RT Journal Article
SR Electronic
T1 Effect of Lung Inflation State on Ventilation Defect Percent Measured using Hyperpolarized 129Xe MRI>
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 2088
DO 10.1183/13993003.congress-2020.2088
VO 56
IS suppl 64
A1 Wallace Wee
A1 Brandon Zanette
A1 Marcus Couch
A1 Elaine Stirrat
A1 Yonni Friedlander
A1 Daniel Li
A1 Samal Munidasa
A1 Sharon Dell
A1 Felix Ratjen
A1 Giles Santyr
YR 2020
UL http://erj.ersjournals.com/content/56/suppl_64/2088.abstract
AB Background: Hyperpolarized 129Xe magnetic resonance imaging(HP-MRI) is a novel technique shown to be useful in evaluating obstructive lung diseases(OLD). HP-MRI requires inhalation of a non-radioactive gas for calculating ventilatory defect percentage(VDP). In healthy adults, VDP is inversely related to lung inflation state(LIS) at time of imaging but this has not been studied in children or participants with OLD.Aim: To investigate how LIS affects VDP in participants with airway obstruction(AO).Methods: HP-MRI was conducted in a 31-year-old with moderate obstruction (FEV1pred of 65%, FEV1/FVC of 66%). Imaging was performed on a 3T MR system (Siemens Healthcare, Erlangen, Germany) and HP-MRI scans using a flexible vest coil (Clinical MR Solutions, WI, U.S.A.). Images were acquired over a 10-16 second breath-hold at 4 inflation states: residual volume(RV)+1/6 of total lung capacity(TLC), RV+1L, functional residual capacity(FRC)+1/6 of TLC, FRC+1L.Results: Figure 1A shows representative HP-MRI images with ventilation defects. Figure 1B shows VDP is greatest at RV+1/6 of TLC and inversely related with lung volume.Conclusions: This is the first of an ongoing study to assess the effect of LIS on VDP in patients with AO. In this participant, the VDP is largest at low LIS (RV+1/6 of TLC) likely due to air trapping. This underlines the importance of LIS standardization in HP-MRI to ensure accuracy of VDP measurements.FootnotesCite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 2088.This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).