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Man F, Tang J, Swedrowska M, Forbes B, T M de Rosales R. Imaging drug delivery to the lungs: Methods and applications in oncology. Adv Drug Deliv Rev 2023; 192:114641. [PMID: 36509173 PMCID: PMC10227194 DOI: 10.1016/j.addr.2022.114641] [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: 08/31/2022] [Revised: 11/25/2022] [Accepted: 11/26/2022] [Indexed: 12/14/2022]
Abstract
Direct delivery to the lung via inhalation is arguably one of the most logical approaches to treat lung cancer using drugs. However, despite significant efforts and investment in this area, this strategy has not progressed in clinical trials. Imaging drug delivery is a powerful tool to understand and develop novel drug delivery strategies. In this review we focus on imaging studies of drug delivery by the inhalation route, to provide a broad overview of the field to date and attempt to better understand the complexities of this route of administration and the significant barriers that it faces, as well as its advantages. We start with a discussion of the specific challenges for drug delivery to the lung via inhalation. We focus on the barriers that have prevented progress of this approach in oncology, as well as the most recent developments in this area. This is followed by a comprehensive overview of the different imaging modalities that are relevant to lung drug delivery, including nuclear imaging, X-ray imaging, magnetic resonance imaging, optical imaging and mass spectrometry imaging. For each of these modalities, examples from the literature where these techniques have been explored are provided. Finally the different applications of these technologies in oncology are discussed, focusing separately on small molecules and nanomedicines. We hope that this comprehensive review will be informative to the field and will guide the future preclinical and clinical development of this promising drug delivery strategy to maximise its therapeutic potential.
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Affiliation(s)
- Francis Man
- School of Cancer & Pharmaceutical Sciences, King's College London, London, SE1 9NH, United Kingdom
| | - Jie Tang
- School of Biomedical Engineering & Imaging Sciences, King's College London, London SE1 7EH, United Kingdom
| | - Magda Swedrowska
- School of Cancer & Pharmaceutical Sciences, King's College London, London, SE1 9NH, United Kingdom
| | - Ben Forbes
- School of Cancer & Pharmaceutical Sciences, King's College London, London, SE1 9NH, United Kingdom
| | - Rafael T M de Rosales
- School of Biomedical Engineering & Imaging Sciences, King's College London, London SE1 7EH, United Kingdom.
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2
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Vliegenthart R, Fouras A, Jacobs C, Papanikolaou N. Innovations in thoracic imaging: CT, radiomics, AI and x-ray velocimetry. Respirology 2022; 27:818-833. [PMID: 35965430 PMCID: PMC9546393 DOI: 10.1111/resp.14344] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 07/08/2022] [Indexed: 12/11/2022]
Abstract
In recent years, pulmonary imaging has seen enormous progress, with the introduction, validation and implementation of new hardware and software. There is a general trend from mere visual evaluation of radiological images to quantification of abnormalities and biomarkers, and assessment of ‘non visual’ markers that contribute to establishing diagnosis or prognosis. Important catalysts to these developments in thoracic imaging include new indications (like computed tomography [CT] lung cancer screening) and the COVID‐19 pandemic. This review focuses on developments in CT, radiomics, artificial intelligence (AI) and x‐ray velocimetry for imaging of the lungs. Recent developments in CT include the potential for ultra‐low‐dose CT imaging for lung nodules, and the advent of a new generation of CT systems based on photon‐counting detector technology. Radiomics has demonstrated potential towards predictive and prognostic tasks particularly in lung cancer, previously not achievable by visual inspection by radiologists, exploiting high dimensional patterns (mostly texture related) on medical imaging data. Deep learning technology has revolutionized the field of AI and as a result, performance of AI algorithms is approaching human performance for an increasing number of specific tasks. X‐ray velocimetry integrates x‐ray (fluoroscopic) imaging with unique image processing to produce quantitative four dimensional measurement of lung tissue motion, and accurate calculations of lung ventilation. See relatedEditorial
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Affiliation(s)
- Rozemarijn Vliegenthart
