Work

Comparison of Hyperpolarized 3He and 129Xe MR Imaging in Cystic Fibrosis Patients

Year: 2021

Type: article

Abstract: Purpose In this study, we compared hyperpolarized 3 He and 129 Xe images from patients with cystic fibrosis using two commonly applied magnetic resonance sequences, standard gradient echo (GRE) and balanced steady-state free precession (TrueFISP) to quantify regional similarities and differences in signal distribution and defect analysis. Materials and Methods Ten patients (7M/3F) with cystic fibrosis underwent hyperpolarized gas MR imaging with both 3 He and 129 Xe. Six had MRI with both GRE, and TrueFISP sequences and four patients had only GRE sequence but not TrueFISP. Ventilation defect percentages (VDPs) were calculated as lung voxels with <60% of the whole-lung hyperpolarized gas signal mean and was measured in all datasets. The voxel signal distributions of both 129 Xe and 3 He gases were visualized and compared using violin plots. VDPs of hyperpolarized 3 He and 129 Xe were compared in Bland-Altman plots; Pearson correlation coefficients were used to evaluate the relationships between inter-gas and inter-scan to assess the reproducibility. Results A significant correlation was demonstrated between 129 Xe VDP and 3 He VDP for both GRE and TrueFISP sequences ( ρ = 0.78, p <0.0004). The correlation between the GRE and TrueFISP VDP for 3 He was ρ = 0.98 and was ρ = 0.91 for 129 Xe. Overall, 129 Xe (27.2±9.4) VDP was higher than 3 He (24.3±6.9) VDP on average on cystic fibrosis patients. Conclusion In patients with cystic fibrosis, the selection of hyperpolarized 129 Xe or 3 He gas is most likely inconsequential when it comes to measure the overall lung function by VDP although 129 Xe may be more sensitive to starker lung defects, particularly when using a TrueFISP sequence.

Source: Academic Radiology

DOI: 10.1016/j.acra.2021.01.007