Comparison of CT-based Lobar Ventilation with 3He MR Imaging Ventilation Measurements

Purpose: To compare lobar lung ventilation computed from expiratory and inspiratory computed tomographic (CT) data with direct measurements of ventilation at hyperpolarized helium 3 (3He) magnetic resonance (MR) imaging by using same-breath hydrogen 1 (1H) MR imaging examinations to coregister the multimodality images. Materials and MethodsThe study was approved by the national research ethics committee, and written patient consent was obtained. Thirty patients with asthma underwent breath-hold CT at total lung capacity and functional residual capacity. 3He and 1H MR images were acquired during the same breath hold at a lung volume of functional residual capacity plus 1 L. Lobar segmentations delineated by major fissures on both CT scans were used to calculate the percentage of ventilation per lobe from the change in inspiratory and expiratory lobar volumes. CT-based ventilation was compared with 3He MR imaging ventilation by using diffeomorphic image registration of 1H MR imaging to CT, which enabled indirect registration of 3He MR imaging to CT. Statistical analysis was performed by using the Wilcoxon signed-rank test, Pearson correlation coefficient, and Bland-Altman analysis.

Comparison of CT-based Lobar Ventilation with 3He MR Imaging Ventilation Measurements Articles