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Saengsin K, Sittiwangkul R, Borisuthipandit T, Wongyikul P, Tanasombatkul K, Phanacharoensawad T, Moonsawat G, Trongtrakul K, Phinyo P. Development of a clinical prediction tool for extubation failure in pediatric cardiac intensive care unit. Front Pediatr 2024; 12:1346198. [PMID: 38504995 PMCID: PMC10948403 DOI: 10.3389/fped.2024.1346198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/22/2024] [Indexed: 03/21/2024] Open
Abstract
Introduction/objective Extubation failure in pediatric patients with congenital or acquired heart diseases increases morbidity and mortality. This study aimed to develop a clinical risk score for predicting extubation failure to guide proper clinical decision-making and management. Methods We conducted a retrospective study. This clinical prediction score was developed using data from the Pediatric Cardiac Intensive Care Unit (PCICU) of the Faculty of Medicine, Chiang Mai University, Thailand, from July 2016 to May 2022. Extubation failure was defined as the requirement for re-intubation within 48 h after extubation. Multivariable logistic regression was used for modeling. The score was evaluated in terms of discrimination and calibration. Results A total of 352 extubation events from 270 patients were documented. Among these, 40 events (11.36%) were extubation failure. Factors associated with extubation failure included history of pneumonia (OR: 4.14, 95% CI: 1.83-9.37, p = 0.001), history of re-intubation (OR: 5.99, 95% CI: 2.12-16.98, p = 0.001), and high saturation in physiologic cyanosis (OR: 5.94, 95% CI: 1.87-18.84, p = 0.003). These three factors were utilized to develop the risk score. The score showed acceptable discrimination with an area under the curve (AUC) of 0.77 (95% CI: 0.69-0.86), and good calibration. Conclusion The derived Pediatric CMU Extubation Failure Prediction Score (Ped-CMU ExFPS) could satisfactorily predict extubation failure in pediatric cardiac patients. Employing this score could promote proper personalized care. We suggest conducting further external validation studies before considering implementation in practice.
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Affiliation(s)
- Kwannapas Saengsin
- Division of Cardiology, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center for Clinical Epidemiology and Clinical Statistics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Rekwan Sittiwangkul
- Division of Cardiology, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Thirasak Borisuthipandit
- Division of Pulmonology and Critical Care, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Pakpoom Wongyikul
- Center for Clinical Epidemiology and Clinical Statistics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Krittai Tanasombatkul
- Center for Clinical Epidemiology and Clinical Statistics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Department of Family Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | | | - Konlawij Trongtrakul
- Center for Clinical Epidemiology and Clinical Statistics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Division of Pulmonary, Critical Care Medicine, and Allergy, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Phichayut Phinyo
- Center for Clinical Epidemiology and Clinical Statistics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Department of Family Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
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2
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Wucherpfennig L, Kauczor HU, Eichinger M, Wielpütz MO. [Magnetic resonance imaging of the lung : State of the art]. RADIOLOGIE (HEIDELBERG, GERMANY) 2023; 63:849-862. [PMID: 37851088 DOI: 10.1007/s00117-023-01229-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/04/2023] [Indexed: 10/19/2023]
Abstract
Due to the low proton density of the lung parenchyma and the rapid signal decay at the air-tissue interfaces, for a long time the lungs were difficult to access using magnetic resonance imaging (MRI); however, technical advances could address most of these obstacles. Pulmonary alterations associated with tissue proliferation ("plus pathologies"), can now be detected with high diagnostic accuracy because of the locally increased proton density. Compared to computed tomography (CT), MRI provides a comprehensive range of functional imaging procedures (respiratory mechanics, perfusion and ventilation). In addition, as a radiation-free noninvasive examination modality, it enables repeated examinations for assessment of the course or monitoring of the effects of treatment, even in children. This article discusses the technical aspects, gives suggestions for protocols and explains the role of MRI of the lungs in the routine assessment of various diseases.
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Affiliation(s)
- Lena Wucherpfennig
- Klinik für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 420, 69120, Heidelberg, Deutschland
- Translational Lung Research Center Heidelberg (TLRC), Deutsches Zentrum für Lungenforschung (DZL), Im Neuenheimer Feld 130.3, 69120, Heidelberg, Deutschland
- Klinik für Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Thoraxklinik am Universitätsklinikum Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Deutschland
| | - Hans-Ulrich Kauczor
- Klinik für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 420, 69120, Heidelberg, Deutschland
- Translational Lung Research Center Heidelberg (TLRC), Deutsches Zentrum für Lungenforschung (DZL), Im Neuenheimer Feld 130.3, 69120, Heidelberg, Deutschland
- Klinik für Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Thoraxklinik am Universitätsklinikum Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Deutschland
| | - Monika Eichinger
- Klinik für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 420, 69120, Heidelberg, Deutschland
- Translational Lung Research Center Heidelberg (TLRC), Deutsches Zentrum für Lungenforschung (DZL), Im Neuenheimer Feld 130.3, 69120, Heidelberg, Deutschland
- Klinik für Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Thoraxklinik am Universitätsklinikum Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Deutschland
| | - Mark O Wielpütz
- Klinik für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 420, 69120, Heidelberg, Deutschland.
- Translational Lung Research Center Heidelberg (TLRC), Deutsches Zentrum für Lungenforschung (DZL), Im Neuenheimer Feld 130.3, 69120, Heidelberg, Deutschland.
- Klinik für Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Thoraxklinik am Universitätsklinikum Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Deutschland.
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Xu P, Meersmann T, Wang J, Wang C. Review of oxygen-enhanced lung mri: Pulse sequences for image acquisition and T 1 measurement. Med Phys 2023; 50:5987-6007. [PMID: 37345214 DOI: 10.1002/mp.16553] [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: 08/17/2021] [Revised: 03/23/2023] [Accepted: 05/16/2023] [Indexed: 06/23/2023] Open
Abstract
Oxygen-enhanced MR imaging (OE-MRI) is a special proton imaging technique that can be performed without modifying the scanner hardware. Many fundamental studies have been conducted following the initial reporting of this technique in 1996, illustrating the high potential for its clinical application. This review aims to summarise and analyse current pulse sequences and T1 measurement methods for OE-MRI, including fundamental theories, existing pulse sequences applied to OE-MRI acquisition and T1 mapping. Wash-in and wash-out time identify lung function and are sensitive to ventilation; thus, dynamic OE-MRI is also discussed in this review. We compare OE-MRI with the primary competitive technique, hyperpolarised gas MRI. Finally, an overview of lower-field applications of OE-MRI is highlighted, as relatively recent publications demonstrated positive results. Lower-field OE-MRI, which is lower than 1.5 T, could be an alternative modality for detecting lung diseases. This educational review is aimed at researchers who want a quick summary of the steps needed to perform pulmonary OE-MRI with a particular focus on sequence design, settings, and quantification methods.
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Affiliation(s)
- Pengfei Xu
- Department of Electrical and Electronic Engineering, Faculty of Science and Engineering, University of Nottingham Ningbo China, Ningbo, China
| | - Thomas Meersmann
- Sir Peter Mansfield Magnetic Imaging Centre, University of Nottingham, Nottingham, UK
- Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute, Ningbo, China
| | - Jing Wang
- Department of Electrical and Electronic Engineering, Faculty of Science and Engineering, University of Nottingham Ningbo China, Ningbo, China
- Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute, Ningbo, China
| | - Chengbo Wang
- Department of Electrical and Electronic Engineering, Faculty of Science and Engineering, University of Nottingham Ningbo China, Ningbo, China
- Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute, Ningbo, China
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McConnell B, Stoll VM, Panayiotou H, Piechnik SK, Neubauer S, van der Geest RJ, Myerson SG, Orchard E, Bissell MM. Acute vasodilator response testing in the adult Fontan circulation using non-invasive 4D Flow MRI: a proof-of-principle study. Cardiol Young 2023; 33:1342-1349. [PMID: 35942899 DOI: 10.1017/s1047951122002426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Pulmonary vasodilator therapy in Fontan patients can improve exercise tolerance. We aimed to assess the potential for non-invasive testing of acute vasodilator response using four-dimensional (D) flow MRI during oxygen inhalation. MATERIALS AND METHODS Six patients with well-functioning Fontan circulations were prospectively recruited and underwent cardiac MRI. Ventricular anatomical imaging and 4D Flow MRI were acquired at baseline and during inhalation of oxygen. Data were compared with six age-matched healthy volunteers with 4D Flow MRI scans acquired at baseline. RESULTS All six patients tolerated the MRI scan well. The dominant ventricle had a left ventricular morphology in all cases. On 4D Flow MRI assessment, two patients (Patients 2 and 6) showed improved cardiac filling with improved preload during oxygen administration, increased mitral inflow, increased maximum E-wave kinetic energy, and decreased systolic peak kinetic energy. Patient 1 showed improved preload only. Patient 5 showed no change, and patient 3 had equivocal results. Patient 4, however, showed a decrease in preload and cardiac filling/function with oxygen. DISCUSSION Using oxygen as a pulmonary vasodilator to assess increased pulmonary venous return as a marker for positive acute vasodilator response would provide pre-treatment assessment in a more physiological state - the awake patient. This proof-of-concept study showed that it is well tolerated and has shown changes in some stable patients with a Fontan circulation.
