotype, with restrictive and mixed phenotypes having more rapid progression and lower survival. The mechanisms driving CLAD development remain unclear, though allograft injury during primary graft dysfunction, acute cellular rejection, antibody-mediated rejection, and infections trigger immune responses with long-lasting effects that can lead to CLAD months or years later. Currently, retransplantation is the only effective treatment.
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Affiliation(s)
- Aida Venado
- Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, University of California, San Francisco, 505 Parnassus Ave, M1093A, San Francisco, CA 94143-2204, USA.
| | - Jasleen Kukreja
- Division of Cardiothoracic Surgery, Univeristy of California, San Francisco, 500 Parnassus Ave, MU 405W Suite 305, San Francisco, CA 94143, USA
| | - John R Greenland
- Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, University of California, San Francisco, SF VAHCS Building 2, Room 453 (Mail stop 111D), 4150 Clement St, San Francisco CA 94121, USA
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14
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Owen DR, Sun Y, Irrer JC, Schipper MJ, Schonewolf CA, Galbán S, Jolly S, Haken RKT, Galbán C, Matuszak M. Investigating the Incidence of Pulmonary Abnormalities as Identified by Parametric Response Mapping in Lung Cancer Patients Prior to Radiation Treatment. Adv Radiat Oncol 2022; 7:100980. [PMID: 35693252 PMCID: PMC9184868 DOI: 10.1016/j.adro.2022.100980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 12/14/2021] [Indexed: 12/02/2022] Open
Abstract
Purpose Parametric response mapping (PRM) of high-resolution, paired inspiration and expiration computed tomography (CT) scans is a promising analytical imaging technique that is currently used in diagnostic applications and offers the ability to characterize and quantify certain pulmonary pathologies on a patient-specific basis. As one of the first studies to implement such a technique in the radiation oncology clinic, the goal of this work was to assess the feasibility for PRM analysis to identify pulmonary abnormalities in patients with lung cancer before radiation therapy (RT). Methods and Materials High-resolution, paired inspiration and expiration CT scans were acquired from 23 patients with lung cancer as part of routine treatment planning CT acquisition. When applied to the paired CT scans, PRM analysis classifies lung parenchyma, on a voxel-wise basis, as normal, small airways disease (SAD), emphysema, or parenchymal disease (PD). PRM classifications were quantified as a percent of total lung volume and were evaluated globally and regionally within the lung. Results PRM analysis of pre-RT CT scans was successfully implemented using a workflow that produced patient-specific maps and quantified specific phenotypes of pulmonary abnormalities. Through this study, a large prevalence of SAD and PD was demonstrated in this lung cancer patient population, with global averages of 10% and 17%, respectively. Moreover, PRM-classified normal and SAD in the region with primary tumor involvement were found to be significantly different from global lung values. When present, elevated levels of PD and SAD abnormalities tended to be pervasive in multiple regions of the lung, indicating a large burden of underlying disease. Conclusions Pulmonary abnormalities, as detected by PRM, were characterized in patients with lung cancer scheduled for RT. Although further study is needed, PRM is a highly accessible CT-based imaging technique that has the potential to identify local lung abnormalities associated with chronic obstructive pulmonary disease and interstitial lung disease. Further investigation in the radiation oncology setting may provide strategies for tailoring RT planning and risk assessment based on pre-existing PRM-based pathology.
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Affiliation(s)
- Daniel R. Owen
- Departments of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
- Corresponding author: Daniel 'Rocky' Owen, PhD
| | - Yilun Sun
- Departments of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
- Departments of Biostatistics, University of Michigan, Ann Arbor, Michigan
| | - Jim C. Irrer
- Departments of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
| | | | | | - Stefanie Galbán
- Departments of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Shruti Jolly
- Departments of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
| | | | - C.J. Galbán
- Departments of Radiology, University of Michigan, Ann Arbor, Michigan
| | - M.M. Matuszak
- Departments of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
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15
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Quantitative CT Correlates with Local Inflammation in Lung of Patients with Subtypes of Chronic Lung Allograft Dysfunction. Cells 2022; 11:cells11040699. [PMID: 35203345 PMCID: PMC8870691 DOI: 10.3390/cells11040699] [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: 12/01/2021] [Revised: 02/08/2022] [Accepted: 02/11/2022] [Indexed: 02/03/2023] Open
Abstract
Chronic rejection of lung allografts has two major subtypes, bronchiolitis obliterans syndrome (BOS) and restrictive allograft syndrome (RAS), which present radiologically either as air trapping with small airways disease or with persistent pleuroparenchymal opacities. Parametric response mapping (PRM), a computed tomography (CT) methodology, has been demonstrated as an objective readout of BOS and RAS and bears prognostic importance, but has yet to be correlated to biological measures. Using a topological technique, we evaluate the distribution and arrangement of PRM-derived classifications of pulmonary abnormalities from lung transplant recipients undergoing redo-transplantation for end-stage BOS (N = 6) or RAS (N = 6). Topological metrics were determined from each PRM classification and compared to structural and biological markers determined from microCT and histopathology of lung core samples. Whole-lung measurements of PRM-defined functional small airways disease (fSAD), which serves as a readout of BOS, were significantly elevated in BOS versus RAS patients (p = 0.01). At the core-level, PRM-defined parenchymal disease, a potential readout of RAS, was found to correlate to neutrophil and collagen I levels (p < 0.05). We demonstrate the relationship of structural and biological markers to the CT-based distribution and arrangement of PRM-derived readouts of BOS and RAS.
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16
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Baron R, Kadlecek S, Loza L, Xin Y, Amzajerdian F, Duncan I, Hamedani H, Rizi R. Deriving Regionally Specific Biomarkers of Emphysema and Small Airways Disease Using Variable Threshold Parametric Response Mapping on Volumetric Lung CT Images. Acad Radiol 2022; 29 Suppl 2:S127-S136. [PMID: 34272162 PMCID: PMC8755853 DOI: 10.1016/j.acra.2021.05.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/20/2021] [Accepted: 05/21/2021] [Indexed: 02/03/2023]
Abstract
PURPOSE This study aims to develop and validate a parametric response mapping (PRM) methodology to accurately identify diseased regions of the lung by using variable thresholds to account for alterations in regional lung function between the gravitationally-independent (anterior) and gravitationally-dependent (posterior) lung in CT images acquired in the supine position. METHODS 34 male Sprague-Dawley rats (260-540 g) were imaged, 4 of which received elastase injection (100 units/kg) as a model for emphysema (EMPH). Gated volumetric CT was performed at end-inspiration (EI) and end-expiration (EE) on separate groups of free-breathing (n = 20) and ventilated (n = 10) rats in the supine position. To derive variable thresholds for the new PRM methodology, voxels were first grouped into 100 bins based on the fractional distance along the anterior-to-posterior direction. Lower limits of normal (LLN) for x-ray attenuation in each bin were set by determining the smallest region that enclosed 98% of voxels from healthy, ventilated animals. RESULTS When utilizing fixed thresholds in the conventional PRM methodology, a distinct posterior-anterior gradient was seen, in which nearly the entire posterior region of the lung was identified as HEALTHY, while the anterior lung was labeled as significantly less so (t(29) = -3.27, p = 0.003). In both cohorts, %SAD progressively increased from posterior to anterior, while %HEALTHY lung decreased in the same direction. After applying our PRM methodology with variable thresholds to the same rat images, the posterior-anterior trend in %SAD quantification was removed from all rats and the significant increase of diseased lung in the anterior was removed. CONCLUSIONS The PRM methodology using variable thresholds provides regionally specific markers of %SAD and %EMPH by correcting for alterations in regional lung function associated with the naturally occurring vertical gradient of dependent vs. non-dependent lung density and compliance.
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Affiliation(s)
- Ryan Baron
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Steve Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Luis Loza
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yi Xin
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Faraz Amzajerdian
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ian Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rahim Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
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17
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McInnis MC, Ma J, Karur GR, Houbois C, Levy L, Havlin J, Fuchs E, Tikkanen J, Chow CW, Huszti E, Martinu T. Chronic lung allograft dysfunction phenotype and prognosis by machine learning CT analysis. Eur Respir J 2021; 60:13993003.01652-2021. [PMID: 34949699 DOI: 10.1183/13993003.01652-2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 11/23/2021] [Indexed: 11/05/2022]
Abstract
BACKGROUND Chronic lung allograft dysfunction (CLAD) is the principal cause of graft failure in lung transplant recipients and prognosis depends on CLAD phenotype. We used machine learning computed tomography (CT) lung texture analysis tool at CLAD diagnosis for phenotyping and prognostication compared to radiologists' scoring. METHODS This retrospective study included all adult first double-lung transplant patients (01/2010-12/2015) with CLAD (censored 12/2019) and inspiratory CT near CLAD diagnosis. The machine learning tool quantified ground-glass opacity, reticulation, hyperlucent lung, and pulmonary vessel volume (PVV). Two radiologists scored for ground-glass opacity, reticulation, consolidation, pleural effusion, air trapping and bronchiectasis. Receiver operating characteristic curve analysis was used to evaluate the diagnostic performance of machine learning and radiologist for CLAD phenotype. Multivariable Cox proportional-hazards regression analysis for allograft survival controlled for age, sex, native lung disease, cytomegalovirus serostatus, and CLAD phenotype (bronchiolitis obliterans syndrome [BOS] and restrictive allograft syndrome [RAS]/mixed). RESULTS 88 patients were included (57 BOS, 20 RAS/mixed, and 11 unclassified/undefined) with CT a median 9.5 days from CLAD onset. Radiologist and machine learning parameters phenotyped RAS/mixed with PVV as the strongest indicator (AUC 0.85). Machine learning hyperlucent lung phenotyped BOS using only inspiratory CT (AUC=0.76). Radiologist and machine learning parameters predicted graft failure in the multivariable analysis, best with PVV (HR=1.23, 95%CI 1.05-1.44, p=0.01). CONCLUSIONS Machine learning discriminated between CLAD phenotypes on CT. Both radiologist and machine learning scoring were associated with graft failure, independent of CLAD phenotype. PVV, unique to machine learning, was the strongest in phenotyping and prognostication.