- Department of Radiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.,Data Science in Health (DASH), University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | | | - Colin Jacobs
- Department of Medical Imaging, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Nickolas Papanikolaou
- Champalimaud Research, Champalimaud Foundation, Lisbon, Portugal.,AI Hub, The Royal Marsden NHS Foundation Trust, London, UK.,The Institute of Cancer Research, London, UK
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3
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Yang L, Gradl R, Dierolf M, Möller W, Kutschke D, Feuchtinger A, Hehn L, Donnelley M, Günther B, Achterhold K, Walch A, Stoeger T, Razansky D, Pfeiffer F, Morgan KS, Schmid O. Multimodal Precision Imaging of Pulmonary Nanoparticle Delivery in Mice: Dynamics of Application, Spatial Distribution, and Dosimetry. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1904112. [PMID: 31639283 DOI: 10.1002/smll.201904112] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 09/12/2019] [Indexed: 06/10/2023]
Abstract
Targeted delivery of nanomedicine/nanoparticles (NM/NPs) to the site of disease (e.g., the tumor or lung injury) is of vital importance for improved therapeutic efficacy. Multimodal imaging platforms provide powerful tools for monitoring delivery and tissue distribution of drugs and NM/NPs. This study introduces a preclinical imaging platform combining X-ray (two modes) and fluorescence imaging (three modes) techniques for time-resolved in vivo and spatially resolved ex vivo visualization of mouse lungs during pulmonary NP delivery. Liquid mixtures of iodine (contrast agent for X-ray) and/or (nano)particles (X-ray absorbing and/or fluorescent) are delivered to different regions of the lung via intratracheal instillation, nasal aspiration, and ventilator-assisted aerosol inhalation. It is demonstrated that in vivo propagation-based phase-contrast X-ray imaging elucidates the dynamic process of pulmonary NP delivery, while ex vivo fluorescence imaging (e.g., tissue-cleared light sheet fluorescence microscopy) reveals the quantitative 3D drug/particle distribution throughout the entire lung with cellular resolution. The novel and complementary information from this imaging platform unveils the dynamics and mechanisms of pulmonary NM/NP delivery and deposition for each of the delivery routes, which provides guidance on optimizing pulmonary delivery techniques and novel-designed NM for targeting and efficacy.
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Affiliation(s)
- Lin Yang
- Comprehensive Pneumology Center (CPC-M), Member of the German Center for Lung Research (DZL), Munich, 81377, Germany
- Institute of Lung Biology and Disease, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, 85764, Germany
- Faculty of Medicine, Technical University of Munich, Munich, 80333, Germany
| | - Regine Gradl
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Munich School of BioEngineering, Technical University of Munich, Garching, 85748, Germany
- Institute for Advanced Study, Technical University of Munich, Garching, 85748, Germany
| | - Martin Dierolf
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Munich School of BioEngineering, Technical University of Munich, Garching, 85748, Germany
| | - Winfried Möller
- Comprehensive Pneumology Center (CPC-M), Member of the German Center for Lung Research (DZL), Munich, 81377, Germany
- Institute of Lung Biology and Disease, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, 85764, Germany
| | - David Kutschke
- Comprehensive Pneumology Center (CPC-M), Member of the German Center for Lung Research (DZL), Munich, 81377, Germany
- Institute of Lung Biology and Disease, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, 85764, Germany
| | - Annette Feuchtinger
- Research Unit Analytical Pathology, Helmholtz Zentrum München, Neuherberg, 85764, Germany
| | - Lorenz Hehn
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technical University of Munich, München, 81675, Germany
| | - Martin Donnelley
- Robinson Research Institute and Adelaide Medical School, University of Adelaide, Adelaide, 5000, Australia
- Respiratory and Sleep Medicine, Women's and Children's Hospital, North Adelaide, SA, 5006, Australia
| | - Benedikt Günther
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Munich School of BioEngineering, Technical University of Munich, Garching, 85748, Germany
| | - Klaus Achterhold
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Munich School of BioEngineering, Technical University of Munich, Garching, 85748, Germany
| | - Axel Walch
- Research Unit Analytical Pathology, Helmholtz Zentrum München, Neuherberg, 85764, Germany
| | - Tobias Stoeger
- Comprehensive Pneumology Center (CPC-M), Member of the German Center for Lung Research (DZL), Munich, 81377, Germany