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Affiliation(s)
- Benjamin McConnell
- Department of Biomedical Imaging Science, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, UK
| | - Victoria M Stoll
- Institute of Cardiovascular Sciences, University of Birmingham, UK
- Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, UK
| | - Hannah Panayiotou
- Department of Biomedical Imaging Science, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, UK
| | - Stefan K Piechnik
- Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, UK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, UK
| | - Rob J van der Geest
- Division of Image Processing, Leiden University Medical Centrum, the Netherlands
| | - Saul G Myerson
- Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, UK
| | - Elizabeth Orchard
- Department of Congenital Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Malenka M Bissell
- Department of Biomedical Imaging Science, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, UK
- Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, UK
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Edwards L, Waterton JC, Naish J, Short C, Semple T, Jm Parker G, Tibiletti M. Imaging human lung perfusion with contrast media: A meta-analysis. Eur J Radiol 2023; 164:110850. [PMID: 37178490 DOI: 10.1016/j.ejrad.2023.110850] [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: 11/09/2022] [Revised: 04/20/2023] [Accepted: 04/22/2023] [Indexed: 05/15/2023]
Abstract
PURPOSE To pool and summarise published data of pulmonary blood flow (PBF), pulmonary blood volume (PBV) and mean transit time (MTT) of the human lung, obtained with perfusion MRI or CT to provide reliable reference values of healthy lung tissue. In addition, the available data regarding diseased lung was investigated. METHODS PubMed was systematically searched to identify studies that quantified PBF/PBV/MTT in the human lung by injection of contrast agent, imaged by MRI or CT. Only data analysed by 'indicator dilution theory' were considered numerically. Weighted mean (wM), weighted standard deviation (wSD) and weighted coefficient of variance (wCoV) were obtained for healthy volunteers (HV), weighted according to the size of the datasets. Signal to concentration conversion method, breath holding method and presence of 'pre-bolus' were noted. RESULTS PBV was obtained from 313 measurements from 14 publications (wM: 13.97 ml/100 ml, wSD: 4.21 ml/100 ml, wCoV 0.30). MTT was obtained from 188 measurements from 10 publications (wM: 5.91 s, wSD: 1.84 s wCoV 0.31). PBF was obtained from 349 measurements from 14 publications (wM: 246.26 ml/100 ml ml/min, wSD: 93.13 ml/100 ml ml/min, wCoV 0.38). PBV and PBF were higher when the signal was normalised than when it was not. No significant differences were found for PBV and PBF between breathing states or between pre-bolus and no pre-bolus. Data for diseased lung were insufficient for meta-analysis. CONCLUSION Reference values for PBF, MTT and PBV were obtained in HV. The literature data are insufficient to draw strong conclusions regarding disease reference values.
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Affiliation(s)
- Lucy Edwards
- Bioxydyn Limited, St James Tower, 7 Charlotte Street, Manchester, M1 4DZ, UK
| | - John C Waterton
- Bioxydyn Limited, St James Tower, 7 Charlotte Street, Manchester, M1 4DZ, UK; Centre for Imaging Sciences, University of Manchester, Manchester, UK
| | - Josephine Naish
- Bioxydyn Limited, St James Tower, 7 Charlotte Street, Manchester, M1 4DZ, UK; MCMR, Manchester University NHS Foundation Trust, Wythenshawe, Manchester, UK
| | - Christopher Short
- ECFS CTN - LCI Core Facility, Imperial College London, London, UK; Departments of Imaging, Royal Brompton Hospital, Sydney Street, London SW3 6NP, London, UK
| | - Thomas Semple
- Department of Radiology, The Royal Brompton Hospital, London, UK; National Heart and Lung Institute, Imperial College London, London, UK; Centre for Paediatrics and Child Health, Imperial College London, London, UK
| | - Geoff Jm Parker
- Bioxydyn Limited, St James Tower, 7 Charlotte Street, Manchester, M1 4DZ, UK; Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, UK.
| | - Marta Tibiletti
- Bioxydyn Limited, St James Tower, 7 Charlotte Street, Manchester, M1 4DZ, UK
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Saengsin K, Sittiwangkul R, Borisuthipandit T, Trongtrakul K, Tanasombatkul K, Phanacharoensawad T, Moonsawat G, Phinyo P. Predictive factors of extubation failure in pediatric cardiac intensive care unit: A single-center retrospective study from Thailand. Front Pediatr 2023; 11:1156263. [PMID: 37138565 PMCID: PMC10149922 DOI: 10.3389/fped.2023.1156263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/28/2023] [Indexed: 05/05/2023] Open
Abstract
Introduction/objective Extubation failure increases morbidity and mortality in pediatric cardiac patients, a unique population including those with congenital heart disease or acquired heart disease. This study aimed to evaluate the predictive factors of extubation failure in pediatric cardiac patients and to determine the association between extubation failure and clinical outcomes. Methods We conducted a retrospective study in the pediatric cardiac intensive care unit (PCICU) of the Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand, from July 2016 to June 2021. Extubation failure was defined as the re-insertion of the endotracheal tube within 48 hours after extubation. Multivariable log-binomial regression with generalized estimating equations (GEE) was performed to explore the predictive factors associated with extubation failure. Results We collected 318 extubation events from 246 patients. Of these, 35 (11%) events were extubation failures. In physiologic cyanosis, the extubation failure group had significantly higher SpO2 than the extubation success group (P < 0.001). The predictive factors associated with extubation failure included a history of pneumonia before extubation (RR 3.09, 95% CI 1.54-6.23, P = 0.002), stridor after extubation (RR 2.57, 95% CI 1.44-4.56, P = 0.001), history of re-intubation (RR 2.24, 95% CI 1.21-4.12, P = 0.009), and palliative surgery (RR 1.87, 95% CI 1.02-3.43, P = 0.043). Conclusion Extubation failure was identified in 11% of extubation attempts in pediatric cardiac patients. The extubation failure was associated with a longer duration of PCICU stay but not with mortality. Patients with a history of pneumonia before extubation, history of re-intubation, post-operative palliative surgery, and post-extubation stridor should receive careful consideration before extubation and close monitoring afterward. Additionally, patients with physiologic cyanosis may require balanced circulation via regulated SpO2.
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Affiliation(s)
- Kwannapas Saengsin
- Division of Cardiology, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Rekwan Sittiwangkul
- Division of Cardiology, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Thirasak Borisuthipandit
- Division of Pulmonology and Critical Care, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Konlawij Trongtrakul
- Division of Pulmonary, Critical Care Medicine, and Allergy Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Krittai Tanasombatkul
- Center for Clinical Epidemiology and Clinical Statistics, Department of Family Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | | | - Phichayut Phinyo
- Center for Clinical Epidemiology and Clinical Statistics, Department of Family Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Correspondence: Phichayut Phinyo
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Burtscher J, Mallet RT, Pialoux V, Millet GP, Burtscher M. Adaptive Responses to Hypoxia and/or Hyperoxia in Humans. Antioxid Redox Signal 2022; 37:887-912. [PMID: 35102747 DOI: 10.1089/ars.2021.0280] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Significance: Oxygen is indispensable for aerobic life, but its utilization exposes cells and tissues to oxidative stress; thus, tight regulation of cellular, tissue, and systemic oxygen concentrations is crucial. Here, we review the current understanding of how the human organism (mal-)adapts to low (hypoxia) and high (hyperoxia) oxygen levels and how these adaptations may be harnessed as therapeutic or performance enhancing strategies at the systemic level. Recent Advances: Hyperbaric oxygen therapy is already a cornerstone of modern medicine, and the application of mild hypoxia, that is, hypoxia conditioning (HC), to strengthen the resilience of organs or the whole body to severe hypoxic insults is an important preparation for high-altitude sojourns or to protect the cardiovascular system from hypoxic/ischemic damage. Many other applications of adaptations to hypo- and/or hyperoxia are only just emerging. HC-sometimes in combination with hyperoxic interventions-is gaining traction for the treatment of chronic diseases, including numerous neurological disorders, and for performance enhancement. Critical Issues: The dose- and intensity-dependent effects of varying oxygen concentrations render hypoxia- and/or hyperoxia-based interventions potentially highly beneficial, yet hazardous, although the risks versus benefits are as yet ill-defined. Future Directions: The field of low and high oxygen conditioning is expanding rapidly, and novel applications are increasingly recognized, for example, the modulation of aging processes, mood disorders, or metabolic diseases. To advance hypoxia/hyperoxia conditioning to clinical applications, more research on the effects of the intensity, duration, and frequency of altered oxygen concentrations, as well as on individual vulnerabilities to such interventions, is paramount. Antioxid. Redox Signal. 37, 887-912.
