| 08:15 | 0057.
 | Regional ventilation measured by 3D phase-resolved functional lung MRI improves after dual bronchodilator treatment in patients with COPD Filip Klimeš1,2, Andreas Voskrebenzev1,2, Marcel Gutberlet1,2, Till Frederik Kaireit1,2, Robert Grimm3, Frank Wacker1,2, Jens Hohlfeld4,5, and Jens Vogel-Claussen1,2
1Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany, 2Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany, 3MR Application Predevelopment, Siemens Healthineers AG, Erlangen, Germany, 4Department of Clinical Airway Research, Franhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany, 5Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany Keywords: Lung, Lung, COPD, Dual bronchodilator, treatment Motivation: Bronchodilators relieve the symptoms of respiratory conditions, such as chronic obstructive lung disease (COPD). 3D PREFUL MRI offers a non-invasive assessment of pulmonary ventilation. It is unclear whether 3D PREFUL parameters are sensitive to ventilation changes induced by bronchodilators. Goal(s): To determine whether 3D PREFUL parameters enable to measure response to dual bronchodilator therapy in COPD. Approach: 3D PREFUL MRI and spirometry at baseline and 2 weeks after initiation of therapy. Results: Ventilation assessed by 3D PREFUL parameters significantly improved by bronchodilator therapy. Relative changes of 3D PREFUL ventilation defect percentage parameters were similar to relative change differences of FEV1. Impact: 3D PREFUL MRI derived ventilation maps show significantly reduced ventilation defects in COPD patients after bronchodilator therapy. This positions 3D PREFUL MRI as a promising candidate for non-invasive monitoring of regional ventilation changes in future clinical studies.
|
| 08:27 | 0058.
 | Application of Voxel-wise Lung Ventilation (VOLVE) Assessment Utilising Cross-Correlation in Chronic Obstructive Pulmonary Disease (COPD) Zachary Peggs1,2, Jonathan Brooke2, Jan Paul1,2, Christopher Bradley1,2, Andrew Cooper1,2, Charlotte E Bolton2, Ian Hall2, Susan Francis1, and Penny Gowland1
1Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom, 2NIHR Nottingham Biomedical Research Centre (BRC), Respiratory Medicine, School of Medicine, University of Nottingham, Nottingham, United Kingdom Keywords: Lung, Quantitative Imaging, COPD Motivation: To develop dynamic ventilation metrics that are robust to breathing behaviour and can identify nonlinear responses of MR signal to lung expansion. Goal(s): To extend Voxel-wise Lung Ventilation (VOLVE) analysis by incorporating cross-correlation metrics to account for phase shifts between the navigator (global) and lung parenchyma (local) respiratory signal representing delays in ventilation. Approach: Prospective pilot study using VOLVE analysis incorporating cross-correlation of navigator and lung parenchyma signals. Results: Significant differences between healthy and COPD groups in the cross-correlation metrics, with both a reduction in amplitude indicating reduced signal linearity and increase in phase shift (lag) indicating delayed ventilation. Impact: Voxel-wise Lung Ventilation (VOLVE) analysis incorporating cross-correlation and lag enables the distinction between lung regions with delayed ventilation from regions where ventilation signal is static. This additional insight into nonlinear ventilation dynamics will improve understanding of changes in lung function. |
| 08:39 | 0059.