- Institute of Lung Biology and Disease, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, 85764, Germany
| | - Daniel Razansky
- Faculty of Medicine, Technical University of Munich, Munich, 80333, Germany
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Zentrum München, Neuherberg, 85764, Germany
- Faculty of Medicine and Institute of Pharmacology and Toxicology, University of Zurich, Zurich, CH-8057, Switzerland
- Institute for Biomedical Engineering and Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich, 8093, Switzerland
| | - Franz Pfeiffer
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Munich School of BioEngineering, Technical University of Munich, Garching, 85748, Germany
- Institute for Advanced Study, Technical University of Munich, Garching, 85748, Germany
- Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technical University of Munich, München, 81675, Germany
| | - Kaye S Morgan
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, Garching, 85748, Germany
- Institute for Advanced Study, Technical University of Munich, Garching, 85748, Germany
- School of Physics and Astronomy, Monash University, Clayton, Victoria, 3800, Australia
| | - Otmar Schmid
- Comprehensive Pneumology Center (CPC-M), Member of the German Center for Lung Research (DZL), Munich, 81377, Germany
- Institute of Lung Biology and Disease, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, 85764, Germany
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4
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In vivo Dynamic Phase-Contrast X-ray Imaging using a Compact Light Source. Sci Rep 2018; 8:6788. [PMID: 29717143 PMCID: PMC5931574 DOI: 10.1038/s41598-018-24763-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 04/05/2018] [Indexed: 12/14/2022] Open
Abstract
We describe the first dynamic and the first in vivo X-ray imaging studies successfully performed at a laser-undulator-based compact synchrotron light source. The X-ray properties of this source enable time-sequence propagation-based X-ray phase-contrast imaging. We focus here on non-invasive imaging for respiratory treatment development and physiological understanding. In small animals, we capture the regional delivery of respiratory treatment, and two measures of respiratory health that can reveal the effectiveness of a treatment; lung motion and mucociliary clearance. The results demonstrate the ability of this set-up to perform laboratory-based dynamic imaging, specifically in small animal models, and with the possibility of longitudinal studies.
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Galbusera A, De Felice A, Girardi S, Bassetto G, Maschietto M, Nishimori K, Chini B, Papaleo F, Vassanelli S, Gozzi A. Intranasal Oxytocin and Vasopressin Modulate Divergent Brainwide Functional Substrates. Neuropsychopharmacology 2017; 42:1420-1434. [PMID: 27995932 PMCID: PMC5436116 DOI: 10.1038/npp.2016.283] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 11/25/2016] [Accepted: 12/13/2016] [Indexed: 12/20/2022]
Abstract
The neuropeptides oxytocin (OXT) and vasopressin (AVP) have been identified as modulators of emotional social behaviors and associated with neuropsychiatric disorders characterized by social dysfunction. Experimental and therapeutic use of OXT and AVP via the intranasal route is the subject of extensive clinical research. However, the large-scale functional substrates directly engaged by these peptides and their functional dynamics remain elusive. By using cerebral blood volume (CBV) weighted fMRI in the mouse, we show that intranasal administration of OXT rapidly elicits the transient activation of cortical regions and a sustained activation of hippocampal and forebrain areas characterized by high oxytocin receptor density. By contrast, intranasal administration of AVP produced a robust and sustained deactivation in cortico-parietal, thalamic and mesolimbic regions. Importantly, intravenous administration of OXT and AVP did not recapitulate the patterns of modulation produced by intranasal dosing, supporting a central origin of the observed functional changes. In keeping with this notion, hippocampal local field potential recordings revealed multi-band power increases upon intranasal OXT administration. We also show that the selective OXT-derivative TGOT reproduced the pattern of activation elicited by OXT and that the deletion of OXT receptors does not affect AVP-mediated deactivation. Collectively, our data document divergent modulation of brainwide neural systems by intranasal administration of OXT and AVP, an effect that involves key substrates of social and emotional behavior. The observed divergence calls for a deeper investigation of the systems-level mechanisms by which exogenous OXT and AVP modulate brain function and exert their putative therapeutic effects.