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Affiliation(s)
- Johannes Burtscher
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland.,Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Robert T Mallet
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Vincent Pialoux
- Inter-University Laboratory of Human Movement Biology EA7424, University Claude Bernard Lyon 1, University of Lyon, Lyon, France
| | - Grégoire P Millet
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland.,Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
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8
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Pusterla O, Heule R, Santini F, Weikert T, Willers C, Andermatt S, Sandkühler R, Nyilas S, Latzin P, Bieri O, Bauman G. MRI lung lobe segmentation in pediatric cystic fibrosis patients using a recurrent neural network trained with publicly accessible CT datasets. Magn Reson Med 2022; 88:391-405. [PMID: 35348244 PMCID: PMC9314108 DOI: 10.1002/mrm.29184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 11/30/2022]
Abstract
Purpose To introduce a widely applicable workflow for pulmonary lobe segmentation of MR images using a recurrent neural network (RNN) trained with chest CT datasets. The feasibility is demonstrated for 2D coronal ultrafast balanced SSFP (ufSSFP) MRI. Methods Lung lobes of 250 publicly accessible CT datasets of adults were segmented with an open‐source CT‐specific algorithm. To match 2D ufSSFP MRI data of pediatric patients, both CT data and segmentations were translated into pseudo‐MR images that were masked to suppress anatomy outside the lung. Network‐1 was trained with pseudo‐MR images and lobe segmentations and then applied to 1000 masked ufSSFP images to predict lobe segmentations. These outputs were directly used as targets to train Network‐2 and Network‐3 with non‐masked ufSSFP data as inputs, as well as an additional whole‐lung mask as input for Network‐2. Network predictions were compared to reference manual lobe segmentations of ufSSFP data in 20 pediatric cystic fibrosis patients. Manual lobe segmentations were performed by splitting available whole‐lung segmentations into lobes. Results Network‐1 was able to segment the lobes of ufSSFP images, and Network‐2 and Network‐3 further increased segmentation accuracy and robustness. The average all‐lobe Dice similarity coefficients were 95.0 ± 2.8 (mean ± pooled SD [%]) and 96.4 ± 2.5, 93.0 ± 2.0; and the average median Hausdorff distances were 6.1 ± 0.9 (mean ± SD [mm]), 5.3 ± 1.1, 7.1 ± 1.3 for Network‐1, Network‐2, and Network‐3, respectively. Conclusion Recurrent neural network lung lobe segmentation of 2D ufSSFP imaging is feasible, in good agreement with manual segmentations. The proposed workflow might provide access to automated lobe segmentations for various lung MRI examinations and quantitative analyses.
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Affiliation(s)
- Orso Pusterla
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland.,Division of Pediatric Respiratory Medicine and Allergology, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland.,Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Rahel Heule
- High Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.,Department of Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany
| | - Francesco Santini
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland.,Department of Biomedical Engineering, University of Basel, Basel, Switzerland.,Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Thomas Weikert
- Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Corin Willers
- Division of Pediatric Respiratory Medicine and Allergology, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Simon Andermatt
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Robin Sandkühler
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Sylvia Nyilas
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Philipp Latzin
- Division of Pediatric Respiratory Medicine and Allergology, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Oliver Bieri
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland.,Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Grzegorz Bauman
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, University of Basel, Basel, Switzerland.,Department of Biomedical Engineering, University of Basel, Basel, Switzerland
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Bhattacharya I, Ramasawmy R, Javed A, Lowery M, Henry J, Mancini C, Machado T, Jones A, Julien-Williams P, Lederman RJ, Balaban RS, Chen MY, Moss J, Campbell-Washburn AE. Assessment of Lung Structure and Regional Function Using 0.55 T MRI in Patients With Lymphangioleiomyomatosis. Invest Radiol 2022; 57:178-186. [PMID: 34652290 PMCID: PMC9926400 DOI: 10.1097/rli.0000000000000832] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Contemporary lower-field magnetic resonance imaging (MRI) may offer advantages for lung imaging by virtue of the improved field homogeneity. The aim of this study was to evaluate the utility of lower-field MRI for combined morphologic imaging and regional lung function assessment. We evaluate low-field MRI in patients with lymphangioleiomyomatosis (LAM), a rare lung disease associated with parenchymal cysts and respiratory failure. MATERIALS AND METHODS We performed lung imaging on a prototype low-field (0.55 T) MRI system in 65 patients with LAM. T2-weighted imaging was used for assessment of lung morphology and to derive cyst scores, the percent of lung parenchyma occupied by cysts. Regional lung function was assessed using oxygen-enhanced MRI with breath-held ultrashort echo time imaging and inhaled 100% oxygen as a T1-shortening MR contrast agent. Measurements of percent signal enhancement from oxygen inhalation and percentage of lung with low oxygen enhancement, indicating functional deficits, were correlated with global pulmonary function test measurements taken within 2 days. RESULTS We were able to image cystic abnormalities using T2-weighted MRI in this patient population and calculate cyst score with strong correlation to computed tomography measurements (R = 0.86, P < 0.0001). Oxygen-enhancement maps demonstrated regional deficits in lung function of patients with LAM. Heterogeneity of oxygen enhancement between cysts was observed within individual patients. The percent low-enhancement regions showed modest, but significant, correlation with FEV1 (R = -0.37, P = 0.007), FEV1/FVC (R = -0.33, P = 0.02), and cyst score (R = 0.40, P = 0.02). The measured arterial blood ΔT1 between normoxia and hyperoxia, used as a surrogate for dissolved oxygen in blood, correlated with DLCO (R = -0.28, P = 0.03). CONCLUSIONS Using high-performance 0.55 T MRI, we were able to perform simultaneous imaging of pulmonary structure and regional function in patients with LAM.
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Affiliation(s)
- Ipshita Bhattacharya
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Rajiv Ramasawmy
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Ahsan Javed
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Margaret Lowery
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Jennifer Henry
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Christine Mancini
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Tania Machado
- Pulmonary Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Amanda Jones
- Pulmonary Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Patricia Julien-Williams
- Pulmonary Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Robert J Lederman
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Robert S Balaban
- Systems Biology Center, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Marcus Y Chen
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Joel Moss
- Pulmonary Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Adrienne E Campbell-Washburn
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
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Bhattacharya I, Ramasawmy R, Javed A, Chen MY, Benkert T, Majeed W, Lederman RJ, Moss J, Balaban RS, Campbell-Washburn AE. Oxygen-enhanced functional lung imaging using a contemporary 0.55 T MRI system. NMR IN BIOMEDICINE 2021; 34:e4562. [PMID: 34080253 PMCID: PMC8377594 DOI: 10.1002/nbm.4562] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 04/30/2021] [Accepted: 05/04/2021] [Indexed: 05/14/2023]
Abstract
The purpose of this study was to evaluate oxygen-enhanced pulmonary imaging at 0.55 T with 3D stack-of-spirals ultrashort-TE (UTE) acquisition. Oxygen-enhanced pulmonary MRI offers the measurement of regional lung ventilation and perfusion using inhaled oxygen as a contrast agent. Low-field MRI systems equipped with contemporary hardware can provide high-quality structural lung imaging by virtue of the prolonged T2 *. Fortuitously, the T1 relaxivity of oxygen increases at lower field strengths, which is expected to improve the sensitivity of oxygen-enhanced lung MRI. We implemented a breath-held T1 -weighted 3D stack-of-spirals UTE acquisition with a 7 ms spiral-out readout. Measurement repeatability was assessed using five repetitions of oxygen-enhanced lung imaging in healthy volunteers (n = 7). The signal intensity at both normoxia and hyperoxia was strongly dependent on lung tissue density modulated by breath-hold volume during the five repetitions. A voxel-wise correction for lung tissue density improved the repeatability of percent signal enhancement maps (coefficient of variation = 34 ± 16%). Percent signal enhancement maps were compared in 15 healthy volunteers and 10 patients with lymphangioleiomyomatosis (LAM), a rare cystic disease known to reduce pulmonary function. We measured a mean percent signal enhancement of 9.0 ± 3.5% at 0.55 T in healthy volunteers, and reduced signal enhancement in patients with LAM (5.4 ± 4.8%, p = 0.02). The heterogeneity, estimated by the percent of lung volume exhibiting low enhancement, was significantly increased in patients with LAM compared with healthy volunteers (11.1 ± 6.0% versus 30.5 ± 13.1%, p = 0.01), illustrating the capability to measure regional functional deficits.
