Traditional Posters: Body Imaging
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| Miranda Kirby1,2, Lindsay Mathew1,2, Andrew Wheatley1, David G. McCormack3, Grace Parraga1,4
1Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada; 2Medical Biophysics, The University of Western Ontario; 3Division of Respirology, Department of Medicine, The University of Western Ontario; 4Graduate Program in Biomedical Engineering, The University of Western Ontario Here we evaluate the associations between hyperpolarized Helium-3 Magnetic Resonance Imaging (3He MRI) longitudinal changes measured in Chronic Obstructive Pulmonary Disease (COPD) ex-smokers, with SNR and inter-observer variability. Spin density images for 15 subjects were segmented to obtain ventilation defect volume (VDV) measurements at baseline and 26 months. Inter-observer reproducibility was determined for two observers; ICC= .93, COV= 26% and r2= .78 (p<.0001). There was no significant relationship between image SNR and inter-observer variability (r=-.06, p=.75). Therefore, measurement variability is not affected by SNR and increases in VDV at follow-up may reflect COPD airway functional changes, suggestive of disease progression. 2532. Assessing the Persistence of Ventilation Defects in Asthmatics at Baseline and Following Methacholine Challenge Using Hyperpolarized 3He MRI Yanping Sun1, Linxi Shi1,2, Guoen Jin1, Sanaz Zhalehdoust Sani3, Justin L. Lui3, Stephen J. Krinzman4, John Mark Madison4, Kenneth R. Lutchen3, Mitchell S. Albert1 1Radiology, University of Massachusetts, Worcester, MA, United States; 2Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, United States; 3Biomedical Engineering, Boston University, Boston, MA, United States; 4Pulmonary, University of Massachusetts, Worcester, MA, United States We used hyperpolarized 3He MR to image subjects with asthma at two scanning sessions 45 days apart; during each session, baseline and post-methacholine scans were collected. We found that post-methacholine, defect number increased by an average of 172%. The percentage of defects that remained in the same location between imaging sessions was 75% ± 40 between baseline scans, but 96% ± 4 between post-methacholine scans. Thus, methacholine provocations in asthmatics increased defect number, but defects tended to remain in the same location from one provocation to another. Our results suggest that asthma dysfunction has an important localized component. 2533. Using Hyperpolarized 3He MRI to Evaluate Therapeutics in Cystic Fibrosis Patients Yanping Sun1, Brian O'Sullivan2, Ronn P. Walvick1,3, Austin L. Reno1, Linxi Shi1,4, Dawn Baker2, Joey Mansour1, Mitchell S. Albert1 1Radiology, University of Massachusetts, Worcester, MA, United States; 2Pediatrics, University of Massachusetts, Worcester, MA, United States; 3Biomedical Engineering, Worcester Polytechnic Institute , Worcester, MA, United States; 4Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, United States Cystic fibrosis (CF) is a genetic disease impairing chloride permeability in epithelial cells; CF causes thick, viscous mucus, leading to lung congestion, frequent infections, and over time, debilitating lung damage. In this study, we used HP 3He static ventilation MRI scans to assess improvement of lung ventilation in three CF patients following treatment with intravenous antibiotics, daily administration of hypertonic saline, and administration of rhDNase. In one of the subjects, there was a 25% increase in ventilation measured by HP 3He MRI following treatment, which corresponded with spirometry. The other two subjects showed no changes in 3He ventilation. 2534. Detection and Characterization of Physiologic Lung Changes After Placement of Bronchial Valves: A Case Study. Jaime Mata1, Talissa Altes1, Steve Springmeyer2, Jonathon Truwit1, Eduard de Lange1, Peter Sylvester1, John Mugler III1 1University of Virginia, Charlottesville, VA, United States; 2Spiration Inc, Redmond, WA, United States The purpose was to determine whether hyperpolarized helium-3 (HHe) ventilation and diffusion MR imaging can detect changes in lung function and microstructure resulting from bronchial valve placement. One subject was imaged with HHe, pre and 6-month post IBV placement. Physiological changes of the lung were observed and quantified. In conclusion, HHe MR imaging appears to provide a safe, non-invasive method for measuring functional and structural changes in the lungs after IBV placement. 2535. Acinar Structural Changes in Mild COPD Detected by in Vivo Lung Morphometry with Hyperpolarized Helium-3 MRI James D. Quirk1, Barbara A. Lutey2, Jason C. Woods1,3, Alexander L. Sukstanskii1, Mark S. Conradi, 1,3, Mario Castro2, David S. Gierada1, Dmitriy A. Yablonskiy1,3 1Radiology, Washington University School of Medicine, St. Louis, MO, United States; 2Internal Medicine, Washington University School of Medicine, St. Louis, MO, United States; 3Physics, Washington University, St. Louis, MO, United States In vivo lung morphometry with hyperpolarized helium-3 MRI is a sensitive method for detecting early emphysema and provides a unique insight into changes in the acinar microstructure. We utilized this technique to measure acinar geometrical parameters in 30 smokers and 5 healthy volunteers. Our results support the view that early emphysema progresses through dilation of alveolar ducts with retraction of alveolar walls. We also detected significant disease heterogeneity across the lung and suggest that these patterns can provide important insights into disease phenotypes and are valuable for monitoring disease progression and regression. 2536. Golden Angle Radial Imaging for Improved Visualisation of Initial Stages of Inhalation in Dynamic 3He Lung MRI Yüklə 458,11 Kb. Dostları ilə paylaş:
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