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Affiliation(s)
- Alberto Galbusera
- Functional Neuroimaging Laboratory, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, Rovereto (TN), Italy
| | - Alessia De Felice
- Functional Neuroimaging Laboratory, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, Rovereto (TN), Italy
| | - Stefano Girardi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Giacomo Bassetto
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Marta Maschietto
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Katsuhiko Nishimori
- Laboratory of Molecular Biology, Department of Molecular and Cell Biology, Graduate School of Agricultural Science, Tohoku University, Miyagi, Japan
| | - Bice Chini
- CNR, Institute of Neuroscience, Milan, Italy,Department of Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Francesco Papaleo
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy
| | | | - Alessandro Gozzi
- Functional Neuroimaging Laboratory, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, Rovereto (TN), Italy,Functional Neuroimaging Laboratory, Center for Neuroscience and Cognitive Systems @UniTn, Istituto Italiano di Tecnologia, Rovereto (TN) 38068, Italy, Tel: +39 04648028701, E-mail:
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6
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Dubsky S, Fouras A. Imaging regional lung function: a critical tool for developing inhaled antimicrobial therapies. Adv Drug Deliv Rev 2015; 85:100-9. [PMID: 25819486 DOI: 10.1016/j.addr.2015.03.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 03/18/2015] [Accepted: 03/20/2015] [Indexed: 12/11/2022]
Abstract
Alterations in regional lung function due to respiratory infection have a significant effect on the deposition of inhaled treatments. This has consequences for treatment effectiveness and hence recovery of lung function. In order to advance our understanding of respiratory infection and inhaled treatment delivery, we must develop imaging techniques that can provide regional functional measurements of the lung. In this review, we explore the role of functional imaging for the assessment of respiratory infection and development of inhaled treatments. We describe established and emerging functional lung imaging methods. The effect of infection on lung function is described, and the link between regional disease, function, and inhaled treatments is discussed. The potential for lung function imaging to provide unique insights into the functional consequences of infection, and its treatment, is also discussed.
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Affiliation(s)
- Stephen Dubsky
- Department of Mechanical & Aerospace Engineering, Monash University, Victoria 3800, Australia.
| | - Andreas Fouras
- Department of Mechanical & Aerospace Engineering, Monash University, Victoria 3800, Australia.
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7
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Donnelley M, Morgan KS, Siu KKW, Fouras A, Farrow NR, Carnibella RP, Parsons DW. Tracking extended mucociliary transport activity of individual deposited particles: longitudinal synchrotron X-ray imaging in live mice. JOURNAL OF SYNCHROTRON RADIATION 2014; 21:768-773. [PMID: 24971973 DOI: 10.1107/s160057751400856x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 04/15/2014] [Indexed: 06/03/2023]
Abstract
To assess potential therapies for respiratory diseases in which mucociliary transit (MCT) is impaired, such as cystic fibrosis and primary ciliary dyskinesia, a novel and non-invasive MCT quantification method has been developed in which the transit rate and behaviour of individual micrometre-sized deposited particles are measured in live mice using synchrotron phase-contrast X-ray imaging. Particle clearance by MCT is known to be a two-phase process that occurs over a period of minutes to days. Previous studies have assessed MCT in the fast-clearance phase, ∼20 min after marker particle dosing. The aim of this study was to non-invasively image changes in particle presence and MCT during the slow-clearance phase, and simultaneously determine whether repeat synchrotron X-ray imaging of mice was feasible over periods of 3, 9 and 25 h. All mice tolerated the repeat imaging procedure with no adverse effects. Quantitative image analysis revealed that the particle MCT rate and the number of particles present in the airway both decreased with time. This study successfully demonstrated for the first time that longitudinal synchrotron X-ray imaging studies are possible in live small animals, provided appropriate animal handling techniques are used and care is taken to reduce the delivered radiation dose.