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Affiliation(s)
- Ipshita Bhattacharya
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Rajiv Ramasawmy
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Ahsan Javed
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Marcus Y Chen
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Thomas Benkert
- Siemens Healthcare GmbH, Henkestraße 127, 91052 Erlangen, Germany
| | - Waqas Majeed
- Siemens Medical Solutions USA Inc., 40 Liberty Boulevard, Malvern PA, 1935 USA
| | - Robert J Lederman
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Joel Moss
- Pulmonary Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
| | - Robert S Balaban
- Systems Biology Center, Division of Intramural Research, National Heart, Lung, and Blood I nstitute, National Institutes of Health, Bethesda MD, USA 20892
| | - Adrienne E Campbell-Washburn
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda MD, USA 20892
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11
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Campbell-Washburn AE. 2019 American Thoracic Society BEAR Cage Winning Proposal: Lung Imaging Using High-Performance Low-Field Magnetic Resonance Imaging. Am J Respir Crit Care Med 2020; 201:1333-1336. [PMID: 32298594 PMCID: PMC7258650 DOI: 10.1164/rccm.201912-2505ed] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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12
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Seith F, Pohmann R, Schwartz M, Küstner T, Othman AE, Kolb M, Scheffler K, Nikolaou K, Schick F, Martirosian P. Imaging Pulmonary Blood Flow Using Pseudocontinuous Arterial Spin Labeling (PCASL) With Balanced Steady-State Free-Precession (bSSFP) Readout at 1.5T. J Magn Reson Imaging 2020; 52:1767-1782. [PMID: 32627293 DOI: 10.1002/jmri.27276] [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: 09/17/2019] [Revised: 06/13/2020] [Accepted: 06/15/2020] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Quantitative assessment of pulmonary blood flow and visualization of its temporal and spatial distribution without contrast media is of clinical significance. PURPOSE To assess the potential of electrocardiogram (ECG)-triggered pseudocontinuous arterial spin labeling (PCASL) imaging with balanced steady-state free-precession (bSSFP) readout to measure lung perfusion under free-breathing (FB) conditions and to study temporal and spatial characteristics of pulmonary blood flow. STUDY TYPE Prospective, observational. SUBJECTS Fourteen volunteers; three patients with pulmonary embolism. FIELD STRENGTH/SEQUENCES 1.5T, PCASL-bSSFP. ASSESSMENT The pulmonary trunk was labeled during systole. The following examinations were performed: 1) FB and timed breath-hold (TBH) examinations with a postlabeling delay (PLD) of 1000 msec, and 2) TBH examinations with multiple PLDs (100-1500 msec). Scan-rescan measurements were performed in four volunteers and one patient. Images were registered and the perfusion was evaluated in large vessels, small vessels, and parenchyma. Mean structural similarity indices (MSSIM) was computed and time-to-peak (TTP) of parenchymal perfusion in multiple PLDs was evaluated. Image quality reading was performed with three independent blinded readers. STATISTICAL TESTS Wilcoxon test to compare MSSIM, perfusion, and Likert scores. Spearman's correlation to correlate TTP and cardiac cycle duration. The repeatability coefficient (RC) and within-subject coefficient of variation (wCV) for scan-rescan measurements. Intraclass correlation coefficient (ICC) for interreader agreement. RESULTS Image registration resulted in a significant (P < 0.05) increase of MSSIM. FB perfusion values were 6% higher than TBH (3.28 ± 1.09 vs. 3.10 ± 0.99 mL/min/mL). TTP was highly correlated with individuals' cardiac cycle duration (Spearman = 0.89, P < 0.001). RC and wCV were better for TBH than FB (0.13-0.19 vs. 0.47-1.54 mL/min/mL; 6-7 vs. 19-60%). Image quality was rated very good, with ICCs 0.71-0.89. DATA CONCLUSION ECG-triggered PCASL-bSSFP imaging of the lung at 1.5T can provide very good image quality and quantitative perfusion maps even under FB. The course of labeled blood through the lung shows a strong dependence on the individuals' cardiac cycle duration. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE: 2 J. MAGN. RESON. IMAGING 2020;52:1767-1782.
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Affiliation(s)
- Ferdinand Seith
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Rolf Pohmann
- High-Field MR Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
| | - Martin Schwartz
- Section on Experimental Radiology, Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany.,Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Germany
| | - Thomas Küstner
- Section on Experimental Radiology, Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany.,Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Germany
| | - Ahmed E Othman
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Manuel Kolb
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Klaus Scheffler
- High-Field MR Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany.,Department for Biomedical Magnetic Resonance, University of Tuebingen, Tuebingen, Germany
| | - Konstantin Nikolaou
- Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Fritz Schick
- Section on Experimental Radiology, Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
| | - Petros Martirosian
- Section on Experimental Radiology, Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital of Tuebingen, Tuebingen, Germany
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13
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Leutz-Schmidt P, Eichinger M, Stahl M, Sommerburg O, Biederer J, Kauczor HU, Puderbach MU, Mall MA, Wielpütz MO. Ten years of chest MRI for patients with cystic fibrosis : Translation from the bench to clinical routine. Radiologe 2019; 59:10-20. [PMID: 31172247 DOI: 10.1007/s00117-019-0553-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Despite recent advances in our knowledge about the pathophysiology and treatment of cystic fibrosis (CF), pulmonary involvement remains the most important determinant of morbidity and mortality in patients with CF. Since lung function testing may not be sensitive enough for subclinical disease progression, and because young children may have normal spirometry results over a longer period of time, imaging today plays an increasingly important role in clinical routine and research for the monitoring of CF lung disease. In this regard, chest magnetic resonance imaging (MRI) could serve as a radiation-free modality for structural and functional lung imaging. METHODS Our research agenda encompassed the entire process of development, implementation, and validation of appropriate chest MRI protocols for use with infant and adult CF patients alike. RESULTS After establishing a general MRI protocol for state-of-the-art clinical 1.5-T scanners based on the available sequence technology, a semiquantitative scoring system was developed followed by cross-validation of the method against the established modalities of computed tomography, radiography, and lung function testing. Cross-sectional studies were then set up to determine the sensitivity of the method for the interindividual variation of the disease and for changes in disease severity after treatment. Finally, the MRI protocol was implemented at multiple sites to be validated in a multicenter setting. CONCLUSION After more than a decade, lung MRI has become a valuable tool for monitoring CF in clinical routine application and as an endpoint for clinical studies.
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Affiliation(s)
- Patricia Leutz-Schmidt
- Department of Diagnostic and Interventional Radiology, Subdivision Pulmonary Imaging, University Hospital of Heidelberg, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany. .,Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany. .,Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital of Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Germany.
| | - Monika Eichinger
- Department of Diagnostic and Interventional Radiology, Subdivision Pulmonary Imaging, University Hospital of Heidelberg, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.,Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital of Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Germany
| | - Mirjam Stahl
- Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Division of Pediatric Pulmonology & Allergy and Cystic Fibrosis Center, Department of Pediatrics, University of Heidelberg, Heidelberg, Germany.,Department of Translational Pulmonology, University Hospital Heidelberg, Im Neuenheimer Feld 156, 69120, Heidelberg, Germany
| | - Olaf Sommerburg
- Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Division of Pediatric Pulmonology & Allergy and Cystic Fibrosis Center, Department of Pediatrics, University of Heidelberg, Heidelberg, Germany.,Department of Translational Pulmonology, University Hospital Heidelberg, Im Neuenheimer Feld 156, 69120, Heidelberg, Germany
| | - Jürgen Biederer
- Department of Diagnostic and Interventional Radiology, Subdivision Pulmonary Imaging, University Hospital of Heidelberg, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.,Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital of Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Germany.,Faculty of Medicine, University of Latvia, Raina bulvaris 19, LV-1586, Riga, Latvia
| | - Hans-Ulrich Kauczor
- Department of Diagnostic and Interventional Radiology, Subdivision Pulmonary Imaging, University Hospital of Heidelberg, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.,Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital of Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Germany.,Department of Translational Pulmonology, University Hospital Heidelberg, Im Neuenheimer Feld 156, 69120, Heidelberg, Germany
| | - Michael U Puderbach
- Department of Diagnostic and Interventional Radiology, Subdivision Pulmonary Imaging, University Hospital of Heidelberg, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.,Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital of Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Germany.,Department of Diagnostic and Interventional Radiology, Hufeland Hospital, Rudolph-Weiss-Straße 1-5, 99947, Bad Langensalza, Germany
| | - Marcus A Mall
- Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Department of Translational Pulmonology, University Hospital Heidelberg, Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.,Berlin Institute of Health (BIH), Anna-Louisa-Karsch-Str. 2, 10178, Berlin, Germany
| | - Mark O Wielpütz
- Department of Diagnostic and Interventional Radiology, Subdivision Pulmonary Imaging, University Hospital of Heidelberg, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.,Translational Lung Research Center Heidelberg (TLRC), German Lung Research Center (DZL), Im Neuenheimer Feld 156, 69120, Heidelberg, Germany.,Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital of Heidelberg, Röntgenstr. 1, 69126, Heidelberg, Germany
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14
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Smit B, Smulders YM, Eringa EC, Gelissen HPMM, Girbes ARJ, de Grooth HJS, Schotman HHM, Scheffer PG, Oudemans-van Straaten HM, Spoelstra-de Man AME. Hyperoxia does not affect oxygen delivery in healthy volunteers while causing a decrease in sublingual perfusion. Microcirculation 2018; 25. [PMID: 29210137 PMCID: PMC5838560 DOI: 10.1111/micc.12433] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 11/27/2017] [Indexed: 12/17/2022]
Abstract
Objective To determine the human dose‐response relationship between a stepwise increase in arterial oxygen tension and its associated changes in DO2 and sublingual microcirculatory perfusion. Methods Fifteen healthy volunteers breathed increasing oxygen fractions for 10 minutes to reach arterial oxygen tensions of baseline (breathing air), 20, 40, 60 kPa, and max kPa (breathing oxygen). Systemic hemodynamics were measured continuously by the volume‐clamp method. At the end of each period, the sublingual microcirculation was assessed by SDF. Results Systemic DO2 was unchanged throughout the study (Pslope = .8). PVD decreased in a sigmoidal fashion (max −15% while breathing oxygen, SD18, Pslope = .001). CI decreased linearly (max −10%, SD10, Pslope < .001) due to a reduction in HR (max −10%, SD7, Pslope = .009). There were no changes in stroke volume or MAP. Most changes became apparent above an arterial oxygen tension of 20 kPa. Conclusions In healthy volunteers, supraphysiological arterial oxygen tensions have no effect on systemic DO2. Sublingual microcirculatory PVD decreased in a dose‐dependent fashion. All hemodynamic changes appear negligible up to an arterial oxygen tension of 20 kPa.