 | Dual-center repeatability and comparison of 3D phase-resolved functional lung (PREFUL) ventilation MRI at 3T Filip Klimeš1,2, Chuan Tai Foo3,4, Marcel Gutberlet1,2, Andreas Voskrebenzev1,2, Richard McIntyre5,6, Marius Malte Wernz1,2, Robin Aaron Müller1,2, Robert Grimm7, Frank Wacker1,2, Frank Thien3,4, and Jens Vogel-Claussen1,2
1Institute of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany, 2Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover, Germany, 3Department of Respiratory Medicine, Eastern Health, Melbourne, Australia, 4Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Australia, 5Monash Biomedical Imaging, Monash University, Melbourne, Australia, 6Monash Imaging Department, Monash Health, Melbourne, Australia, 7MR Application Predevelopment, Siemens Healthineers AG, Erlangen, Germany Keywords: Lung, Lung, Repeatability Motivation: 3D phase-resolved functional lung (PREFUL) MRI provides evaluation of ventilation during free-breathing without contrast agents. The repeatability of 3D PREFUL at 3T is unknown. Goal(s): To assess the performance of 3D PREFUL in dual-center setting and to compare 3T measurement to 1.5T. Approach: Dual-center 3D PREFUL MRI in healthy volunteers Results: 3D PREFUL was feasible at 3T scanners at both centers. The repeatability assessments showed a bias only for one parameter, where it was negligibly small. Significant differences of 3D PREFUL ventilation parameters were observed between 1.5T and 3T, suggesting for pronounced susceptibility effects at 3T. Impact: Despite the pronounced differences in ventilation
parameters across the field strengths, consistently reproducible surrogates of
ventilation markers were derived from 3D PREFUL MRI using a patient-friendly
acquisition without the need for contrast agents and during free tidal
breathing. |
| 08:51 | 0060.
 | Investigating Gravitational Influence on Normal Lung Function Using PREFUL MRI on an Open Scanner Arthur Harrison1,2, Galina E Pavlovskaya1,2, Penny Gowland1,2, Thomas Meersmann1,2, Jan A Paul1,2, Rashed Sobhan1,2, Amanda Goodwin2, and Olivier Mougin1,2
1Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom, 2Nottingham NIHR Biomedical Research Centre, University of Nottingham, Nottingham, United Kingdom Keywords: Lung, Lung Motivation: Insights into the factors contributing to local ventilation and perfusion variation within the lungs are of crucial importance to improving patient care. Goal(s): To investigate the gravity dependent contributions to regional heterogeneity of normal lung function including ventilation and perfusion. Approach: With use of an open MRI system, participants were scanned in three positions to vary the direction of gravity experienced by the lungs. PREFUL analysis was employed to attain fractional ventilation, normalised perfusion, and associated Time-To-Peak markers. Results: Contributions from both gravity and physiological factors were observed in ventilation and perfusion distribution for each of the three positions. Impact: Enhanced
understanding of the causes of functional variations in healthy lungs will
allow physicians to make more informed decisions regarding patient care.
Additionally, posture dependent lung function could serve as a marker for lung
disease and support stratified treatment approaches. |
| 09:03 | 0061.
 | Simultaneous extraction of Oxygen enhanced MRI indices and α-mapping in Cystic Fibrosis Marta Tibiletti1, Christopher Short2,3, Jo Naish1,4, John Charles Waterton1,5, Mary Abkir2,3, Thomas Semple2,6, Simon Padley2,3, Jane C Davies2,3, and Geoff JM Parker1,7
1Bioxydyn Ltd, Manchester, United Kingdom, 2National Heart & Lung Institute, Imperial College London, London, United Kingdom, 3Royal Brompton Hospital, Guy's & St Thomas’ Trust, London, United Kingdom, 4MCMR, Manchester University NHS Foundation Trust, Manchester, United Kingdom, 5Centre for Imaging Sciences, University of Manchester, Manchester, United Kingdom, 6Centre for Paediatric and Child Health, Imperial College London, London, United Kingdom, 7Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom Keywords: Lung, Oxygenation Motivation: Functional lung MRI methods based on different physical principles are available, but their relationship is not well understood in disease Goal(s): Compare dynamic oxygen-enhanced MRI and ‘α-mapping’ extracted from the same acquisition with lung clearance index (LCI) in a cystic fibrosis (CF) population Approach: Oxygen enhancement at 30s to 60s after oxygen start and at plateau are compared with α-mapping in 45 CF patients. Results: α-mapping and OE-MRI correlate strongly with LCI, confirming their validity. Dynamic OE-MRI identifies areas of fast and slow enhancement, which may be areas of collateral ventilation. α-mapping cannot separate non-ventilated areas from areas of slow gas arrival. Impact: Dynamic OE-MRI and α-mapping are extracted from a single acquisition and compared in a cystic fibrosis population. Dynamic OE-MRI identifies areas of fast and slow enhancement, possible collateral ventilation. α-Index cannot separate non-ventilated areas from areas of slow gas arrival. |
| 09:15 | 0062.