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Affiliation(s)
- Martin Donnelley
- Respiratory and Sleep Medicine, Women's and Children's Hospital, 72 King William Road, North Adelaide, SA 5006, Australia
| | - Kaye S Morgan
- School of Physics, Monash University, Clayton, Vic 3800, Australia
| | - Karen K W Siu
- School of Physics, Monash University, Clayton, Vic 3800, Australia
| | - Andreas Fouras
- Mechanical and Aerospace Engineering, Monash University, Clayton, Vic 3800, Australia
| | - Nigel R Farrow
- Respiratory and Sleep Medicine, Women's and Children's Hospital, 72 King William Road, North Adelaide, SA 5006, Australia
| | - Richard P Carnibella
- Mechanical and Aerospace Engineering, Monash University, Clayton, Vic 3800, Australia
| | - David W Parsons
- Respiratory and Sleep Medicine, Women's and Children's Hospital, 72 King William Road, North Adelaide, SA 5006, Australia
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8
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Non-invasive airway health assessment: synchrotron imaging reveals effects of rehydrating treatments on mucociliary transit in-vivo. Sci Rep 2014; 4:3689. [PMID: 24418935 PMCID: PMC3891397 DOI: 10.1038/srep03689] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 12/17/2013] [Indexed: 11/27/2022] Open
Abstract
To determine the efficacy of potential cystic fibrosis (CF) therapies we have developed a novel mucociliary transit (MCT) measurement that uses synchrotron phase contrast X-ray imaging (PCXI) to non-invasively measure the transit rate of individual micron-sized particles deposited into the airways of live mice. The aim of this study was to image changes in MCT produced by a rehydrating treatment based on hypertonic saline (HS), a current CF clinical treatment. Live mice received HS containing a long acting epithelial sodium channel blocker (P308); isotonic saline; or no treatment, using a nebuliser integrated within a small-animal ventilator circuit. Marker particle motion was tracked for 20 minutes using PCXI. There were statistically significant increases in MCT in the isotonic and HS-P308 groups. The ability to quantify in vivo changes in MCT may have utility in pre-clinical research studies designed to bring new genetic and pharmaceutical treatments for respiratory diseases into clinical trials.
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9
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Sera T, Yokota H, Tanaka G, Uesugi K, Yagi N, Schroter RC. Murine pulmonary acinar mechanics during quasi-static inflation using synchrotron refraction-enhanced computed tomography. J Appl Physiol (1985) 2013; 115:219-28. [PMID: 23661619 DOI: 10.1152/japplphysiol.01105.2012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We visualized pulmonary acini in the core regions of the mouse lung in situ using synchrotron refraction-enhanced computed tomography (CT) and evaluated their kinematics during quasi-static inflation. This CT system (with a cube voxel of 2.8 μm) allows excellent visualization of not just the conducting airways, but also the alveolar ducts and sacs, and tracking of the acinar shape and its deformation during inflation. The kinematics of individual alveoli and alveolar clusters with a group of terminal alveoli is influenced not only by the connecting alveolar duct and alveoli, but also by the neighboring structures. Acinar volume was not a linear function of lung volume. The alveolar duct diameter changed dramatically during inflation at low pressures and remained relatively constant above an airway pressure of ∼8 cmH2O during inflation. The ratio of acinar surface area to acinar volume indicates that acinar distension during low-pressure inflation differed from that during inflation over a higher pressure range; in particular, acinar deformation was accordion-like during low-pressure inflation. These results indicated that the alveoli and duct expand differently as total acinar volume increases and that the alveolar duct may expand predominantly during low-pressure inflation. Our findings suggest that acinar deformation in the core regions of the lung is complex and heterogeneous.
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Affiliation(s)
- Toshihiro Sera
- Center for Advanced Medical Engineering and Informatics, Osaka University, Osaka, Japan.