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Affiliation(s)
- Bob Smit
- Department of Intensive Care, VU University Medical Center, Amsterdam, The Netherlands
| | - Yvo M Smulders
- Department of Internal Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Etto C Eringa
- Department of Physiology, VU University Medical Center, Amsterdam, The Netherlands
| | - Harry P M M Gelissen
- Department of Intensive Care, VU University Medical Center, Amsterdam, The Netherlands
| | - Armand R J Girbes
- Department of Intensive Care, VU University Medical Center, Amsterdam, The Netherlands
| | - Harm-Jan S de Grooth
- Department of Intensive Care, VU University Medical Center, Amsterdam, The Netherlands
| | - Hans H M Schotman
- Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands
| | - Peter G Scheffer
- Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands
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15
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Ter-Karapetyan A, Triphan SMF, Jobst BJ, Anjorin AF, Ley-Zaporozhan J, Ley S, Sedlaczek O, Biederer J, Kauczor HU, Jakob PM, Wielpütz MO. Towards quantitative perfusion MRI of the lung in COPD: The problem of short-term repeatability. PLoS One 2018; 13:e0208587. [PMID: 30532179 PMCID: PMC6287948 DOI: 10.1371/journal.pone.0208587] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 11/20/2018] [Indexed: 01/12/2023] Open
Abstract
Purpose 4D perfusion magnetic resonance imaging (MRI) with intravenous injection of contrast agent allows for a radiation-free assessment of regional lung function. It is therefore a valuable method to monitor response to treatment in patients with chronic obstructive pulmonary disease (COPD). This study was designed to evaluate its potential for monitoring short-term response to hyperoxia in COPD patients. Materials and methods 19 prospectively enrolled COPD patients (median age 66y) underwent paired dynamic contrast-enhanced 4D perfusion MRI within 35min, first breathing 100% oxygen (injection 1, O2) and then room air (injection 2, RA), which was repeated on two consecutive days (day 1 and 2). Post-processing software was employed to calculate mean transit time (MTT), pulmonary blood volume (PBV) and pulmonary blood flow (PBF), based on the indicator dilution theory, for the automatically segmented whole lung and 12 regions of equal volume. Results Comparing O2 with RA conditions, PBF and PBV were found to be significantly lower at O2, consistently on both days (p<10–8). Comparing day 2 to day 1, MTT was shorter by 0.59±0.63 s (p<10–8), PBF was higher by 22±80 ml/min/100ml (p<3·10–4), and PBV tended to be lower by 0.2±7.2 ml/100ml (p = 0.159) at both, RA and O2, conditions. Conclusion The second injection (RA) yielded higher PBF and PBV, which apparently contradicts the established hypothesis that hyperoxia increases lung perfusion. Quantification of 4D perfusion MRI by current software approaches may thus be limited by residual circulating contrast agent in the short-term and even the next day.
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Affiliation(s)
- Alvard Ter-Karapetyan
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik at University of Heidelberg, Heidelberg, Germany
| | - Simon M. F. Triphan
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Research Center Magnetic Resonance Bavaria (MRB), Würzburg, Germany
- * E-mail:
| | - Bertram J. Jobst
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik at University of Heidelberg, Heidelberg, Germany
| | - Angela F. Anjorin
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik at University of Heidelberg, Heidelberg, Germany
| | - Julia Ley-Zaporozhan
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Munich, Germany
| | - Sebastian Ley
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Munich, Germany
- Diagnostic & Interventional Radiology, Chirurgisches Klinikum München Süd, Munich, Germany
| | - Oliver Sedlaczek
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik at University of Heidelberg, Heidelberg, Germany
| | - Jürgen Biederer
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Radiologie Darmstadt, Department of Radiology, County Hospital Gross-Gerau, Gross-Gerau, Germany
| | - Hans-Ulrich Kauczor
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik at University of Heidelberg, Heidelberg, Germany
| | - Peter M. Jakob
- Research Center Magnetic Resonance Bavaria (MRB), Würzburg, Germany
- Department of Experimental Physics Julius-Maximilians Universität, Würzburg, Germany
| | - Mark O. Wielpütz
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), Member of the German Lung Research Center (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik at University of Heidelberg, Heidelberg, Germany
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Arai TJ, Horn FC, Sá RC, Rao MR, Collier GJ, Theilmann RJ, Prisk GK, Wild JM. Comparison of quantitative multiple-breath specific ventilation imaging using colocalized 2D oxygen-enhanced MRI and hyperpolarized 3He MRI. J Appl Physiol (1985) 2018; 125:1526-1535. [PMID: 30161004 PMCID: PMC6295484 DOI: 10.1152/japplphysiol.00500.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Revised: 08/08/2018] [Accepted: 08/20/2018] [Indexed: 11/22/2022] Open
Abstract
Two magnetic resonance specific ventilation imaging (SVI) techniques, namely, oxygen-enhanced proton (OE-1H) and hyperpolarized 3He (HP-3He), were compared in eight healthy supine subjects [age 32 (6) yr]. An in-house radio frequency coil array for 1H configured with the 3He transmit-receive coil in situ enabled acquisition of SVI data from two nuclei from the same slice without repositioning the subjects. After 3 × 3 voxel downsampling to account for spatial registration errors between the two SV images, the voxel-by-voxel correlation coefficient of two SV maps ranged from 0.11 to 0.63 [0.46 mean (0.17 SD); P < 0.05]. Several indexes were analyzed and compared from the tidal volume-matched SV maps: the mean of SV log-normal distribution (SVmean), the standard deviation of the distribution as a measure of SV heterogeneity (SVwidth), and the gravitational gradient (SVslope). There were no significant differences in SVmean [OE-1H: 0.28 (0.08) and HP-3He: 0.32 (0.14)], SVwidths [OE-1H: 0.28 (0.08) and HP-3He: 0.27 (0.10)], and SVslopes [OE-1H: -0.016 (0.006) cm-1 and HP-3He: -0.013 (0.007) cm-1]. Despite the statistical similarities of the population averages, Bland-Altman analysis demonstrated large individual intertechnique variability. SDs of differences in these indexes were 42% (SVmean), 46% (SVwidths), and 62% (SVslopes) of their corresponding overall mean values. The present study showed that two independent, spatially coregistered, SVI techniques presented a moderate positive voxel-by-voxel correlation. Population averages of SVmean, SVwidth, and SVslope were in close agreement. However, the lack of agreement when the data sets were analyzed individually might indicate some fundamental mechanistic differences between the techniques. NEW & NOTEWORTHY To the best of our knowledge, this is the first cross-comparison of two different specific ventilation (SV) MRI techniques in the human lung (i.e., oxygen-enhanced proton and hyperpolarized 3He). The present study showed that two types of spatially coregistered SV images presented a modest positive correlation. The two techniques also yielded similar population averages of SV indexes such as log-normal mean, SV heterogeneity, and the gravitational slope, albeit with some intersubject variability.
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Affiliation(s)
- Tatsuya J Arai
- POLARIS, Academic Unit of Radiology, University of Sheffield , Sheffield , United Kingdom
- Pulmonary Imaging Laboratory, University of California, San Diego, La Jolla, California
| | - Felix C Horn
- POLARIS, Academic Unit of Radiology, University of Sheffield , Sheffield , United Kingdom
| | - Rui Carlos Sá
- Pulmonary Imaging Laboratory, University of California, San Diego, La Jolla, California
| | - Madhwesha R Rao
- POLARIS, Academic Unit of Radiology, University of Sheffield , Sheffield , United Kingdom
| | - Guilhem J Collier
- POLARIS, Academic Unit of Radiology, University of Sheffield , Sheffield , United Kingdom
| | - Rebecca J Theilmann
- Pulmonary Imaging Laboratory, University of California, San Diego, La Jolla, California
| | - G Kim Prisk
- Pulmonary Imaging Laboratory, University of California, San Diego, La Jolla, California
| | - Jim M Wild
- POLARIS, Academic Unit of Radiology, University of Sheffield , Sheffield , United Kingdom
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Smit B, Smulders YM, van der Wouden JC, Oudemans-van Straaten HM, Spoelstra-de Man AME. Hemodynamic effects of acute hyperoxia: systematic review and meta-analysis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2018; 22:45. [PMID: 29477145 PMCID: PMC6389225 DOI: 10.1186/s13054-018-1968-2] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 01/26/2018] [Indexed: 02/06/2023]
Abstract
Background In clinical practice, oxygen is generally administered to patients with the intention of increasing oxygen delivery. Supplemental oxygen may, however, cause arterial hyperoxia, which is associated with hemodynamic alterations. We performed a systematic review and meta-analysis of the literature to determine the effect of hyperoxia on central hemodynamics and oxygen delivery in healthy volunteers and cardiovascular-compromised patients. Methods PubMed and EMBASE were searched up to March 2017. Studies with adult humans investigating changes in central hemodynamics or oxygen delivery induced by acute normobaric hyperoxia were included. Studies focusing on lung, retinal, or brain parameters were not included. We extracted subject and oxygen exposure characteristics, indexed and unindexed values for heart rate, stroke volume, cardiac output, mean arterial pressure (MAP), systemic vascular resistance, and oxygen delivery during normoxia and hyperoxia. For quantitative synthesis of the data, a random-effects ratio of means (RoM) model was used. Results We identified 33 studies with 42 datasets. Study categories included healthy volunteers (n = 22 datasets), patients with coronary artery disease (CAD; n = 6), heart failure (HF; n = 6), coronary artery bypass graft (CABG; n = 3) and sepsis (n = 5). Hyperoxia (arterial oxygen tension of 234–617 mmHg) reduced cardiac output (CO) by 10–15% in both healthy volunteers (−10.2%, 95% confidence interval (CI) −12.9% to −7.3%) and CAD (−9.6%, 95% CI −12.3% to −6.9%) or HF patients (−15.2%, 95% CI −21.7% to −8.2%). No significant changes in cardiac output were seen in CABG or septic patients (−3%). Systemic vascular resistance increased remarkably in patients with heart failure (24.6%, 95% CI 19.3% to 30.1%). In healthy volunteers, and those with CAD and CABG, the effect was smaller (11–16%) and was virtually absent in patients with sepsis (4.3%, 95% CI −3.2% to 12.3%). No notable effect on MAP was found in any group (2–3%). Oxygen delivery was not altered by hyperoxia. Considerable heterogeneity existed between study results, likely due to methodological differences. Conclusions Hyperoxia may considerably decrease cardiac output and increase systemic vascular resistance, but effects differ between patient categories. Heart failure patients were the most sensitive while no hemodynamic effects were seen in septic patients. There is currently no evidence supporting the notion that oxygen supplementation increases oxygen delivery. Electronic supplementary material The online version of this article (10.1186/s13054-018-1968-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bob Smit
- Department of Intensive Care, VU University Medical Center, De Boelelaan 1117, 1007, MB, Amsterdam, the Netherlands.