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Affiliation(s)
- Micheal C McInnis
- Department of Medical Imaging, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Jin Ma
- Biostatistics Research Unit, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Gauri Rani Karur
- Department of Medical Imaging, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Christian Houbois
- Department of Medical Imaging, University Health Network, University of Toronto, Toronto, ON, Canada.,Department of Diagnostic and Interventional Radiology, University of Cologne, Cologne, Germany
| | - Liran Levy
- Toronto Lung Transplant Program, Ajmera Transplant Centre, University Health Network, Toronto, ON, Canada
| | - Jan Havlin
- Toronto Lung Transplant Program, Ajmera Transplant Centre, University Health Network, Toronto, ON, Canada
| | - Eyal Fuchs
- Toronto Lung Transplant Program, Ajmera Transplant Centre, University Health Network, Toronto, ON, Canada
| | - Jussi Tikkanen
- Toronto Lung Transplant Program, Ajmera Transplant Centre, University Health Network, Toronto, ON, Canada
| | - Chung-Wai Chow
- Toronto Lung Transplant Program, Ajmera Transplant Centre, University Health Network, Toronto, ON, Canada.,Division of Respirology, Department of Medicine, University of Toronto, ON, Canada
| | - Ella Huszti
- Biostatistics Research Unit, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Tereza Martinu
- Toronto Lung Transplant Program, Ajmera Transplant Centre, University Health Network, Toronto, ON, Canada.,Division of Respirology, Department of Medicine, University of Toronto, ON, Canada
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18
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Kogo M, Matsumoto H, Tanabe N, Chen-Yoshikawa TF, Nakajima N, Yoshizawa A, Oguma T, Sato S, Nomura N, Morimoto C, Sunadome H, Gotoh S, Ohsumi A, Date H, Hirai T. The importance of central airway dilatation in patients with bronchiolitis obliterans. ERJ Open Res 2021; 7:00123-2021. [PMID: 34708115 PMCID: PMC8542961 DOI: 10.1183/23120541.00123-2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 06/02/2021] [Indexed: 12/03/2022] Open
Abstract
Background Bronchiolitis obliterans (BO) is a clinical syndrome characterised by progressive small airway obstruction, causing significant morbidity and mortality. Central airway dilatation is one of its radiological characteristics, but little is known about the clinical and pathological associations between airway dilatation and BO. Methods This retrospective study consecutively included patients who underwent lung transplantation due to BO at Kyoto University Hospital from 2009 to 2019. Demographic and histopathological findings of the resected lungs were compared between patients with and without airway dilatation measured by chest computed tomography (CT) at registration for lung transplantation. Results Of a total of 38 included patients (median age, 30 years), 34 (89%) had a history of hematopoietic stem-cell transplantation, and 22 (58%) had airway dilatation based on CT. Patients with airway dilatation had a higher frequency of Pseudomonas aeruginosa isolation with greater residual volume than those without airway dilatation. Quantitative CT analysis revealed an increase in lung volume to predictive total lung capacity and a percentage of low attenuation volume <−950 HU at inspiration in association with the extent of airway dilatation. Airway dilatation on CT was associated with an increased number of bronchioles with concentric narrowing of the lumen and thickening of the subepithelium of the walls on histology. Conclusions In patients with BO, airway dilatation may reflect increased residual volume or air trapping and pathological extent of obstructive bronchioles, accompanied by a risk of Pseudomonas aeruginosa isolation. More attention should be paid to the development of airway dilatation in the management of BO. In patients with bronchiolitis obliterans (BO), airway dilatation may reflect air trapping and the pathological extent of obstructive bronchioles. More attention should be paid to airway dilatation in the management of BO.https://bit.ly/3w7cRV6
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Affiliation(s)
- Mariko Kogo
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hisako Matsumoto
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.,These authors contributed equally to this work
| | - Naoya Tanabe
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.,These authors contributed equally to this work
| | | | - Naoki Nakajima
- Dept of Diagnostic Pathology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Akihiko Yoshizawa
- Dept of Diagnostic Pathology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Tsuyoshi Oguma
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Susumu Sato
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Natsuko Nomura
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Chie Morimoto
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hironobu Sunadome
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shimpei Gotoh
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Akihiro Ohsumi
- Dept of Thoracic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hiroshi Date
- Dept of Thoracic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Toyohiro Hirai
- Dept of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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19
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Matrosic CK, Owen DR, Polan D, Sun Y, Jolly S, Schonewolf C, Schipper M, Haken RKT, Galban CJ, Matuszak M. Feasibility of function-guided lung treatment planning with parametric response mapping. J Appl Clin Med Phys 2021; 22:80-89. [PMID: 34697884 PMCID: PMC8598143 DOI: 10.1002/acm2.13436] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/04/2021] [Accepted: 09/14/2021] [Indexed: 11/18/2022] Open
Abstract
Purpose Recent advancements in functional lung imaging have been developed to improve clinicians’ knowledge of patient pulmonary condition prior to treatment. Ultimately, it may be possible to employ these functional imaging modalities to tailor radiation treatment plans to optimize patient outcome and mitigate pulmonary complications. Parametric response mapping (PRM) is a computed tomography (CT)–based functional lung imaging method that utilizes a voxel‐wise image analysis technique to classify lung abnormality phenotypes, and has previously been shown to be effective at assessing lung complication risk in diagnostic applications. The purpose of this work was to demonstrate the implementation of PRM guidance in radiotherapy treatment planning. Methods and materials A retrospective study was performed with 18 lung cancer patients to test the incorporation of PRM into a radiotherapy planning workflow. Paired inspiration/expiration pretreatment CT scans were acquired and PRM analysis was utilized to classify each voxel as normal, parenchymal disease, small airway disease, and emphysema. Density maps were generated for each PRM classification to contour high density regions of pulmonary abnormalities. Conventional volumetric‐modulated arc therapy and PRM‐guided treatment plans were designed for each patient. Results PRM guidance was successfully implemented into the treatment planning process. The inclusion of PRM priorities resulted in statistically significant (p < 0.05) improvements to the V20Gy within the PRM avoidance contours. On average, reductions of 5.4% in the V20Gy(%) were found. The PRM‐guided treatment plans did not significantly increase the dose to the organs at risk or result in insufficient planning target volume coverage, but did increase plan complexity. Conclusions PRM guidance was successfully implemented into a treatment planning workflow and shown to be effective for dose redistribution within the lung. This work has provided a framework for the potential clinical implementation of PRM‐guided treatment planning.
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Affiliation(s)
- Charles K Matrosic
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA
| | - D Rocky Owen
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA
| | - Daniel Polan
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA
| | - Yilun Sun
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA.,School of Public Health, University of Michigan, Ann Arbor, Michigan, USA
| | - Shruti Jolly
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA
| | - Caitlin Schonewolf
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA
| | - Matthew Schipper
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA.,School of Public Health, University of Michigan, Ann Arbor, Michigan, USA
| | - Randall K Ten Haken
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA
| | - Craig J Galban
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Martha Matuszak
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA
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20
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Li T, Zhou HP, Zhou ZJ, Guo LQ, Zhou L. Computed tomography-identified phenotypes of small airway obstructions in chronic obstructive pulmonary disease. Chin Med J (Engl) 2021; 134:2025-2036. [PMID: 34517376 PMCID: PMC8440009 DOI: 10.1097/cm9.0000000000001724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Indexed: 12/02/2022] Open
Abstract
ABSTRACT Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characteristic of small airway inflammation, obstruction, and emphysema. It is well known that spirometry alone cannot differentiate each separate component. Computed tomography (CT) is widely used to determine the extent of emphysema and small airway involvement in COPD. Compared with the pulmonary function test, small airway CT phenotypes can accurately reflect disease severity in patients with COPD, which is conducive to improving the prognosis of this disease. CT measurement of central airway morphology has been applied in clinical, epidemiologic, and genetic investigations as an inference of the presence and severity of small airway disease. This review will focus on presenting the current knowledge and methodologies in chest CT that aid in identifying discrete COPD phenotypes.
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Affiliation(s)
- Tao Li
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Department of Respiratory Medicine, Xuzhou First People's Hospital, Xuzhou, Jiangsu 221116, China
| | - Hao-Peng Zhou
- Department of Medicine, Jiangsu University School of Medicine, Zhenjiang, Jiangsu 212013, China
| | - Zhi-Jun Zhou
- Institute of Radio Frequency & Optical Electronics-Integrated Circuits, School of Information and Engineering, Southeast University, Nanjing, Jiangsu 210096, China
| | - Li-Quan Guo
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, Jiangsu 215163, China
| | - Linfu Zhou
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Institute of Integrative Medicine, Nanjing Medical University, Nanjing, Jiangsu 210029, China
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21
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Krings JG, Goss CW, Lew D, Samant M, McGregor MC, Boomer J, Bacharier LB, Sheshadri A, Hall C, Brownell J, Schechtman KB, Peterson S, McEleney S, Mauger DT, Fahy JV, Fain SB, Denlinger LC, Israel E, Washko G, Hoffman E, Wenzel SE, Castro M. Quantitative CT metrics are associated with longitudinal lung function decline and future asthma exacerbations: Results from SARP-3. J Allergy Clin Immunol 2021; 148:752-762. [PMID: 33577895 PMCID: PMC8349941 DOI: 10.1016/j.jaci.2021.01.029] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 12/02/2020] [Accepted: 01/08/2021] [Indexed: 01/07/2023]
Abstract
BACKGROUND Currently, there is limited knowledge regarding which imaging assessments of asthma are associated with accelerated longitudinal decline in lung function. OBJECTIVES We aimed to assess whether quantitative computed tomography (qCT) metrics are associated with longitudinal decline in lung function and morbidity in asthma. METHODS We analyzed 205 qCT scans of adult patients with asthma and calculated baseline markers of airway remodeling, lung density, and pointwise regional change in lung volume (Jacobian measures) for each participant. Using multivariable regression models, we then assessed the association of qCT measurements with the outcomes of future change in lung function, future exacerbation rate, and changes in validated measurements of morbidity. RESULTS Greater baseline wall area percent (β = -0.15 [95% CI = -0.26 to -0.05]; P < .01), hyperinflation percent (β = -0.25 [95% CI = -0.41 to -0.09]; P < .01), and Jacobian gradient measurements (cranial-caudal β = 10.64 [95% CI = 3.79-17.49]; P < .01; posterior-anterior β = -9.14, [95% CI = -15.49 to -2.78]; P < .01) were associated with more severe future lung function decline. Additionally, greater wall area percent (rate ratio = 1.06 [95% CI = 1.01-1.10]; P = .02) and air trapping percent (rate ratio =1.01 [95% CI = 1.00-1.02]; P = .03), as well as lower decline in the Jacobian determinant mean (rate ratio = 0.58 [95% CI = 0.41-0.82]; P < .01) and Jacobian determinant standard deviation (rate ratio = 0.52 [95% CI = 0.32-0.85]; P = .01), were associated with a greater rate of future exacerbations. However, imaging metrics were not associated with clinically meaningful changes in scores on validated asthma morbidity questionnaires. CONCLUSIONS Baseline qCT measures of more severe airway remodeling, more small airway disease and hyperinflation, and less pointwise regional change in lung volumes were associated with future lung function decline and asthma exacerbations.