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Donnelley M, Morgan KS, Siu KKW, Parsons DW. Variability of in vivo fluid dose distribution in mouse airways is visualized by high-speed synchrotron X-ray imaging. J Aerosol Med Pulm Drug Deliv 2013; 26:307-16. [PMID: 23298238 DOI: 10.1089/jamp.2012.1007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The manner in which fluid instillations into mouse nose and lung distribute through the airways is poorly understood. Many agents are delivered in this way for testing as therapeutics, or as challenges designed to establish infections or create systemic drug delivery effects. These agents are delivered into mouse airways with little knowledge of the manner in which doses move through the airways, how long they reside in each region, and where the instilled materials eventually reach. METHODS Synchrotron phase-contrast X-ray imaging (PCXI) was used to elucidate the primary controlling characteristics of mouse airway fluid dosing. High-speed image acquisition was used to track the movement of a range of bolus doses of an iodine-based contrast fluid through the nose (n=15) and lungs (n=10) of live anesthetized mice. For the lung studies, the mice were ventilated and paralyzed to control animal movement. Post-experiment image processing was used to visualize the fluid movement. RESULTS The maximum dose that could be retained in only the anterior nose was ∼7.5 μL (20 g mouse), and a range of dynamic dose behaviors was documented after delivery. In the lung, the use of mechanical ventilation in combination with a paralytic agent prevented confounding artifactual movement, improving visualization of fluid progression through the airways. In the lung, optimized image analysis using the high image capture rate revealed the presence of respiratory pauses that could not be visualized at slower acquisition rates. The variability in the outcome of identical dose deliveries in different animals indicates that uniform lung distribution cannot be expected to occur with tracheal fluid delivery. CONCLUSIONS With adequate imaging rate and fluid dose parameters, this study shows the utility of synchrotron PCXI for determining the post-delivery behavior and fate of fluid doses such as those used in in vivo gene transfer or pharmaceutical studies.
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Affiliation(s)
- Martin Donnelley
- 1 Respiratory and Sleep Medicine, Women's and Children's Health Network , Adelaide, Australia
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11
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Donnelley M, Siu KKW, Jamison RA, Parsons DW. Synchrotron phase-contrast X-ray imaging reveals fluid dosing dynamics for gene transfer into mouse airways. Gene Ther 2011; 19:8-14. [PMID: 21654825 DOI: 10.1038/gt.2011.80] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although airway gene transfer research in mouse models relies on bolus fluid dosing into the nose or trachea, the dynamics and immediate fate of delivered gene transfer agents are poorly understood. In particular, this is because there are no in vivo methods able to accurately visualize the movement of fluid in small airways of intact animals. Using synchrotron phase-contrast X-ray imaging, we show that the fate of surrogate fluid doses delivered into live mouse airways can now be accurately and non-invasively monitored with high spatial and temporal resolution. This new imaging approach can help explain the non-homogenous distributions of gene expression observed in nasal airway gene transfer studies, suggests that substantial dose losses may occur at deliver into mouse trachea via immediate retrograde fluid motion and shows the influence of the speed of bolus delivery on the relative targeting of conducting and deeper lung airways. These findings provide insight into some of the factors that can influence gene expression in vivo, and this method provides a new approach to documenting and analyzing dose delivery in small-animal models.
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Affiliation(s)
- M Donnelley
- Department of Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, Australia.
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12
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Morgan KS, Paganin DM, Siu KKW. Quantitative x-ray phase-contrast imaging using a single grating of comparable pitch to sample feature size. OPTICS LETTERS 2011; 36:55-7. [PMID: 21209685 DOI: 10.1364/ol.36.000055] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The ability to quantitatively retrieve transverse phase maps during imaging by using coherent x rays often requires a precise grating or analyzer-crystal-based setup. Imaging of live animals presents further challenges when these methods require multiple exposures for image reconstruction. We present a simple method of single-exposure, single-grating quantitative phase contrast for a regime in which the grating period is much greater than the effective pixel size. A grating is used to create a high-visibility reference pattern incident on the sample, which is distorted according to the complex refractive index and thickness of the sample. The resolution, along a line parallel to the grating, is not restricted by the grating spacing, and the detector resolution becomes the primary determinant of the spatial resolution. We present a method of analysis that maps the displacement of interrogation windows in order to retrieve a quantitative phase map. Application of this analysis to the imaging of known phantoms shows excellent correspondence.
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Affiliation(s)
- Kaye S Morgan
- School of Physics, Monash University, Clayton, Victoria, Australia, 3800.
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