| | - Yvo M Smulders
- Department of Internal Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Johannes C van der Wouden
- Department of General Practice and Elderly Care Medicine, Amsterdam Public Health research institute, VU University Medical Center, Amsterdam, the Netherlands
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Kindvall SSI, Diaz S, Svensson J, Wollmer P, Olsson LE. The change of longitudinal relaxation rate in oxygen enhanced pulmonary MRI depends on age and BMI but not diffusing capacity of carbon monoxide in healthy never-smokers. PLoS One 2017; 12:e0177670. [PMID: 28494006 PMCID: PMC5426684 DOI: 10.1371/journal.pone.0177670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 05/01/2017] [Indexed: 12/02/2022] Open
Abstract
OBJECTIVE Oxygen enhanced pulmonary MRI is a promising modality for functional lung studies and has been applied to a wide range of pulmonary conditions. The purpose of this study was to characterize the oxygen enhancement effect in the lungs of healthy, never-smokers, in light of a previously established relationship between oxygen enhancement and diffusing capacity of carbon monoxide in the lung (DL,CO) in patients with lung disease. METHODS In 30 healthy never-smoking volunteers, an inversion recovery with gradient echo read-out (Snapshot-FLASH) was used to quantify the difference in longitudinal relaxation rate, while breathing air and 100% oxygen, ΔR1, at 1.5 Tesla. Measurements were performed under multiple tidal inspiration breath-holds. RESULTS In single parameter linear models, ΔR1 exhibit a significant correlation with age (p = 0.003) and BMI (p = 0.0004), but not DL,CO (p = 0.33). Stepwise linear regression of ΔR1 yields an optimized model including an age-BMI interaction term. CONCLUSION In this healthy, never-smoking cohort, age and BMI are both predictors of the change in MRI longitudinal relaxation rate when breathing oxygen. However, DL,CO does not show a significant correlation with the oxygen enhancement. This is possibly because oxygen transfer in the lung is not diffusion limited at rest in healthy individuals. This work stresses the importance of using a physiological model to understand results from oxygen enhanced MRI.
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Affiliation(s)
| | - Sandra Diaz
- Medical Radiology, Translational Medicine, Lund University, Malmö, Sweden
| | - Jonas Svensson
- Medical Imaging and Physiology, Skane University Hospital, Lund, Sweden
| | - Per Wollmer
- Clinical Physiology, Translational Medicine, Lund University, Malmö, Sweden
| | - Lars E. Olsson
- Medical Radiation Physics, Translational Medicine, Lund University, Malmö, Sweden
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Czerner CP, Winther HB, Zapf A, Wacker F, Vogel-Claussen J. Breath-hold and free-breathing 2D phase-contrast MRI for quantification of oxygen-induced changes of pulmonary circulation dynamics in healthy volunteers. J Magn Reson Imaging 2017; 46:1698-1706. [PMID: 28383791 DOI: 10.1002/jmri.25724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/21/2017] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To evaluate the effect of inhaled 100% oxygen on pulmonary circulation dynamics in healthy volunteers using 2D phase-contrast magnetic resonance imaging (2D PC MRI). MATERIALS AND METHODS Twenty-one healthy volunteers were examined at 1.5T. Through-plane 2D PC MRI measurements were performed in the main pulmonary artery during free-breathing and breath-hold. Acceleration time and volume, maximum and minimum area, area change, average and maximum mean velocity, forward volume, heart rate, as well as blood pressure were determined. At baseline, subjects breathed room air. After application of a closed-fit full face mask, three further measurements were conducted: at room air (control), directly after starting 15 L/min 100% oxygen (wash-in), and after 5 minutes during continuous oxygen supply (saturation). Data were analyzed with a mixed linear model. Skewed distributed variables were rank-transformed. Tukey contrasts with family-wise adjusted P-values were applied for pairwise comparisons. RESULTS Inhaled oxygen affected several hemodynamic parameters. Average mean velocity (P < 0.01: breath-hold during wash-in and saturation, P = 0.03: free-breathing during saturation) and maximum mean velocity (P < 0.01: breath-hold and free-breathing during saturation) decreased. When obtained during free-breathing, acceleration volume (P = 0.02: saturation), area change (P = 0.02: saturation), and maximum area (P = 0.02: wash-in, P = 0.03: saturation) increased, while minimum area and forward volume did not change. CONCLUSION Oxygen alters pulmonary circulation dynamics in the main pulmonary artery of healthy volunteers, which can be reliably detected using 2D phase-contrast MRI. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1698-1706.
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Affiliation(s)
- Christoph P Czerner
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany
| | - Hinrich B Winther
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany
| | - Antonia Zapf
- Department of Medical Statistics, University Medical Center Göttingen, Göttingen, Germany
| | - Frank Wacker
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany
| | - Jens Vogel-Claussen
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany
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Differentiation of Impaired From Preserved Hemodynamics in Patients With Fontan Circulation Using Real-time Phase-velocity Cardiovascular Magnetic Resonance. J Thorac Imaging 2017; 32:159-168. [PMID: 28346330 PMCID: PMC5538303 DOI: 10.1097/rti.0000000000000261] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Supplemental Digital Content is available in the text. Purpose: Progressive impairment of hemodynamics in patients with Fontan circulation is common, multifactorial, and associated with decreased quality of life and increased morbidity. We sought to assess hemodynamic differences between patients with preserved (preserved Fontans) and those with impaired circulation (impaired Fontans) after pulmonary vasodilation using oxygen and under forced breathing conditions. Materials and Methods: Real-time phase-contrast cardiovascular magnetic resonance was performed using non–ECG triggered echo-planar imaging (temporal resolution=24 to 28 ms) in the ascending aorta (AAo) and superior vena cava (SVC)/inferior vena cava (IVC) on room air, after 100% oxygen inhalation (4 L/min; 10 min) and on forced breathing in 29 Fontan patients (17.2±7.3 y) and in 32 controls on room air (13.4±3.7 y). The simultaneously recorded patients’ respiratory cycle was divided into 4 segments (expiration, end-expiration, inspiration, and end-inspiration) to generate respiratory-dependent stroke volumes (SVs). The imaging data were matched with physiological data and analyzed with home-made software. Results: The mean SVi (AAo) was 46.1±11.1 mL/m2 in preserved Fontans versus 30.4±6.2 mL/m2 in impaired Fontans (P=0.002) and 51.1±6.9 mL/m2 in controls (P=0.107). The cutoff value for differentiation of Fontan groups was SVi (AAo, end-expiratory) of 32.1 mL/m2. After hyperoxygenation, the mean SVi (AAo) increased to 48.7±12.7 mL/m2 in preserved Fontans (P=0.045) but remained unchanged in impaired Fontans (31.1±5.8 mL/m2, P=0.665). Simultaneously, heart rates decreased from 75.2±15.9 to 70.8±16.4 bpm (preserved; P=0.000) but remained unchanged in impaired circulation (baseline: 84.1±9.8 bpm, P=0.612). Compared with physiological respiration, forced breathing increased the maximum respiratory-related cardiac index difference (ΔCImax) in preserved Fontans (SVC: 2.5-fold, P=0.000; and IVC: 1.8-fold, P=0.000) and to a lower extent in impaired Fontans (both veins, 1.5-fold; P(SVC)=0.011, P(IVC)=0.013). There was no impact on mean blood flow. Conclusions: Oxygen affected the pulmonary vascular system by vasodilation and increased SVi in preserved Fontans but had no effect on impaired Fontans. Forced breathing increased ΔCImax but did not change the mean blood flow by sole activation of the ventilatory pump. End-expiratory aortic SVi represents a valuable measure for classifying the severity of Fontan hemodynamics impairment.