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Affiliation(s)
- James G Krings
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, St Louis, Mo
| | - Charles W Goss
- Division of Biostatistics, Washington University in St Louis School of Medicine, St Louis, Mo
| | - Daphne Lew
- Division of Biostatistics, Washington University in St Louis School of Medicine, St Louis, Mo
| | - Maanasi Samant
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, St Louis, Mo
| | - Mary Clare McGregor
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, St Louis, Mo
| | - Jonathan Boomer
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, Kan
| | - Leonard B Bacharier
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tenn
| | - Ajay Sheshadri
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, The University of Texas M.D. Anderson Cancer Center, Houston, Tex
| | - Chase Hall
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, Kan
| | - Joshua Brownell
- Division of Allergy, Pulmonary, and Critical Care Medicine, Department of Medicine, University of Wisconsin, Madison, Wis
| | - Ken B Schechtman
- Division of Biostatistics, Washington University in St Louis School of Medicine, St Louis, Mo
| | | | | | - David T Mauger
- Division of Statistics and Bioinformatics, Department of Public Health Sciences, Pennsylvania State University, Hershey, Pa
| | - John V Fahy
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, the University of California San Francisco, San Francisco, Calif
| | - Sean B Fain
- Department of Radiology and Biomedical Engineering, University of Wisconsin, Madison, Wis
| | - Loren C Denlinger
- Division of Allergy, Pulmonary, and Critical Care Medicine, Department of Medicine, University of Wisconsin, Madison, Wis
| | - Elliot Israel
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Mass
| | - George Washko
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Mass
| | - Eric Hoffman
- Department of Radiology, Biomedical Engineering, and Medicine, University of Iowa, Iowa City, IA
| | - Sally E Wenzel
- Division of Pulmonary, Allergy, and Critical Care, Department of Medicine, the University of Pittsburgh, Pittsburgh, Pa
| | - Mario Castro
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, Kan.
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22
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Rozenberg D, McInnis M, Chow CW. Utilizing Automated Radiographic Signatures to Prognosticate Chronic Lung Allograft Dysfunction: What Does the Future Hold? Am J Respir Crit Care Med 2021; 204:883-885. [PMID: 34384039 PMCID: PMC8534617 DOI: 10.1164/rccm.202107-1726ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Dmitry Rozenberg
- University Health Network, 7989, Medicine, Respirology and Lung Transplantation , Toronto, Ontario, Canada;
| | - Micheal McInnis
- University Health Network, 7989, Joint Department of Medical Imaging, Toronto, Ontario, Canada
| | - Chung-Wai Chow
- University of Toronto, 7938, Medicine, Toronto, Ontario, Canada
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23
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Belloli EA, Gu T, Wang Y, Vummidi D, Lyu DM, Combs MP, Chughtai A, Murray S, Galbán CJ, Lama VN. Radiographic Graft Surveillance in Lung Transplantation: Prognostic Role of Parametric Response Mapping. Am J Respir Crit Care Med 2021; 204:967-976. [PMID: 34319850 DOI: 10.1164/rccm.202012-4528oc] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Chronic lung allograft dysfunction (CLAD) results in significant morbidity following lung transplantation. Potential CLAD occurs when lung function declines to 80-90% of baseline. Better non-invasive tools to prognosticate at potential CLAD are needed. OBJECTIVES To determine if parametric response mapping (PRM), a CT voxel-wise methodology, applied to high resolution CT scans can identify patients at risk of progression to CLAD or death. METHODS Radiographic features and PRM-based CT metrics quantifying functional small airways disease (PRMfSAD) and parenchymal disease (PRMPD) were studied at potential CLAD (n=61). High PRMfSAD and high PRMPD were defined as ≥ 30%. Restricted mean modeling was performed to compare CLAD-free survival among groups. MEASUREMENTS AND MAIN RESULTS PRM metrics identified 3 unique signatures: high PRMfSAD (11.5%), high PRMPD (41%) and neither (PRMNormal; 47.5%). Patients with high PRMfSAD or PRMPD had shorter CLAD-free median survival times (0.46 years and 0.50 years) compared to patients with predominantly PRMNormal (2.03 years; p=0.004 and 0.007 compared to PRMfSAD and PRMPD groups, respectively). In multivariate modeling adjusting for single versus double lung transplant, age at transplant, BMI at potential CLAD, and time from transplant to CT, PRMfSAD or PRMPD ≥ 30% continue to be statistically significant predictors of shorter CLAD-free survival. Air trapping by radiologist interpretation was common (66%), similar across PRM groups, and was not predictive of CLAD-free survival. Ground glass opacities by radiologist read occurred in 16% of cases and was associated with decreased CLAD-free survival (p<0.001). CONCLUSIONS PRM analysis offers valuable prognostic information at potential CLAD, identifying patients most at risk of developing CLAD or death.
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Affiliation(s)
- Elizabeth A Belloli
- University of Michigan, Pulmonary & Critical Care Medicine, Ann Arbor, Michigan, United States;
| | - Tian Gu
- University of Michigan, Biostatistics, Ann Arbor, Michigan, United States
| | - Yizhuo Wang
- University of Michigan School of Public Health, 51329, Biostatistics, Ann Arbor, Michigan, United States
| | - Dharshan Vummidi
- University of Michigan, Radiology, Ann Arbor, Michigan, United States
| | - Dennis M Lyu
- University of Michigan, Internal Medicine, Division Pulmonary & Critical Care, Ann Arbor, Michigan, United States
| | - Michael P Combs
- University of Michigan, Internal Medicine, Ann Arbor, Michigan, United States
| | - Aamer Chughtai
- University of Michigan, Radiology, Ann Arbor, Michigan, United States
| | - Susan Murray
- University of Michigan, School of Public Health, Biostatistics, Ann Arbor, Michigan, United States
| | - Craig J Galbán
- Center for Molecular Imaging, Michigan, Michigan, United States
| | - Vibha N Lama
- University of Michigan, 1259, Pulmonary and Critical Care Medicine, Ann Arbor, Michigan, United States
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24
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Hoang-Thi TN, Chassagnon G, Hua-Huy T, Boussaud V, Dinh-Xuan AT, Revel MP. Chronic Lung Allograft Dysfunction Post Lung Transplantation: A Review of Computed Tomography Quantitative Methods for Detection and Follow-Up. J Clin Med 2021; 10:jcm10081608. [PMID: 33920108 PMCID: PMC8069908 DOI: 10.3390/jcm10081608] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 12/27/2022] Open
Abstract
Chronic lung allograft dysfunction (CLAD) remains the leading cause of morbidity and mortality after lung transplantation. The term encompasses both obstructive and restrictive phenotypes, as well as mixed and undefined phenotypes. Imaging, in addition to pulmonary function tests, plays a major role in identifying the CLAD phenotype and is essential for follow-up after lung transplantation. Quantitative imaging allows for the performing of reader-independent precise evaluation of CT examinations. In this review article, we will discuss the role of quantitative imaging methods for evaluating the airways and the lung parenchyma on computed tomography (CT) images, for an early identification of CLAD and for prognostic estimation. We will also discuss their limits and the need for novel approaches to predict, understand, and identify CLAD in its early stages.
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Affiliation(s)
- Trieu-Nghi Hoang-Thi
- AP-HP.Centre, Hôpital Cochin, Department of Radiology, Université de Paris, 75014 Paris, France; (T.-N.H.-T.); (G.C.)
- Department of Diagnostic Imaging, Vinmec Central Park Hospital, Ho Chi Minh City 70000, Vietnam
- AP-HP.Centre, Hôpital Cochin, Department of Respiratory Physiology, Université de Paris, 75014 Paris, France; (T.H.-H.); (A.-T.D.-X.)
| | - Guillaume Chassagnon
- AP-HP.Centre, Hôpital Cochin, Department of Radiology, Université de Paris, 75014 Paris, France; (T.-N.H.-T.); (G.C.)
| | - Thong Hua-Huy
- AP-HP.Centre, Hôpital Cochin, Department of Respiratory Physiology, Université de Paris, 75014 Paris, France; (T.H.-H.); (A.-T.D.-X.)
| | - Veronique Boussaud
- AP-HP.Centre, Hôpital Cochin, Department of Pneumology, Université de Paris, 75014 Paris, France;
| | - Anh-Tuan Dinh-Xuan
- AP-HP.Centre, Hôpital Cochin, Department of Respiratory Physiology, Université de Paris, 75014 Paris, France; (T.H.-H.); (A.-T.D.-X.)
| | - Marie-Pierre Revel
- AP-HP.Centre, Hôpital Cochin, Department of Radiology, Université de Paris, 75014 Paris, France; (T.-N.H.-T.); (G.C.)
- Correspondence: ; Tel.: +33-1-5841-2471
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25
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Ram S, Hoff BA, Bell AJ, Galban S, Fortuna AB, Weinheimer O, Wielpütz MO, Robinson TE, Newman B, Vummidi D, Chughtai A, Kazerooni EA, Johnson TD, Han MK, Hatt CR, Galban CJ. Improved detection of air trapping on expiratory computed tomography using deep learning. PLoS One 2021; 16:e0248902. [PMID: 33760861 PMCID: PMC7990199 DOI: 10.1371/journal.pone.0248902] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/26/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Radiologic evidence of air trapping (AT) on expiratory computed tomography (CT) scans is associated with early pulmonary dysfunction in patients with cystic fibrosis (CF). However, standard techniques for quantitative assessment of AT are highly variable, resulting in limited efficacy for monitoring disease progression. OBJECTIVE To investigate the effectiveness of a convolutional neural network (CNN) model for quantifying and monitoring AT, and to compare it with other quantitative AT measures obtained from threshold-based techniques. MATERIALS AND METHODS Paired volumetric whole lung inspiratory and expiratory CT scans were obtained at four time points (0, 3, 12 and 24 months) on 36 subjects with mild CF lung disease. A densely connected CNN (DN) was trained using AT segmentation maps generated from a personalized threshold-based method (PTM). Quantitative AT (QAT) values, presented as the relative volume of AT over the lungs, from the DN approach were compared to QAT values from the PTM method. Radiographic assessment, spirometric measures, and clinical scores were correlated to the DN QAT values using a linear mixed effects model. RESULTS QAT values from the DN were found to increase from 8.65% ± 1.38% to 21.38% ± 1.82%, respectively, over a two-year period. Comparison of CNN model results to intensity-based measures demonstrated a systematic drop in the Dice coefficient over time (decreased from 0.86 ± 0.03 to 0.45 ± 0.04). The trends observed in DN QAT values were consistent with clinical scores for AT, bronchiectasis, and mucus plugging. In addition, the DN approach was found to be less susceptible to variations in expiratory deflation levels than the threshold-based approach. CONCLUSION The CNN model effectively delineated AT on expiratory CT scans, which provides an automated and objective approach for assessing and monitoring AT in CF patients.