 | ICA-enabled oxygen-enhanced MRI (OE-MRI) correlates with pulmonary function tests in cystic fibrosis Sarah H. Needleman1, Mina Kim1, Jamie R. McClelland1, Marta Tibiletti2, Christopher Short3,4,5, Thomas Semple3,4, Jane C. Davies3,4,5, and Geoff J. M. Parker1,2
1Centre for Medical Image Computing (CMIC), Department of Medical Physics & Biomedical Engineering, University College London, London, United Kingdom, 2Bioxydyn Limited, Manchester, United Kingdom, 3National Heart & Lung Institute, Imperial College London, London, United Kingdom, 4Royal Brompton Hospital, Guy's & St Thomas' Trust, London, United Kingdom, 5European CF Society Lung Clearance Index Core Facility, London, United Kingdom Keywords: Lung, Data Processing Motivation: There is a clinical need for non-ionising methods to assess heterogeneous lung function in cystic fibrosis (CF). Dynamic oxygen-enhanced MRI (OE-MRI) can assess regional lung function, however OE-MRI analysis is impaired by confounding signals and poor SNR. Goal(s): To evaluate the sensitivity of OE-MRI measures to the lung clearance index (LCI) in CF, with and without independent component analysis (ICA) to reduce noise. Approach: We used ICA to reduce noise in the OE-MRI measures. We evaluated the correlation between OE-MRI measures, LCI, and pulmonary function tests. Results: OE-MRI measures demonstrated significant correlation with LCI. OE-MRI measures extracted using ICA displayed clear oxygen-enhancement responses.
Impact: Dynamic lung OE-MRI measures extracted using independent component analysis (ICA) exhibited significant correlation with lung clearance index (LCI2.5) in cystic fibrosis (CF) patients, suggesting a potential application of ICA-extracted OE-MRI measures to assess regional disease severity in CF. |
| 09:27 | 0063.
 | Acceleration of Ventilation-Weighted Free-Breathing Functional 1H MRI in Pediatric Cystic Fibrosis Lung Disease Samal Munidasa1,2,3, Brandon Zanette3, Marie-Pier Dumas4, Wallace Wee4, Sharon Braganza3, Daniel Li3, Jason Woods1, Felix Ratjen4, and Giles Santyr3
1Pulmonary Medicine, Cincinnati Children's Hospital, Cincinnati, OH, United States, 2Medical Biophysics, University of Toronto, Toronto, ON, Canada, 3Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada, 4Division of Respiratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada Keywords: Lung, Lung, hyperpolarized 129-Xenon, functional lung MRI Motivation: Free-breathing pulmonary MRI acquisitions can be lengthy (i.e. 1-minute per slice) which can prove challenging for imaging pediatric lung diseases. Goal(s): The purpose of this work is to determine if reducing the free-breathing MRI scan time will produce stable ventilation defect measures that agree with hyperpolarized 129Xenon-MRI (Xe-MRI). Approach: Free-breathing MRI data acquired in cystic fibrosis patients were retrospectively truncated to compare measured Xe-MRI ventilation defects at shorter acquisition times. Results: Free-breathing MRI ventilation defects showed minimal variability and similar correlation strength to Xe-MRI following approximately 40% reductions in scan time. Impact: Free-breathing MRI can
evaluate pulmonary ventilation in pediatric cystic fibrosis lung disease in
agreement with 129Xenon-MRI but is lengthy. Accelerated
free-breathing MRI allows for decreased scan durations, without compromising
ventilation maps. This can potentially improve clinical translation, especially
in pediatrics. |
| 09:39 | 0064.