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Tedjasaputra V, Bouwsema MM, Stickland MK. Effect of aerobic fitness on capillary blood volume and diffusing membrane capacity responses to exercise. J Physiol 2016; 594:4359-70. [PMID: 26959808 PMCID: PMC4967759 DOI: 10.1113/jp272037] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 02/22/2016] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Endurance trained athletes exhibit enhanced cardiovascular function compared to non-athletes, although it is considered that exercise training does not enhance lung structure and function. An increased pulmonary capillary blood volume at rest is associated with a higher V̇O2 max . In the present study, we compared the diffusion capacity, pulmonary capillary blood volume and diffusing membrane capacity responses to exercise in endurance-trained males compared to non-trained males. Exercise diffusion capacity was greater in athletes, secondary to an increased membrane diffusing capacity, and not pulmonary capillary blood volume. Endurance-trained athletes appear to have differences within the pulmonary membrane that facilitate the increased O2 demand needed for high-level exercise. ABSTRACT Endurance-trained athletes exhibit enhanced cardiovascular function compared to non-athletes, allthough it is generally accepted that exercise training does not enhance lung structure and function. Recent work has shown that an increased resting pulmonary capillary blood volume (VC ) is associated with a higher maximum oxygen consumption (V̇O2 max ), although there have been no studies to date examining how aerobic fitness affects the VC response to exercise. Based on previous work, we hypothesized that endurance-trained athletes will have greater VC compared to non-athletes during cycling exercise. Fifteen endurance-trained athletes (HI: V̇O2 max 64.6 ± 1.8 ml kg(-1) min(-1) ) and 14 non-endurance trained males (LO: V̇O2 max 45.0 ± 1.2 ml kg(-1) min(-1) ) were matched for age and height. Haemoglobin-corrected diffusion capacity (DLCO), VC and diffusing membrane capacity (DM ) were determined using the Roughton and Forster () multiple fraction of inspired O2 (FI O2 )-DLCO method at baseline and during incremental cycle exercise up to 90% of peak O2 consumption. During exercise, both groups exhibited increases in DLCO, DM and VC with exercise intensity. Athletes had a greater DLCO and greater DM at 80 and 90% of V̇O2 max compared to non-athletes. However, VC was not different between groups during exercise. In contrast to our hypothesis, exercise VC was not greater in endurance-trained subjects compared to controls; rather, the increased DLCO in athletes at peak exercise was secondary to an enhanced DM . These findings suggest that endurance-trained athletes appear to have differences within the pulmonary membrane that facilitate the increased O2 demand needed for high-level exercise.
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Affiliation(s)
- Vincent Tedjasaputra
- Pulmonary Division, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
- Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada
| | - Melissa M Bouwsema
- Pulmonary Division, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
- Faculty of Physical Education and Recreation, University of Alberta, Edmonton, Alberta, Canada
| | - Michael K Stickland
- Pulmonary Division, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
- GF MacDonald Centre for Lung Health, Covenant Health, Edmonton, Alberta, Canada
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Wielpütz MO, Kauczor HU. Imaging cystic fibrosis lung disease with MRI. IMAGING 2016. [DOI: 10.1183/2312508x.10002415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Habre W, Peták F. Perioperative use of oxygen: variabilities across age. Br J Anaesth 2014; 113 Suppl 2:ii26-36. [DOI: 10.1093/bja/aeu380] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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LI Y, TESSELAAR E, BORGES JB, BÖHM SH, SJÖBERG F, JANEROT-SJÖBERG B. Hyperoxia affects the regional pulmonary ventilation/perfusion ratio: an electrical impedance tomography study. Acta Anaesthesiol Scand 2014; 58:716-25. [PMID: 24762189 DOI: 10.1111/aas.12323] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND The way in which hyperoxia affects pulmonary ventilation and perfusion is not fully understood. We investigated how an increase in oxygen partial pressure in healthy young volunteers affects pulmonary ventilation and perfusion measured by thoracic electrical impedance tomography (EIT). METHODS Twelve semi-supine healthy male volunteers aged 21-36 years were studied while breathing room air and air-oxygen mixtures (FiO2) that resulted in predetermined transcutaneous oxygen partial pressures (tcPO2) of 20, 40 and 60 kPa. The magnitude of ventilation (ΔZv) and perfusion (ΔZQ)-related changes in cyclic impedance variations, were determined using an EIT prototype equipped with 32 electrodes around the thorax. Regional changes in ventral and dorsal right lung ventilation (V) and perfusion (Q) were estimated, and V/Q ratios calculated. RESULTS There were no significant changes in ΔZv with increasing tcPO2 levels. ΔZQ in the dorsal lung increased with increasing tcPO2 (P = 0.01), whereas no such change was seen in the ventral lung. There was a simultaneous decrease in V/Q ratio in the dorsal region during hyperoxia (P = 0.04). Two subjects did not reach a tcPO2 of 60 kPa despite breathing 100% oxygen. CONCLUSION These results indicate that breathing increased concentrations of oxygen induces pulmonary vasodilatation in the dorsal lung even at small increases in FiO2. Ventilation remains unchanged. Local mismatch of ventilation and perfusion occurs in young healthy men, and the change in ventilation/perfusion ratio can be determined non-invasively by EIT.
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Affiliation(s)
- Y. LI
- Department of Anesthesiology; Shaoxing People's Hospital of Zhejiang University; Shaoxing City China
- Department of Clinical and Experimental Medicine; Linköping University; Linköping Sweden
| | - E. TESSELAAR
- Department of Clinical and Experimental Medicine; Linköping University; Linköping Sweden
| | - J. B. BORGES
- Hedenstierna Laboratory; Department of Surgical Sciences; Section of Anesthesiology & Critical Care; Uppsala University; Uppsala Sweden
- Laboratório de Pneumologia LIM-09; Disciplina de Pneumologia; Heart Institute (Incor); Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo; São Paulo Brazil
| | | | - F. SJÖBERG
- Department of Clinical and Experimental Medicine; Linköping University; Linköping Sweden
- Department of Hand; Plastic Surgery and Intensive Care; Linköping University Hospital; Linköping Sweden
| | - B. JANEROT-SJÖBERG
- Department of Clinical Science; Intervention and Technology; Karolinska Institutet; Stockholm Sweden
- Department of Clinical Physiology; Karolinska University Hospital; Stockholm Sweden
- School of Technology and Health; KTH; Royal Institute of Technology; Stockholm Sweden
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Abstract
Lung involvement in cystic fibrosis (CF) disease continues to be a major life-limiting factor of this autosomal recessive genetic disorder. Efforts made toward early diagnosis and advances in therapy have led to sustained survival of affected patients, and many are now of adult age. Because imaging provides detailed information on regional distribution of CF lung disease, repetitive imaging is required for severity assessment and therapy monitoring not only in clinical routine but also for interventional trials. Computed tomography has long succeeded chest radiograph because it provides the highest morphologic detail of airway and parenchymal changes. This is inseparably accompanied by an increase in radiation exposure to CF individuals, who are critically susceptible to, and may accumulate, relevant doses during their lifetime. Magnetic resonance imaging (MRI) as an ionizing radiation-free cross-sectional imaging modality is capable of depicting anatomic hallmarks of CF lung disease at lower spatial resolution but with enhanced tissue characterization. Comprehensive functional lung imaging (imaging of respiratory mechanics, ventilation, and lung perfusion) provides valuable additional information that cannot or can hardly be obtained by any other single diagnostic procedure. The present review article strives to present the current state of lung MRI in CF, as well as its future perspectives. Functional MRI of the CF lung is at the threshold of being considered a routine application, which, supporting early diagnosis, may help to further improve the survival of CF patients.
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Lederlin M, Bauman G, Eichinger M, Dinkel J, Brault M, Biederer J, Puderbach M. Functional MRI using Fourier decomposition of lung signal: Reproducibility of ventilation- and perfusion-weighted imaging in healthy volunteers. Eur J Radiol 2013; 82:1015-22. [DOI: 10.1016/j.ejrad.2012.12.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Revised: 11/16/2012] [Accepted: 12/05/2012] [Indexed: 11/24/2022]
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Magnetic resonance imaging to assess the effect of exercise training on pulmonary perfusion and blood flow in patients with pulmonary hypertension. Eur Radiol 2012; 23:324-31. [PMID: 22886553 DOI: 10.1007/s00330-012-2606-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 06/27/2012] [Accepted: 06/29/2012] [Indexed: 02/08/2023]
Abstract
OBJECTIVES To evaluate whether careful exercise training improves pulmonary perfusion and blood flow in patients with pulmonary hypertension (PH), as assessed by magnetic resonance imaging (MR). METHODS Twenty patients with pulmonary arterial hypertension or inoperable chronic thromboembolic PH on stable medication were randomly assigned to control (n = 10) or training groups (n = 10). Training group patients received in-hospital exercise training; patients of the sedentary control group received conventional rehabilitation. Medication remained unchanged during the study period. Changes of 6-min walking distance (6MWD), MR pulmonary flow (peak velocity) and MR perfusion (pulmonary blood volume) were assessed from baseline to week 3. RESULTS After 3 weeks of training, increases in mean 6MWD (P = 0.004) and mean MR flow peak velocity (P = 0.012) were significantly greater in the training group. Training group patients had significantly improved 6MWD (P = 0.008), MR flow (peak velocity -9.7 ± 8.6 cm/s, P = 0.007) and MR perfusion (pulmonary blood volume +2.2 ± 2.7 mL/100 mL, P = 0.017), whereas the control group showed no significant changes. CONCLUSION The study indicates that respiratory and physical exercise may improve pulmonary perfusion in patients with PH. Measurement of MR parameters of pulmonary perfusion might be an interesting new method to assess therapy effects in PH. The results of this initial study should be confirmed in a larger study group.