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Affiliation(s)
- Sundaresh Ram
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Biomedical Engineering, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Benjamin A. Hoff
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Alexander J. Bell
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Stefanie Galban
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Aleksa B. Fortuna
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Oliver Weinheimer
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center, Heidelberg (TLRC), German Lung Research Center (DZL), Heidelberg, Germany
| | - Mark O. Wielpütz
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center, Heidelberg (TLRC), German Lung Research Center (DZL), Heidelberg, Germany
| | - Terry E. Robinson
- Department of Pediatrics, Center of Excellence in Pulmonary Biology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Beverley Newman
- Department of Pediatric Radiology, Lucile Packard Children’s Hospital at Stanford, Stanford, California, United States of America
| | - Dharshan Vummidi
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Aamer Chughtai
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Ella A. Kazerooni
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Internal Medicine, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Timothy D. Johnson
- Department of Biostatistics, University of Michigan, School of Public Health, Ann Arbor, Michigan, United States of America
| | - MeiLan K. Han
- Department of Internal Medicine, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Charles R. Hatt
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- Imbio LLC, Minneapolis, Minnesota, United States of America
| | - Craig J. Galban
- Department of Radiology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Biomedical Engineering, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
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26
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Byrne D, Nador RG, English JC, Yee J, Levy R, Bergeron C, Swiston JR, Mets OM, Muller NL, Bilawich AM. Chronic Lung Allograft Dysfunction: Review of CT and Pathologic Findings. Radiol Cardiothorac Imaging 2021; 3:e200314. [PMID: 33778654 PMCID: PMC7978021 DOI: 10.1148/ryct.2021200314] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 11/02/2020] [Accepted: 11/06/2020] [Indexed: 04/14/2023]
Abstract
Chronic lung allograft dysfunction (CLAD) is the most common cause of mortality in lung transplant recipients after the 1st year of transplantation. CLAD has traditionally been classified into two distinct obstructive and restrictive forms: bronchiolitis obliterans syndrome and restrictive allograft syndrome. However, CLAD may manifest with a spectrum of imaging and pathologic findings and a combination of obstructive and restrictive physiologic abnormalities. Although the initial CT manifestations of CLAD may be nonspecific, the progression of findings at follow-up should signal the possibility of CLAD and may be present on imaging studies prior to the development of functional abnormalities of the lung allograft. This review encompasses the evolution of CT findings in CLAD, with emphasis on the underlying pathogenesis and pathologic condition, to enhance understanding of imaging findings. The purpose of this article is to familiarize the radiologist with the initial and follow-up CT findings of the obstructive, restrictive, and mixed forms of CLAD, for which early diagnosis and treatment may result in improved survival. Supplemental material is available for this article. © RSNA, 2021.
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27
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Nascimento DZ, Watte G, Torres FS, Schio SM, Sanchez L, de Sousa JLM, Perin FA, Verma N, Mohammed TLH, Hochhegger B. Utilization of Quantitative Computed Tomography Assessment to Identify Bronchiolitis Obliterans Syndrome After Single Lung Transplantation. Lung 2021; 199:29-35. [PMID: 33439337 DOI: 10.1007/s00408-020-00417-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/24/2020] [Indexed: 10/22/2022]
Abstract
OBJECTIVE To evaluate quantitative chest computed tomography (CT) methods for the detection of air trapping (AT) and to assess its diagnostic performance for the diagnosis of bronchiolitis obliterans syndrome (BOS) in single lung transplant (SLT) patients. METHODS Adult patients who had a SLT at a single transplant center and underwent CT scan after transplantation were retrospectively included. CT findings of air trapping were measured by three different methods: expiratory air-trapping index (ATIexp), mean lung density on expiratory acquisition (MLDexp) and expiratory to inspiratory ratio of mean lung density (E/I-ratio(MLD). Sensitivity, specificity and diagnostic accuracy of the three methods for the detection of BOS status evaluated by serial routine measures of pulmonary function tests (gold standard) were assessed. RESULTS Forty-six SLT patients (52.2% females, mean age 58 ± 6 years) were included in the analysis, 12 (26%) patients with a diagnosis of BOS. Quantitative CT diagnosis of AT ranged from 26 to 35%. Sensitivity, specificity and accuracy of each method for the detection of BOS were 85.7%, 84.7% and 85.0% for ATIexp, 78.5%, 93.4% and 90.0% for MLD and 64.2%, 89.1% and 83.3% E/I-ratio(MLD), respectively. CONCLUSION Quantitative measures of AT obtained from standard CT are feasible and show high specificity and accuracy for the detection of BOS in SLT patients.
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Affiliation(s)
- Douglas Zaione Nascimento
- Department of Lung Transplantation, Irmandade Santa Casa de Misericórdia de Porto Alegre, Av. Independência, 75, Porto Alegre, Brazil
| | - Guilherme Watte
- Medical Imaging Research Lab, LABIMED, Department of Radiology, Pavilhão Pereira Filho Hospital, Irmandade Santa Casa de Misericórdia de Porto Alegre, Av. Independência, 75, Porto Alegre, 90020160, Brazil.
| | - Felipe Soares Torres
- Joint Department of Medical Imaging, University of Toronto, 585 University Avenue, 1 PMB 274, Toronto, ON, M5G2N2, Canada
| | - Sadi Marcelo Schio
- Department of Lung Transplantation, Irmandade Santa Casa de Misericórdia de Porto Alegre, Av. Independência, 75, Porto Alegre, Brazil
| | - Leticia Sanchez
- Department of Lung Transplantation, Irmandade Santa Casa de Misericórdia de Porto Alegre, Av. Independência, 75, Porto Alegre, Brazil
| | - Jackeline Larissa Mendes de Sousa
- Department of Lung Transplantation, Irmandade Santa Casa de Misericórdia de Porto Alegre, Av. Independência, 75, Porto Alegre, Brazil
| | - Fabiola Adelia Perin
- Department of Lung Transplantation, Irmandade Santa Casa de Misericórdia de Porto Alegre, Av. Independência, 75, Porto Alegre, Brazil
| | - Nupur Verma
- Department of Radiology, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Tan-Lucien H Mohammed
- Department of Radiology, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Bruno Hochhegger
- Medical Imaging Research Lab, LABIMED, Department of Radiology, Pavilhão Pereira Filho Hospital, Irmandade Santa Casa de Misericórdia de Porto Alegre, Av. Independência, 75, Porto Alegre, 90020160, Brazil
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28
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Ross BD, Chenevert TL, Meyer CR. Retrospective Registration in Molecular Imaging. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00080-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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29
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Krings JG, Wenzel SE, Castro M. The emerging role of quantitative imaging in asthma. Br J Radiol 2020; 95:20201133. [PMID: 33242252 DOI: 10.1259/bjr.20201133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Quantitative imaging of the lung has proved to be a valuable tool that has improved our understanding of asthma. CT, MRI, and positron emission tomography have all been utilized in asthma with each modality having its own distinct advantages and disadvantages. Research has now demonstrated that quantitative imaging plays a valuable role in characterizing asthma phenotypes and endotypes, as well as potentially predicting future asthma morbidity. Nonetheless, future research is needed in order to minimize radiation exposure, standardize reporting, and further delineate how imaging can predict longitudinal outcomes. With future work, quantitative imaging may make its way into the clinical care of asthma and change our practice.
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Affiliation(s)
- James G Krings
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University in Saint Louis School of Medicine, Saint Louis, MO, USA
| | - Sally E Wenzel
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mario Castro
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, University of Kansas School of Medicine, Kansas City, KS, USA
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30
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Sharifi H, Lai YK, Guo H, Hoppenfeld M, Guenther ZD, Johnston L, Brondstetter T, Chhatwani L, Nicolls MR, Hsu JL. Machine Learning Algorithms to Differentiate Among Pulmonary Complications After Hematopoietic Cell Transplant. Chest 2020; 158:1090-1103. [PMID: 32343962 PMCID: PMC8097633 DOI: 10.1016/j.chest.2020.02.076] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 02/26/2020] [Accepted: 02/29/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Pulmonary complications, including infections, are highly prevalent in patients after hematopoietic cell transplantation with chronic graft-vs-host disease. These comorbid diseases can make the diagnosis of early lung graft-vs-host disease (bronchiolitis obliterans syndrome) challenging. A quantitative method to differentiate among these pulmonary diseases can address diagnostic challenges and facilitate earlier and more targeted therapy. STUDY DESIGN AND METHODS We conducted a single-center study of 66 patients with CT chest scans analyzed with a quantitative imaging tool known as parametric response mapping. Parametric response mapping results were correlated with pulmonary function tests and clinical characteristics. Five parametric response mapping metrics were applied to K-means clustering and support vector machine models to distinguish among posttransplantation lung complications solely from quantitative output. RESULTS Compared with parametric response mapping, spirometry showed a moderate correlation with radiographic air trapping, and total lung capacity and residual volume showed a strong correlation with radiographic lung volumes. K-means clustering analysis distinguished four unique clusters. Clusters 2 and 3 represented obstructive physiology (encompassing 81% of patients with bronchiolitis obliterans syndrome) in increasing severity (percentage air trapping 15.6% and 43.0%, respectively). Cluster 1 was dominated by normal lung, and cluster 4 was characterized by patients with parenchymal opacities. A support vector machine algorithm differentiated bronchiolitis obliterans syndrome with a specificity of 88%, sensitivity of 83%, accuracy of 86%, and an area under the receiver operating characteristic curve of 0.85. INTERPRETATION Our machine learning models offer a quantitative approach for the identification of bronchiolitis obliterans syndrome vs other lung diseases, including late pulmonary complications after hematopoietic cell transplantation.
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Affiliation(s)
- Husham Sharifi
- Department of Medicine, the Division of Pulmonary, Allergy, and Critical Care Medicine, Stanford University School of Medicine, Stanford, CA
| | - Yu Kuang Lai
- Department of Medicine, the Division of Pulmonary, Allergy, and Critical Care Medicine, Stanford University School of Medicine, Stanford, CA
| | - Henry Guo
- Departments of Radiology, Stanford University School of Medicine, Stanford, CA
| | - Mita Hoppenfeld
- Departments of Medicine, Stanford University School of Medicine, Stanford, CA
| | - Zachary D Guenther
- Departments of Radiology, Stanford University School of Medicine, Stanford, CA
| | - Laura Johnston
- Department of Medicine, Division of Blood and Marrow Transplantation, Stanford University School of Medicine, Stanford, CA
| | - Theresa Brondstetter
- Department of Medicine, the Division of Pulmonary, Allergy, and Critical Care Medicine, Stanford University School of Medicine, Stanford, CA
| | - Laveena Chhatwani
- Department of Medicine, the Division of Pulmonary, Allergy, and Critical Care Medicine, Stanford University School of Medicine, Stanford, CA
| | - Mark R Nicolls
- Department of Medicine, the Division of Pulmonary, Allergy, and Critical Care Medicine, Stanford University School of Medicine, Stanford, CA
| | - Joe L Hsu
- Department of Medicine, the Division of Pulmonary, Allergy, and Critical Care Medicine, Stanford University School of Medicine, Stanford, CA.