 | Preliminary Investigation of Feasibility, Tolerability, and Image Quality of Perfluoropropane Ventilation MRI in Pediatric Participants Brandon Zanette1, Faiyza S Alam1,2, Mary A Neal3,4, Peter E Thelwall3,4, Felix Ratjen1,5, and Giles Santyr1,2
1Translational Medicine, The Hospital for Sick Children, Toronto, ON, Canada, 2Medical Biophysics, University of Toronto, Toronto, ON, Canada, 3Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, United Kingdom, 4Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, United Kingdom, 5Division of Respiratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada Keywords: Lung, Lung, 19F, Fluorine-19, Ventilation, Perfluoropropane, Gas Motivation: Inert fluorinated gas MRI has potential as a lower cost alternative to hyperpolarized noble gas MRI for lung ventilation imaging. However, this technology has not yet been evaluated for use in pediatrics. Goal(s): To investigate the feasibility, tolerability, and image quality of inert fluorinated gas MRI with perfluoropropane (PFP) in pediatric participants. Approach: PFP MRI was performed in pediatric participants. Image quality, SNR, and ventilation defect percent (VDP) were evaluated. Results: PFP MRI was well-tolerated and successfully performed in all pediatric recruits. Image quality was good and permitted quantification of ventilation defect percent (VDP). Impact: PFP MRI was determined to be feasible in pediatrics, yielding ventilation images and image quality similar to hyperpolarized gas MRI. This may permit more widespread adoption for the study of pediatric lung disease in the future. |
| 09:51 | 0065.
 | Combining Hyperpolarized 129Xe MR Imaging and Spectroscopy to Estimate Pulmonary Vascular Resistance Anna Costelle1, David Mummy2, Junlan Lu1, Suphachart Leewiwatwong3, Sudarshan Rajagopal4, and Bastiaan Driehuys1,2,3
1Medical Physics, Duke University, Durham, NC, United States, 2Radiology, Duke University, Durham, NC, United States, 3Biomedical Engineering, Duke University, Durham, NC, United States, 4Cardiology, Duke University, Durham, NC, United States Keywords: Lung, Lung, Pulmonary Hypertension Motivation: Pulmonary hypertension (PH) and reduced capillary blood volume, VC’, have competing effects on oscillations of the hyperpolarized 129Xe red blood cell (RBC) resonance, rendering it difficult to distinguish PH. Goal(s): Our goal was to correct RBC oscillations for reduced VC', then use corrected oscillations to estimate pulmonary vascular resistance (PVR). Approach: We developed a model of RBC oscillations as a function of VC’ in a cohort without known PH and used this model to derive a correction factor. Corrected oscillations were regressed against known PVR in a cohort with suspected PH. Results: Corrected oscillations improved PH sensitivity and were significantly correlated to PVR. Impact: Correcting oscillations in the hyperpolarized 129Xe red blood cell resonance for reduced pulmonary capillary blood volume improves sensitivity to pulmonary hypertension and permits estimation of pulmonary vascular resistance, thereby offering a non-invasive diagnostic alternative to right heart catheterization. |
| 10:03 | 0066.
 | High resolution free-breathing respiratory-resolved volumetric lung imaging at 0.55T using stack-of-spiral out-in bSSFP Ziwei Zhao1, Bilal Tasdelen1, Nam G. Lee2, and Krishna S. Nayak1,2
1Electrical and Computer Engineering, University of Southern California, Los Angeles, CA, United States, 2Biomedical Engineering, University of Southern California, Los Angeles, CA, United States Keywords: Lung, Lung, Low-Field MRI, Data Sampling and Reconstruction, Non-Cartesian Trajectory Motivation: High resolution free-breathing structural lung imaging at 0.55T has been demonstrated using bSSFP half-radial dual-echo imaging with constrained reconstruction within ~10-min scan time. Goal(s): To develop faster high-resolution free-breathing lung imaging using spiral sampling. Approach: We employ a stack-of-spirals out-in trajectory with constrained reconstruction along with pilot-tone based respiratory navigation. Results: Structural lung imaging is demonstrated with 2mm isotropic resolution, 5-7 respiratory states, and 5-7 min scan time. 3D ventilation maps are demonstrated, showing -3.1% ~ 70.2% lung capacity during normal and deep breathing. Impact: Free-breathing SoSOi can provide simultaneous structural and functional lung imaging at 0.55T within a 5-min scan, with improved sampling efficiency and lower undersampling factor compared to bSTAR. This has implications for the evaluation of lung function and chronic lung diseases. |