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Ley S, Ley-Zaporozhan J. Pulmonary perfusion imaging using MRI: clinical application. Insights Imaging 2011; 3:61-71. [PMID: 22695999 PMCID: PMC3292645 DOI: 10.1007/s13244-011-0140-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 11/16/2011] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Lung perfusion is one of the key components of oxygenation. It is hampered in pulmonary arterial diseases and secondary due to parenchymal diseases. METHODS Assessment is frequently required during the workup of a patient for either of these disease categories. RESULTS This review provides insight into imaging techniques, qualitative and quantitative evaluation, and focuses on clinical application of MR perfusion. CONCLUSION The two major techniques, non-contrast-enhanced (arterial spin labeling) and contrast-enhanced perfusion techniques, are discussed.
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Affiliation(s)
- Sebastian Ley
- Division of Cardiothoracic Imaging, Department of Medical Imaging, Toronto General Hospital, University of Toronto and University Health Network, Toronto General Hospital, 585 University Avenue, Toronto, Ontario, M5G 2N2, Canada,
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Maxien D, Dietrich O, Thieme SF, Förster S, Behr J, Reiser MF, Nikolaou K. Value of oxygen-enhanced MRI of the lungs in patients with pulmonary hypertension: A qualitative and quantitative approach. J Magn Reson Imaging 2011; 35:86-94. [DOI: 10.1002/jmri.22740] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 07/14/2011] [Indexed: 11/05/2022] Open
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Ley-Zaporozhan J, van Beek EJ. Imaging phenotypes of chronic obstructive pulmonary disease. J Magn Reson Imaging 2010; 32:1340-52. [DOI: 10.1002/jmri.22376] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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Dietrich O, Attenberger UI, Ingrisch M, Maxien D, Peller M, Nikolaou K, Reiser MF. Analysis of signal dynamics in oxygen-enhanced magnetic resonance imaging. Invest Radiol 2010; 45:165-73. [PMID: 20195161 DOI: 10.1097/rli.0b013e3181cd74e2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Oxygen-enhanced MRI (O2-MRI) is frequently based on a block paradigm consisting of a series of consecutive T1-weighted scans acquired during alternating blocks with inhalation of room air and of pure oxygen. This design results in a complex signal-time course for each pixel, which displays the oxygen wash-in and wash-out processes and provides spatially resolved information about the lung function. The purpose of the present study was to optimize the signal-time-course analysis to extract (pixelwise) the maximum amount of information from the acquired data, and to introduce an appropriate cross-correlation approach for data sets containing the oxygen wash-in and wash-out periods. MATERIALS AND METHODS O2-MRI data of 11 healthy volunteers were acquired with a multislice inversion-recovery single-shot turbo-spin-echo sequence at 1.5 Tesla; lung and spleen were manually segmented on all 44 acquired slices. Six different model functions were pixelwise fitted to the data and compared using the Akaike information criterion. Four different reference functions were compared for cross-correlation analysis. RESULTS The optimal model function is a piecewise exponential function (median enhancement in lung/spleen: 16.3%/14.8%) with different time constants for wash-in (29.4 seconds/72.7 seconds) and wash-out (25.1 seconds/29.6 seconds). As a new parameter, it contains the delay between switching the gas supply and the onset of the signal change (4.8 seconds/24.5 seconds). Optimal cross-correlation results were obtained with a piecewise exponential reference function, which was temporally shifted to maximize the correlation, yielding median correlation coefficients of 0.694 and 0.878, median time delays of 7.5 seconds and 38.6 seconds, and median fractions of oxygen-activated pixels of 83.6% and 92.2% in the lung and the spleen, respectively. CONCLUSIONS It was demonstrated that the pixelwise assessment of O2-MRI data are optimally performed with piecewise exponential functions. Cross-correlation analysis with a piecewise exponential reference function results in significantly higher fractions of oxygen-activated pixels than with rectangular functions.
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Affiliation(s)
- Olaf Dietrich
- Department of Clinical Radiology-Grosshadern, LMU Ludwig Maximilian University of Munich, Munich, Germany.
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Quantitative pulmonary perfusion magnetic resonance imaging: influence of temporal resolution and signal-to-noise ratio. Invest Radiol 2010; 45:7-14. [PMID: 19996761 DOI: 10.1097/rli.0b013e3181bc2d0c] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE To investigate the influence of the contrast-to-noise ratio (CNR) and temporal resolution of 3D dynamic contrast-enhanced magnetic resonance imaging on the quantification of pulmonary perfusion parameters by means of Monte-Carlo simulations and a volunteer study. METHODS Quantification of perfusion parameters such as pulmonary blood flow (PBF) and pulmonary blood volume (PBV) was simulated using synthetic data with varying CNR (noise standard deviations ranging from 0% to 25% of the parenchymal signal maximum) and different temporal resolutions from 1 to 5 seconds. Simulation results were compared with perfusion measurements in 9 healthy volunteers (age: 18-31) using dynamic 3D gradient-echo sequences with different k-space acquisition schemes, resulting in different temporal resolutions of 1.1, 1.3, and 2.0 seconds per volume and varying CNR. Lung parenchyma was segmented using a semiautomatic technique, and PBF, PBV, as well as MTT were determined pixelwise using Tikhonov-regularized deconvolution with an optimized L-curve criterion. RESULTS The simulations showed a breakdown of the deconvolution algorithm for temporal resolutions lower than 3 s. PBF was increasingly underestimated with decreasing CNR; the temporal resolution had little influence on PBF estimates in the investigated range. PBV, on the other hand, was more dependent on the temporal resolution and showed less, but noticeable influence of the CNR. For low temporal resolutions, PBV was overestimated.In the volunteer study, no significant differences of PBF between the different sequences were found; however, PBV was underestimated by the slowest sequence, in contrast to the simulation results. CONCLUSION Both the mathematical simulations and volunteer measurements showed that the temporal resolution has less influence than the CNR on the quantification of PBF. On the other hand, PBV is more influenced by temporal resolution than by CNR. This indicates that the gain in measurement speed that can be obtained by modern acceleration schemes need not be invested in ultra-high temporal resolution. Instead, sequence optimization should aim for a suitable balance of sufficient CNR on the one hand, and sufficient temporal resolution on the other hand, whereas maintaining a high spatial resolution.
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Lung water: what you see (with computed tomography) and what you get (with a bedside device). Anesthesiology 2009; 111:933-5. [PMID: 19858867 DOI: 10.1097/aln.0b013e3181bc99ed] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Abstract
Current advances in magnetic resonance, as a diagnostic modality, are discussed in the context of publications from Investigative Radiology during 2007 and 2008. The articles relating to this topic, published during the past 2 years, are reviewed by anatomic region. The discussion concludes with a consideration of magnetic resonance contrast media, focusing on studies published in the journal, and examining in particular the potential impact of nephrogenic systemic fibrosis.
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Ley-Zaporozhan J, Puderbach M, Kauczor HU. MR for the evaluation of obstructive pulmonary disease. Magn Reson Imaging Clin N Am 2008; 16:291-308, ix. [PMID: 18474333 DOI: 10.1016/j.mric.2008.02.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Obstructive lung diseases include emphysema, chronic bronchitis, chronic obstructive pulmonary disease, asthma, and cystic fibrosis. These diseases are a heterogeneous group of pulmonary disorders that share in common obstruction of air flow and deranged gas exchange. Traditionally these diseases are evaluated with clinical testing, such as pulmonary function tests, but such tests provide only global measures of respiratory function. MR techniques designed for obstructive lung disease have the capability of directly imaging the anatomic and pathophysiologic derangements and may prove useful for monitoring response to therapy.
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Affiliation(s)
- Julia Ley-Zaporozhan
- Department of Pediatric Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg, Germany.
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Validation of Magnetic Resonance Phase-Contrast Flow Measurements in the Main Pulmonary Artery and Aorta Using Perivascular Ultrasound in a Large Animal Model. Invest Radiol 2008; 43:421-6. [DOI: 10.1097/rli.0b013e318169015d] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Magnetic Resonance Imaging of Lung Tissue: Influence of Body Positioning, Breathing and Oxygen Inhalation on Signal Decay Using Multi-Echo Gradient-Echo Sequences. Invest Radiol 2008; 43:433-8. [DOI: 10.1097/rli.0b013e3181690191] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Advances in clinical magnetic resonance (MR) are discussed in this review in the context of publications from Investigative Radiology during 2006 and 2007. The articles relevant to this topic, published during this 2 year time period, are considered as organized by anatomic region. An additional final focus of discussion is in regards to those studies involving MR contrast media.
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