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31
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Levy L, Huszti E, Renaud-Picard B, Berra G, Kawashima M, Takahagi A, Fuchs E, Ghany R, Moshkelgosha S, Keshavjee S, Singer LG, Tikkanen J, Martinu T. Risk assessment of chronic lung allograft dysfunction phenotypes: Validation and proposed refinement of the 2019 International Society for Heart and Lung Transplantation classification system. J Heart Lung Transplant 2020; 39:761-770. [DOI: 10.1016/j.healun.2020.04.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 03/14/2020] [Accepted: 04/12/2020] [Indexed: 12/26/2022] Open
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32
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Cheng GS, Selwa KE, Hatt C, Ram S, Fortuna AB, Guerriero M, Himelhoch B, McAree D, Hoffman TC, Brisson J, Nazareno R, Bloye K, Johnson TD, Remberger M, Mattsson J, Vummidi D, Kazerooni EE, Lama VN, Galban S, Boeckh M, Yanik GA, Galban CJ. Multicenter evaluation of parametric response mapping as an indicator of bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation. Am J Transplant 2020; 20:2198-2205. [PMID: 32034974 PMCID: PMC7395854 DOI: 10.1111/ajt.15814] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 01/28/2020] [Accepted: 02/02/2020] [Indexed: 01/25/2023]
Abstract
Parametric response mapping (PRM) is a novel computed tomography (CT) technology that has shown potential for assessment of bronchiolitis obliterans syndrome (BOS) after hematopoietic stem cell transplantation (HCT). The primary aim of this study was to evaluate whether variations in image acquisition under real-world conditions affect the PRM measurements of clinically diagnosed BOS. CT scans were obtained retrospectively from 72 HCT recipients with BOS and graft-versus-host disease from Fred Hutchinson Cancer Research Center, Karolinska Institute, and the University of Michigan. Whole lung volumetric scans were performed at inspiration and expiration using site-specific acquisition and reconstruction protocols. PRM and pulmonary function measurements were assessed. Patients with moderately severe BOS at diagnosis (median forced expiratory volume at 1 second [FEV1] 53.5% predicted) had similar characteristics between sites. Variations in site-specific CT acquisition protocols had a negligible effect on the PRM-derived small airways disease (SAD), that is, BOS measurements. PRM-derived SAD was found to correlate with FEV1% predicted and FEV1/ forced vital capacity (R = -0.236, P = .046; and R = -0.689, P < .0001, respectively), which suggests that elevated levels in the PRM measurements are primarily affected by BOS airflow obstruction and not CT scan acquisition parameters. Based on these results, PRM may be applied broadly for post-HCT diagnosis and monitoring of BOS.
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Affiliation(s)
- Guang-Shing Cheng
- Clinical Research Division, Fred Hutchinson Cancer Research
Center, Seattle, Washington
| | | | | | - Sundaresh Ram
- Department of Radiology, Michigan Medicine, Ann Arbor,
Michigan
| | | | | | - Ben Himelhoch
- Michigan State University College of Human Medicine,
Lansing, Michigan
| | - Daniel McAree
- Pediatrics, University of Michigan, Ann Arbor,
Michigan
| | | | - Joseph Brisson
- Blood and Marrow Transplant Program, Michigan Medicine, Ann
Arbor, Michigan
| | - Ryan Nazareno
- Blood and Marrow Transplant Program, Michigan Medicine, Ann
Arbor, Michigan
| | - Kiernan Bloye
- Blood and Marrow Transplant Program, Michigan Medicine, Ann
Arbor, Michigan
| | - Timothy D. Johnson
- Department of Biostatistics, University of Michigan School
of Public Health, Ann Arbor, Michigan
| | - Mats Remberger
- Department of Oncology-Pathology, Karolinska University
Hospital, Stockholm, Sweden
| | - Jonas Mattsson
- Department of Oncology-Pathology, Karolinska University
Hospital, Stockholm, Sweden
| | | | | | - Vibha N. Lama
- Division of Pulmonary and Critical Care Medicine,
Michigan Medicine, Ann Arbor, Michigan
| | - Stefanie Galban
- Department of Radiology, Michigan Medicine, Ann Arbor,
Michigan
| | - Michael Boeckh
- Clinical Research Division, Fred Hutchinson Cancer Research
Center, Seattle, Washington
| | - Gregory A. Yanik
- Blood and Marrow Transplant Program, Michigan Medicine, Ann
Arbor, Michigan
| | - Craig J. Galban
- Department of Radiology, Michigan Medicine, Ann Arbor,
Michigan
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33
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Combs MP, Xia M, Wheeler DS, Belloli EA, Walker NM, Braeuer RR, Lyu DM, Murray S, Lama VN. Fibroproliferation in chronic lung allograft dysfunction: Association of mesenchymal cells in bronchoalveolar lavage with phenotypes and survival. J Heart Lung Transplant 2020; 39:815-823. [PMID: 32360292 DOI: 10.1016/j.healun.2020.04.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 04/06/2020] [Accepted: 04/13/2020] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Chronic lung allograft dysfunction (CLAD), the primary cause of poor outcome after lung transplantation, arises from fibrotic remodeling of the allograft and presents as diverse clinical phenotypes with variable courses. Here, we investigate whether bronchoalveolar lavage (BAL) mesenchymal cell activity at CLAD onset can inform regarding disease phenotype, progression, and survival. METHODS Mesenchymal cell colony-forming units (CFUs) were measured in BAL obtained at CLAD onset (n = 77) and CLAD-free time post-transplant matched controls (n = 77). CFU counts were compared using Wilcoxon's rank-sum test. Cox proportional hazards and restricted means models were utilized to investigate post-CLAD survival. RESULTS Higher mesenchymal CFU counts were noted in BAL at the time of CLAD onset than in CLAD-free controls. Patients with restrictive allograft syndrome had higher BAL mesenchymal CFU count at CLAD onset than patients with bronchiolitis obliterans syndrome (p = 0.011). Patients with high mesenchymal CFU counts (≥10) at CLAD onset had worse outcomes than those with low (<10) CFU counts, with shorter average survival (2.64 years vs 4.25 years; p = 0.027) and shorter progression-free survival, defined as time to developing either CLAD Stage 3 or death (0.97 years vs 2.70 years; p < 0.001). High CFU count remained predictive of decreased overall survival and progression-free survival after accounting for the CLAD phenotype and other clinical factors in multivariable analysis. CONCLUSIONS Fulminant fibroproliferation with higher mesenchymal CFU counts in BAL is noted in restrictive allograft syndrome and is independently associated with poor survival after CLAD onset.
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Affiliation(s)
- Michael P Combs
- Department of Internal Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Meng Xia
- Department of Biostatistics, University of Michigan, Ann Arbor, Michigan
| | - David S Wheeler
- Department of Internal Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Elizabeth A Belloli
- Department of Internal Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Natalie M Walker
- Department of Internal Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Russell R Braeuer
- Department of Internal Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Dennis M Lyu
- Department of Internal Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan
| | - Susan Murray
- Department of Biostatistics, University of Michigan, Ann Arbor, Michigan
| | - Vibha N Lama
- Department of Internal Medicine, Division of Pulmonary & Critical Care, University of Michigan, Ann Arbor, Michigan.
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MacNeil JL, Capaldi DPI, Westcott AR, Eddy RL, Barker AL, McCormack DG, Kirby M, Parraga G. Pulmonary Imaging Phenotypes of Chronic Obstructive Pulmonary Disease Using Multiparametric Response Maps. Radiology 2020; 295:227-236. [PMID: 32096708 DOI: 10.1148/radiol.2020191735] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Background Pulmonary imaging of chronic obstructive pulmonary disease (COPD) has focused on CT or MRI measurements, but these have not been evaluated in combination. Purpose To generate multiparametric response map (mPRM) measurements in ex-smokers with or without COPD by using volume-matched CT and hyperpolarized helium 3 (3He) MRI. Materials and Methods In this prospective study (https://clinicaltrials.gov, NCT02279329), participants underwent MRI and CT and completed pulmonary function tests, questionnaires, and the 6-minute walk test between December 2010 and January 2019. Disease status was determined by using Global initiative for chronic Obstructive Lung Disease (GOLD) criteria. The mPRM voxel values were generated by using co-registered MRI and CT labels. Kruskal-Wallis and Bonferroni tests were used to determine differences across disease severity, and correlations were determined by using Spearman coefficients. Results A total of 175 ex-smokers (mean age, 69 years ± 9 [standard deviation], 108 men) with or without COPD were evaluated. Ex-smokers without COPD had a larger fraction of normal mPRM voxels (60% vs 37%, 20%, and 7% for GOLD I, II, and III/IV disease, respectively; all P ≤ .001) and a smaller fraction of abnormal voxels, including small airways disease (normal CT, not ventilated: 5% vs 6% [not significant], 11%, and 19% [P ≤ .001 for both] for GOLD I, II, and III/IV disease, respectively) and mild emphysema (normal CT, abnormal apparent diffusion coefficient [ADC]: 33% vs 54%, 56%, and 54% for GOLD I, II, and III/IV disease respectively; all P ≤ .001). Normal mPRM measurements were positively correlated with forced expiratory volume in 1 second (FEV1) (r = 0.65, P < .001), the FEV1-to-forced vital capacity ratio (r = 0.81, P < .001), and diffusing capacity (r = 0.75, P < .001) and were negatively correlated with worse quality of life (r = -0.48, P < .001). Abnormal mPRM measurements of small airways disease (normal CT, not ventilated) and mild emphysema (normal CT, abnormal ADC) were negatively correlated with FEV1 (r = -0.65 and -0.42, respectively; P < .001) and diffusing capacity (r = -0.53 and -0.60, respectively; P < .001) and were positively correlated with worse quality of life (r = 0.45 and r = 0.33, respectively; P < .001), both of which were present in ex-smokers without COPD. Conclusion Multiparametric response maps revealed two abnormal structure-function results related to emphysema and small airways disease, both of which were unexpectedly present in ex-smokers with normal spirometry and CT findings. © RSNA, 2020 Online supplemental material is available for this article.
