RT Journal Article
SR Electronic
T1 Comparison of CT-based lobar ventilation models with <sup>3</sup>He MRI ventilation measurements in asthmatics
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P544
VO 44
IS Suppl 58
A1 Bilal Tahir
A1 Cedric Van Holsbeke
A1 Ireland Rob
A1 Swift Andy
A1 Felix Horn
A1 Helen Marshall
A1 Juan Parra-Robles
A1 Ruth Hartley
A1 Richard Kay
A1 Brightling Chris
A1 Jan De Backer
A1 Wim Vos
A1 Jim Wild
YR 2014
UL http://erj.ersjournals.com/content/44/Suppl_58/P544.abstract
AB Introduction CT models of ventilation can be computed from expiratory and inspiratory scans by means of the relative lobar expansion. This model has been validated against SPECT [1].Objective To compare models of lobar ventilation from CT with 3He MRI using multi-modal image registration in a population of asthma patients.Methods 29 patients with moderate-to-severe asthma underwent breath-hold CT at TLC and FRC. CT was used to segment the lobes at FRC and TLC by identification of major fissures and these were used to calculate percentage lobar ventilation [1]. 1H and 3He MRI were acquired in the same breath at FRC+1L [2], and the 1H MRI to CT registration was applied directly to 3He MRI allowing direct comparison of lobar CT ventilation with 3He.Results 3He MRI was successfully warped to inspiration CT using the transform from the 1H MRI and CT registration. The mean absolute difference between CT and 3He MRI ventilation across lobes was 4.8% (mean±SD for each lobe: RUL+RML=6.1±4.6%; RLL=5.0±5.7%; LUL=4.0±4.1%; LLL=4.6±3.7%).Conclusion This study compares percentage lobar ventilation from CT models with a direct measure of gas ventilation using 3He MRI. In so doing we validate the CT ventilation model and demonstrate that multi-modal registration allows the regional interpretation of 3He MR images on top of the underlying anatomy of the CT.References [1]Radiol 2010;257:854-62 [2]NMR Biomed 2011;24:130-34.