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Affiliation(s)
- Jonathan L MacNeil
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
| | - Dante P I Capaldi
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
| | - Andrew R Westcott
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
| | - Rachel L Eddy
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
| | - Andrea L Barker
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
| | - David G McCormack
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
| | - Miranda Kirby
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
| | - Grace Parraga
- From the Robarts Research Institute (J.L.M., A.R.W., R.L.E., A.L.B., G.P.), School of Biomedical Engineering (J.L.M., G.P.), Department of Medical Biophysics (A.R.W., R.L.E., A.L.B., G.P.), and Division of Respirology, Department of Medicine (D.G.M., G.P.), Western University, 1151 Richmond St N, London, ON, Canada N6A 5B7; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, Calif (D.P.I.C.); and Department of Physics, Ryerson University, Toronto, Ontario, Canada (M.K.)
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Postinfectious Bronchiolitis Obliterans in Children: Diagnostic Workup and Therapeutic Options: A Workshop Report. Can Respir J 2020; 2020:5852827. [PMID: 32076469 PMCID: PMC7013295 DOI: 10.1155/2020/5852827] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/29/2019] [Accepted: 12/27/2019] [Indexed: 12/23/2022] Open
Abstract
Bronchiolitis obliterans (BO) is a rare, chronic form of obstructive lung disease, often initiated with injury of the bronchiolar epithelium followed by an inflammatory response and progressive fibrosis of small airways resulting in nonuniform luminal obliteration or narrowing. The term BO comprises a group of diseases with different underlying etiologies, courses, and characteristics. Among the better recognized inciting stimuli leading to BO are airway pathogens such as adenovirus and mycoplasma, which, in a small percentage of infected children, will result in progressive fixed airflow obstruction, an entity referred to as postinfectious bronchiolitis obliterans (PIBO). The present knowledge on BO in general is reasonably well developed, in part because of the relatively high incidence in patients who have undergone lung transplantation or bone marrow transplant recipients who have had graft-versus-host disease in the posttransplant period. The cellular and molecular pathways involved in PIBO, while assumed to be similar, have not been adequately elucidated. Since 2016, an international consortium of experts with an interest in PIBO assembles on a regular basis in Geisenheim, Germany, to discuss key areas in PIBO which include diagnostic workup, treatment strategies, and research fields.
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36
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Lung Transplantation for Cystic Fibrosis. Respir Med 2020. [DOI: 10.1007/978-3-030-42382-7_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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37
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Lung Density Analysis Using Quantitative Chest CT for Early Prediction of Chronic Lung Allograft Dysfunction. Transplantation 2019; 103:2645-2653. [DOI: 10.1097/tp.0000000000002771] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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38
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Weinheimer O, Hoff BA, Fortuna AB, Fernández-Baldera A, Konietzke P, Wielpütz MO, Robinson TE, Galbán CJ. Influence of Inspiratory/Expiratory CT Registration on Quantitative Air Trapping. Acad Radiol 2019; 26:1202-1214. [PMID: 30545681 DOI: 10.1016/j.acra.2018.11.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/25/2018] [Accepted: 11/03/2018] [Indexed: 12/21/2022]
Abstract
RATIONALE AND OBJECTIVES The aim of this study was to assess variability in quantitative air trapping (QAT) measurements derived from spatially aligned expiration CT scans. MATERIALS AND METHODS Sixty-four paired CT examinations, from 16 school-age cystic fibrosis subjects examined at four separate time intervals, were used in this study. For each pair, visually inspected lobe segmentation maps were generated and expiration CT data were registered to the inspiration CT frame. Measurements of QAT, the percentage of voxels on the expiration CT scan below a set threshold were calculated for each lobe and whole-lung from the registered expiration CT and compared to the true values from the unregistered data. RESULTS A mathematical model, which simulates the effect of variable regions of lung deformation on QAT values calculated from aligned to those from unaligned data, showed the potential for large bias. Assessment of experimental QAT measurements using Bland-Altman plots corroborated the model simulations, demonstrating biases greater than 5% when QAT was approximately 40% of lung volume. These biases were removed when calculating QAT from aligned expiration CT data using the determinant of the Jacobian matrix. We found, by Dice coefficient analysis, good agreement between aligned expiration and inspiration segmentation maps for the whole-lung and all but one lobe (Dice coefficient > 0.9), with only the lingula generating a value below 0.9 (mean and standard deviation of 0.85 ± 0.06). CONCLUSION The subtle and predictable variability in corrected QAT observed in this study suggests that image registration is reliable in preserving the accuracy of the quantitative metrics.
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Affiliation(s)
- Oliver Weinheimer
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; Translational Lung Research Center, Heidelberg (TLRC), German Lung Research Center (DZL), 69120 Heidelberg, Germany
| | - Benjamin A Hoff
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109
| | - Aleksa B Fortuna
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109
| | | | - Philip Konietzke
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; Translational Lung Research Center, Heidelberg (TLRC), German Lung Research Center (DZL), 69120 Heidelberg, Germany
| | - Mark O Wielpütz
- Department of Diagnostic and Interventional Radiology, University Hospital of Heidelberg, 69120 Heidelberg, Germany; Translational Lung Research Center, Heidelberg (TLRC), German Lung Research Center (DZL), 69120 Heidelberg, Germany
| | - Terry E Robinson
- Center of Excellence in Pulmonary Biology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94304
| | - Craig J Galbán
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109.
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Tissot A, Danger R, Claustre J, Magnan A, Brouard S. Early Identification of Chronic Lung Allograft Dysfunction: The Need of Biomarkers. Front Immunol 2019; 10:1681. [PMID: 31379869 PMCID: PMC6650588 DOI: 10.3389/fimmu.2019.01681] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 07/04/2019] [Indexed: 01/12/2023] Open
Abstract
A growing number of patients with end-stage lung disease have benefited from lung transplantation (LT). Improvements in organ procurement, surgical techniques and intensive care management have greatly increased short-term graft survival. However, long-term outcomes remain limited, mainly due to the onset of chronic lung allograft dysfunction (CLAD), whose diagnosis is based on permanent loss of lung function after the development of irreversible lung lesions. CLAD is associated with high mortality and morbidity, and its exact physiopathology is still only partially understood. Many researchers and clinicians have searched for CLAD biomarkers to improve diagnosis, to refine the phenotypes associated with differential prognosis and to identify early biological processes that lead to CLAD to enable an early intervention that could modify the inevitable degradation of respiratory function. Donor-specific antibodies are currently the only biomarkers used in routine clinical practice, and their significance for accurately predicting CLAD is still debated. We describe here significant studies that have highlighted potential candidates for reliable and non-invasive biomarkers of CLAD in the fields of imaging and functional monitoring, humoral immunity, cell-mediated immunity, allograft injury, airway remodeling and gene expression. Such biomarkers would improve CLAD prediction and allow differential LT management regarding CLAD risk.
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Affiliation(s)
- Adrien Tissot
- Centre de Recherche en Transplantation et Immunologie (CRTI), INSERM, Université de Nantes, Nantes, France.,Service de Pneumologie, Institut du Thorax, CHU Nantes, Nantes, France
| | - Richard Danger
- Centre de Recherche en Transplantation et Immunologie (CRTI), INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France
| | - Johanna Claustre
- Centre de Recherche en Transplantation et Immunologie (CRTI), INSERM, Université de Nantes, Nantes, France.,Service Hospitalo-Universitaire de Pneumologie - Physiologie, CHU Grenoble Alpes, Grenoble, France
| | - Antoine Magnan
- Centre de Recherche en Transplantation et Immunologie (CRTI), INSERM, Université de Nantes, Nantes, France.,Service de Pneumologie, Institut du Thorax, CHU Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France.,UMR S 1087 CNRS UMR 6291, Institut du Thorax, CHU Nantes, Université de Nantes, Nantes, France
| | - Sophie Brouard
- Centre de Recherche en Transplantation et Immunologie (CRTI), INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France
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40
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Moher Alsady T, Voskrebenzev A, Greer M, Becker L, Kaireit TF, Welte T, Wacker F, Gottlieb J, Vogel-Claussen J. MRI-derived regional flow-volume loop parameters detect early-stage chronic lung allograft dysfunction. J Magn Reson Imaging 2019; 50:1873-1882. [PMID: 31134705 DOI: 10.1002/jmri.26799] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Chronic lung allograft dysfunction (CLAD) is a major cause for the low long-term survival rates after lung transplantation (LTx). Early detection of CLAD may enable providing medical treatment before a nonreversible graft dysfunction has occurred. MRI is advantageous to pulmonary function testing (PFT) in the ability to assess regional function changes, and thus have the potential in detecting very early stages of CLAD before changes in global forced expiratory volume during the first second (FEV1%) occur. PURPOSE To examine whether early stages of CLAD (diagnosed based on PFT values) could also be detected using MRI-derived parameters of regional flow-volume dynamics. STUDY TYPE Retrospective. POPULATION 62 lung transplantation recipients were included in the study, 29 of which had been diagnosed with CLAD at various stages. FIELD STRENGTH/SEQUENCE MRI datasets were acquired with a 1.5T Siemens scanner using a spoiled gradient echo sequence. ASSESSMENT MRI datasets were retrospectively preprocessed and analyzed by a blinded radiologist according to the phase resolved functional lung MRI (PREFUL-MRI) approach, resulting in fractional ventilation (FV) maps and regional flow-volume loops (rFVL). FV- and rFVL-based parameters of regional lung ventilation were estimated. STATISTICAL TESTS Differences between groups were compared by Mann-Whitney U-test with a Bonferroni correction for multiple comparisons (n = 2). RESULTS rFVL-CC-based parameters discriminated significantly between the presence or absence of CLAD (P < 0.003). DATA CONCLUSION Using the contrast media-free PREFUL-MRI technique, parameters of ventilation dynamics and its regional heterogeneity were shown to be sensitive for the detection of early CLAD stages. LEVEL OF EVIDENCE 3 TECHNICAL EFFICACY: Stage 3 J. Magn. Reson. Imaging 2019;50:1873-1882.
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Affiliation(s)
- Tawfik Moher Alsady
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany
| | - Andreas Voskrebenzev
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany
| | - Mark Greer
- German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany.,Department of Respiratory Medicine, Hanover Medical School, Hanover, Germany
| | - Lena Becker
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany
| | - Till F Kaireit
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany
| | - Tobias Welte
- German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany.,Department of Respiratory Medicine, Hanover Medical School, Hanover, Germany
| | - Frank Wacker
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany
| | - Jens Gottlieb
- German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany.,Department of Respiratory Medicine, Hanover Medical School, Hanover, Germany
| | - Jens Vogel-Claussen
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,German Center for Lung Research, Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), Hanover, Germany
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Voskrebenzev A, Greer M, Gutberlet M, Schönfeld C, Renne J, Hinrichs J, Kaireit T, Welte T, Wacker F, Gottlieb J, Vogel-Claussen J. Detection of chronic lung allograft dysfunction using ventilation-weighted Fourier decomposition MRI. Am J Transplant 2018; 18:2050-2060. [PMID: 29607606 DOI: 10.1111/ajt.14759] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 03/04/2018] [Accepted: 03/25/2018] [Indexed: 01/25/2023]
Abstract
Chronic lung allograft dysfunction (CLAD) remains the leading cause of morbidity and mortality after lung transplantation. Diagnosis requires spirometric change, which becomes increasingly difficult with advancing CLAD. Fourier decomposition magnetic resonance imaging (FD-MRI) permits acquisition of ventilated-weighted images during free-breathing. This study evaluates FD-MRI in detecting CLAD in selected patients after bilateral lung transplantation (DLTx). DLTx recipients demonstrating CLAD at various stages participated. Radiologists remained blinded to clinical status until completion of image analysis. Image acquisition used a 1.5-T MR scanner using a spoiled gradient echo sequence. After FD processing and regional fractional ventilation (RFV) quantification, the volume defect percentage at 2 thresholds (VDP1,2 ), median lung RFV and quartile coefficient of dispersion (QCD) were calculated. Sixty-two patients participated. CLAD was present in 29/62 (47%) patients, of whom 17/62 (27%) had forced expiratory volume in 1 second ≤65% at image acquisition. VDP1 was higher among these participants compared to other groups (P < .001). Increased VDP1 was associated with subsequent graft loss, with values >2% showing reduced survival, independent of degree of graft dysfunction (P = .005). VDP2 discriminated between presence or absence of CLAD (area under the curve = 0.71; P = .03). QCD increased significantly with advancing disease (P < .001). In conclusion, FD-MRI-derived parameters demonstrate potential in quantitative CLAD diagnosis and assessment after DLTx.
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Affiliation(s)
- A Voskrebenzev
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - M Greer
- Department of Respiratory Medicine, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - M Gutberlet
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - C Schönfeld
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - J Renne
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - J Hinrichs
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - T Kaireit
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - T Welte
- Department of Respiratory Medicine, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - F Wacker
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - J Gottlieb
- Department of Respiratory Medicine, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
| | - J Vogel-Claussen
- Institute of Diagnostic and Interventional Radiology, Hanover Medical School, Hanover, Germany.,Biomedical Research in End-Stage and Obstructive Lung Disease (BREATH), German Center for Lung Research, Hanover, Germany
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42
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Dettmer S, Suhling H, Klingenberg I, Otten O, Kaireit T, Fuge J, Kuhnigk JM, Gottlieb J, Haverich A, Welte T, Wacker F, Vogel-Claussen J, Shin HO. Lobe-wise assessment of lung volume and density distribution in lung transplant patients and value for early detection of bronchiolitis obliterans syndrome. Eur J Radiol 2018; 106:137-144. [PMID: 30150035 DOI: 10.1016/j.ejrad.2018.07.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 06/04/2018] [Accepted: 07/18/2018] [Indexed: 02/07/2023]
Abstract
PURPOSE To evaluate quantitative computed tomography (CT) measurements of the lung parenchyma in lung transplant (LTx) patients for early detection of the bronchiolitis obliterans syndrome (BOS). MATERIALS AND METHODS 359 CT scans of 122 lung transplant patients were evaluated. Measurements of lung volume and density were performed for the whole lung and separately for each lobe. For longitudinal analysis the difference between the baseline at 6 months after LTx and follow-up examinations was calculated. Patients with and without BOS (matched 1:2) were compared at two different time points, the last examination before the BOS onset and the first examination within one year after BOS onset. RESULTS 30 patients developed BOS during the follow-up period. Longitudinal changes in the lung volume and lung density measured on CT differed significantly between those patients with and without early BOS, in particular the difference of the inspiratory and expiratory lung volume (p < 0.001), the ratio of the expiratory and inspiratory lung volume (p < 0.001-p = 0.001) and MLD (p < 0.001-p = 0.001), the volume on expiration (p < 0.001-p = 0.007), the MLD on expiration (p < 0.001-p = 0.007), and the percentiles on expiration (p < 0.001-p = 0.002) with an increase of lung volume and a decrease of lung density. Changes were pronounced in the lower lobes. Before BOS onset, patients with and without future development of BOS showed no significant differences. CONCLUSION Longitudinal changes of lung volume and lung density measured on CT start markedly at BOS onset with increased lung volume and decreased lung density indicating increased inflation levels. Even though this method may help to diagnose BOS at onset it is not useful as a predictor for BOS before disease onset.
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Affiliation(s)
- S Dettmer
- Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - H Suhling
- Department of Respiratory Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - I Klingenberg
- Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - O Otten
- Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - T Kaireit
- Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - J Fuge
- Department of Respiratory Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Germany.
| | - J M Kuhnigk
- Fraunhofer Institute for Medical Image Computing MEVIS, Augustenburger Platz 1, 13353 Berlin, Germany.
| | - J Gottlieb
- Department of Respiratory Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Germany.
| | - A Haverich
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Germany; Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - T Welte
- Department of Respiratory Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Germany.
| | - F Wacker
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Germany; Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - J Vogel-Claussen
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Germany; Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - H O Shin
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Germany; Department of Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
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Diagnosis and treatment of bronchiolitis obliterans syndrome accessible universally. Bone Marrow Transplant 2018; 54:383-392. [PMID: 30038355 DOI: 10.1038/s41409-018-0266-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 05/23/2018] [Accepted: 06/07/2018] [Indexed: 12/17/2022]
Abstract
The incidence of bronchiolitis obliterans syndrome (BOS), a devastating manifestation of chronic graft-versus-host-disease, may rise globally due to steady increases in utilization of allogeneic hematopoietic cell transplantation (HCT). Though some advances have occurred in the past decade regarding understanding of the pathogenesis, diagnosis and treatment of BOS, the overall mortality and morbidity remain very high. We sought to determine the current diagnostic and therapeutic challenges, which can potentially hinder optimal management of BOS both in developed and developing countries. We performed a comprehensive systematic review of both modern diagnostic modalities and treatments and then assessed which of them would be universally accessible. The 2014 National Institutes of Health chronic GVHD criteria remains the gold standard tool for diagnosing BOS. Important elements of treatment involve early and accurate detection, as well as utilizing the treatment modalities with known (but variable efficacy) e.g. fluticasone-azithromycin-montelukast [FAM] combination, etanercept, extra-corporeal photopheresis [ECP], lung transplantation, and prompt treatment of complications including infections in sufferers of BOS. Our results indicate that optimum diagnostic tools are not readily available in some parts of the world for early detection, which include a lack of CT scanners, unavailability of pulmonary function testing tools, absence of sub-specialists, lack of certain effective treatments and late referral for lung transplant. We present a systematic review of current literature along with recommendations for available therapies to guide practitioners to optimize the long-term outcomes in HCT survivors regardless of access to experts and expensive therapies.
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Horie M, Salazar P, Saito T, Binnie M, Brock K, Yasufuku K, Azad S, Keshavjee S, Martinu T, Paul N. Quantitative chest CT for subtyping chronic lung allograft dysfunction and its association with survival. Clin Transplant 2018; 32:e13233. [DOI: 10.1111/ctr.13233] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Miho Horie
- Joint Department of Medical Imaging; University Health Network; University of Toronto; Toronto ON Canada
- Institute for Biomaterials and Biomedical Engineering; University of Toronto; Toronto ON Canada
| | | | - Tomohito Saito
- Latner Thoracic Surgery Research Laboratories; Toronto General Research Institute; University Health Network; University of Toronto; Toronto ON Canada
- Toronto Lung Transplant Program; University Health Network; University of Toronto; Toronto ON Canada
- Department of Thoracic Surgery; Kansai Medical University; Hirakata Japan
| | - Matthew Binnie
- Toronto Lung Transplant Program; University Health Network; University of Toronto; Toronto ON Canada
| | - Kristy Brock
- Department of Imaging Physics; The University of Texas M.D. Anderson Cancer Center; Houston TX USA
| | - Kazuhiro Yasufuku
- Latner Thoracic Surgery Research Laboratories; Toronto General Research Institute; University Health Network; University of Toronto; Toronto ON Canada
- Toronto Lung Transplant Program; University Health Network; University of Toronto; Toronto ON Canada
| | - Sassan Azad
- Latner Thoracic Surgery Research Laboratories; Toronto General Research Institute; University Health Network; University of Toronto; Toronto ON Canada
| | - Shaf Keshavjee
- Institute for Biomaterials and Biomedical Engineering; University of Toronto; Toronto ON Canada
- Toronto Lung Transplant Program; University Health Network; University of Toronto; Toronto ON Canada
- Department of Thoracic Surgery; Kansai Medical University; Hirakata Japan
| | - Tereza Martinu
- Toronto Lung Transplant Program; University Health Network; University of Toronto; Toronto ON Canada
| | - Narinder Paul
- Joint Department of Medical Imaging; University Health Network; University of Toronto; Toronto ON Canada
- Institute for Biomaterials and Biomedical Engineering; University of Toronto; Toronto ON Canada
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Silva M, Milanese G, Seletti V, Ariani A, Sverzellati N. Pulmonary quantitative CT imaging in focal and diffuse disease: current research and clinical applications. Br J Radiol 2018; 91:20170644. [PMID: 29172671 PMCID: PMC5965469 DOI: 10.1259/bjr.20170644] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 11/14/2017] [Accepted: 11/23/2017] [Indexed: 12/14/2022] Open
Abstract
The frenetic development of imaging technology-both hardware and software-provides exceptional potential for investigation of the lung. In the last two decades, CT was exploited for detailed characterization of pulmonary structures and description of respiratory disease. The introduction of volumetric acquisition allowed increasingly sophisticated analysis of CT data by means of computerized algorithm, namely quantitative CT (QCT). Hundreds of thousands of CTs have been analysed for characterization of focal and diffuse disease of the lung. Several QCT metrics were developed and tested against clinical, functional and prognostic descriptors. Computer-aided detection of nodules, textural analysis of focal lesions, densitometric analysis and airway segmentation in obstructive pulmonary disease and textural analysis in interstitial lung disease are the major chapters of this discipline. The validation of QCT metrics for specific clinical and investigational needs prompted the translation of such metrics from research field to patient care. The present review summarizes the state of the art of QCT in both focal and diffuse lung disease, including a dedicated discussion about application of QCT metrics as parameters for clinical care and outcomes in clinical trials.
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Affiliation(s)
- Mario Silva
- Department of Medicine and Surgery (DiMeC), Section of Radiology, Unit of Surgical Sciences, University of Parma, Parma, Italy
| | - Gianluca Milanese
- Department of Medicine and Surgery (DiMeC), Section of Radiology, Unit of Surgical Sciences, University of Parma, Parma, Italy
| | - Valeria Seletti
- Department of Medicine and Surgery (DiMeC), Section of Radiology, Unit of Surgical Sciences, University of Parma, Parma, Italy
| | - Alarico Ariani
- Department of Medicine, Internal Medicine and Rheumatology Unit, University Hospital of Parma, Parma, Italy
| | - Nicola Sverzellati
- Department of Medicine and Surgery (DiMeC), Section of Radiology, Unit of Surgical Sciences, University of Parma, Parma, Italy
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Nyilas S, Carlens J, Price T, Singer F, Müller C, Hansen G, Warnecke G, Latzin P, Schwerk N. Multiple breath washout in pediatric patients after lung transplantation. Am J Transplant 2018; 18:145-153. [PMID: 28719135 DOI: 10.1111/ajt.14432] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/06/2017] [Accepted: 07/11/2017] [Indexed: 01/25/2023]
Abstract
Forced expiratory volume in 1 second (FEV1 ) from spirometry is the most commonly used parameter to detect early allograft dysfunction after lung transplantation (LTx). There are concerns regarding its sensitivity. Nitrogen-multiple breath washout (N2 -MBW) is sensitive at detecting early global (lung clearance index [LCI]) and acinar (Sacin ) airway inhomogeneity. We investigated whether N2 -MBW indices indicate small airways pathology after LTx in children with stable spirometry. Thirty-seven children without bronchiolitis obliterans syndrome [BOS] at a median of 1.6 (0.6-3.0) years after LTx underwent N2 -MBW and spirometry, 28 of those on 2 occasions (≤6 months apart) during clinically stable periods. Additional longitudinal data (11 and 8 measurements, respectively) are provided from 2 patients with BOS. In patients without BOS, LCI and Sacin were significantly elevated compared with healthy controls. LCI was abnormal at the 2 test occasions in 81% and 71% of patients, respectively, compared with 30% and 39% of patients with abnormal FEV1 /forced vital capacity (FVC). Correlations of LCI with FEV1 /FVC (r = 0.1, P = .4) and FEV1 (r = -0.1, P = .6) were poor. N2 -MBW represents a sensitive and reproducible tool for the early detection of airways pathology in stable transplant recipients. Moreover, indices were highly elevated in both patients with BOS. Spirometry and LCI showed poor correlation, indicating distinct and complementary physiologic measures.
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Affiliation(s)
- S Nyilas
- Paediatric Respiratory Medicine, Department of Paediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - J Carlens
- Department of Paediatric Pulmonology, Allergology and Neonatology, University Children`s Hospital Hannover, Hannover, Germany
| | - T Price
- Department of Paediatric Pulmonology, Allergology and Neonatology, University Children`s Hospital Hannover, Hannover, Germany
| | - F Singer
- Paediatric Respiratory Medicine, Department of Paediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Division of Paediatric Pneumology, University Children's Hospital Zurich, Zurich, Switzerland
| | - C Müller
- Department of Paediatric Pulmonology, Allergology and Neonatology, University Children`s Hospital Hannover, Hannover, Germany
| | - G Hansen
- Department of Paediatric Pulmonology, Allergology and Neonatology, University Children`s Hospital Hannover, Hannover, Germany
| | - G Warnecke
- Department of Paediatric Pulmonology, Allergology and Neonatology, University Children`s Hospital Hannover, Hannover, Germany
| | - P Latzin
- Paediatric Respiratory Medicine, Department of Paediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - N Schwerk
- Department of Paediatric Pulmonology, Allergology and Neonatology, University Children`s Hospital Hannover, Hannover, Germany
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Nyilas S, Baumeler L, Tamm M, Halter JP, Savic S, Korten I, Meyer A, Singer F, Passweg JR, Latzin P, Stolz D. Inert Gas Washout in Bronchiolitis Obliterans Following Hematopoietic Cell Transplantation. Chest 2017; 154:157-168. [PMID: 29275133 DOI: 10.1016/j.chest.2017.12.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/27/2017] [Accepted: 12/01/2017] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Bronchiolitis obliterans syndrome (BOS) is a leading cause of chronic graft-vs-host disease (cGvHD) and is associated with mortality after allogeneic hematopoietic stem cell transplantation (alloHSCT). The nitrogen multiple breath washout test (N2-MBW) measures ventilation inhomogeneity, a biomarker of central and peripheral airway obstruction. The aim of this study was to examine ventilation inhomogeneity according to cGvHD score and histologically defined bronchiolitis obliterans (BO). METHODS This single-center prospective cross-sectional study included 225 adults (mean age, 52.8 years; median, 5.4 years [interquartile range, 2.0-11 years]) after alloHSCT. Outcomes were global (lung clearance index [LCI]) and acinar ventilation inhomogeneity index (SACIN) from N2-MBW. Patients were categorized into five groups: (1) no cGvHD and no obstruction (cGvHD overall score 0 and FEV1/FVC ≥ 70) (2) cGvHD and no obstruction (cGvHD overall score 1-3 and FEV1/FVC ≥ 70), (3) BOS with or without cGvHD (if available, no BO on histologic examination, and FEV1/FVC < 70), (4) histologically proven BO, and (5) diffuse parenchymal lung disease other than BO. RESULTS The LCI and SACIN differed significantly between groups (P < .001) and increased progressively according to cGvHD score. In BO, the LCI and SACIN were elevated in 95.5% and 81.8% of patients, respectively, whereas FEV1/FVC was abnormal in only 56.5% of patients, respectively. CONCLUSIONS N2-MBW is highly sensitive for detecting abnormal lung function in patients following alloHSCT. LCI and SACIN seem to be promising biomarkers of lung involvement in cGvHD.
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Affiliation(s)
- Sylvia Nyilas
- Division of Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, University of Bern, Bern, Switzerland; Department of Pediatric Pneumology, University Children's Hospital Basel, Switzerland
| | - Luzia Baumeler
- Clinic of Pulmonary Medicine and Respiratory Cell Research, University Hospital Basel, Basel, Switzerland
| | - Michael Tamm
- Clinic of Pulmonary Medicine and Respiratory Cell Research, University Hospital Basel, Basel, Switzerland
| | - Jörg P Halter
- Division of Hematology, University Hospital Basel, Basel, Switzerland
| | - Spasenija Savic
- Institute of Pathology, University Hospital Basel, Basel, Switzerland
| | - Insa Korten
- Division of Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, University of Bern, Bern, Switzerland
| | - Anja Meyer
- Clinic of Pulmonary Medicine and Respiratory Cell Research, University Hospital Basel, Basel, Switzerland
| | - Florian Singer
- Division of Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, University of Bern, Bern, Switzerland
| | - Jakob R Passweg
- Division of Hematology, University Hospital Basel, Basel, Switzerland
| | - Philipp Latzin
- Division of Pediatric Respiratory Medicine, Department of Pediatrics, Inselspital, University of Bern, Bern, Switzerland; Department of Pediatric Pneumology, University Children's Hospital Basel, Switzerland
| | - Daiana Stolz
- Clinic of Pulmonary Medicine and Respiratory Cell Research, University Hospital Basel, Basel, Switzerland.
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48
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Abstract
Chronic lung allograft dysfunction (CLAD) is the major limitation to posttransplant survival. This review highlights the evolving definition of CLAD, risk factors, treatment, and expected outcomes after the development of CLAD.
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49
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Bergeron A, Cheng GS. Bronchiolitis Obliterans Syndrome and Other Late Pulmonary Complications After Allogeneic Hematopoietic Stem Cell Transplantation. Clin Chest Med 2017; 38:607-621. [PMID: 29128013 DOI: 10.1016/j.ccm.2017.07.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
As more individuals survive their hematologic malignancies after allogeneic hematopoietic stem cell transplantation (HSCT), there is growing appreciation of the late organ complications of this curative procedure for malignant and nonmalignant hematologic disorders. Late noninfectious pulmonary complications encompass all aspects of the bronchopulmonary anatomy. There have been recent advances in the diagnostic recognition and management of bronchiolitis obliterans syndrome, which is recognized as a pulmonary manifestation of chronic graft-versus-host disease. Organizing pneumonia and other interstitial lung diseases are increasingly recognized. This article provides an update on these entities as well as pleural and pulmonary vascular disease after allogeneic HSCT.
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Affiliation(s)
- Anne Bergeron
- Service de Pneumologie, AP-HP, Hôpital Saint-Louis, 1 Avenue Claude Vellefaux, 75010 Paris, France; Univ Paris Diderot, Sorbonne Paris Cité, UMR 1153 CRESS, Biostatistics and Clinical Epidemiology Research Team, Paris F-75010, France.
| | - Guang-Shing Cheng
- Clinical Research Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, D5-360, Seattle, WA 98105, USA; Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Washington School of Medicine, 1959 NE Pacific, Campus Box 356522, Seattle, WA 98195-6522, USA
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50
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Fernández-Baldera A, Hatt CR, Murray S, Hoffman EA, Kazerooni EA, Martinez FJ, Han MK, Galbán CJ. Correcting Nonpathological Variation in Longitudinal Parametric Response Maps of CT Scans in COPD Subjects: SPIROMICS. Tomography 2017; 3:138-145. [PMID: 29457137 PMCID: PMC5812694 DOI: 10.18383/j.tom.2017.00013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Small airways disease (SAD) is one of the leading causes of airflow limitations in patients diagnosed with chronic obstructive pulmonary disease (COPD). Parametric response mapping (PRM) of computed tomography (CT) scans allows for the quantification of this previously invisible COPD component. Although PRM is being investigated as a diagnostic tool for COPD, variability in the longitudinal measurements of SAD by PRM has been reported. Here, we show a method for correcting longitudinal PRM data because of non-pathological variations in serial CT scans. In this study, serial whole-lung high-resolution CT scans over a 30-day interval were obtained from 90 subjects with and without COPD accrued as part of SPIROMICS. It was assumed in all subjects that the COPD did not progress between examinations. CT scans were acquired at inspiration and expiration, spatially aligned to a single geometric frame, and analyzed using PRM. By modeling variability in longitudinal CT scans, our method could identify, at the voxel-level, shifts in PRM classification over the 30-day interval. In the absence of any correction, PRM generated serial percent volumes of functional SAD with differences as high as 15%. Applying the correction strategy significantly mitigated this effect with differences ~1%. At the voxel-level, significant differences were found between baseline PRM classifications and the follow-up map computed with and without correction (P <. 01 over GOLD). This strategy of accounting for nonpathological sources of variability in longitudinal PRM may improve the quantification of COPD phenotypes transitioning with disease progression.
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Affiliation(s)
| | | | - Susan Murray
- Department of Public Health, University of Michigan, Ann Arbor, MI
| | - Eric A. Hoffman
- Departments of Radiology and Biomedical Engineering, University of Iowa, IA
| | | | | | - MeiLan K. Han
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI
| | - Craig J. Galbán
- Department of Radiology, University of Michigan, Ann Arbor, MI
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