Impact of Reference Image Selection on Ventilation and Deformation Analysis in functional UTE Lung MRI

Motivation: Robust image registration is crucial for assessing lung deformation between respiratory states in functional lung MRI. The choice of reference image may influence the calculation of functional parameters, with impact on ventilation analysis. Goal(s): To evaluate the robustness of image registration with interchanging the reference image, and to assess the influence on ventilation analysis. Approach: Lung MR images in in- and expiration from a mixed cohort of 10 patients were co-registered twice with interchanging reference. Functional parameters (Jacobi determinant,fractional ventilation) were calculated. Agreement was evaluated with correlation and Bland-Altman analyses. Results: The algorithm demonstrates robust performance for mean Jacobian determinants and functional measures. Impact: Robust image registration is crucial for post-processing of functional lung MRI. Understanding the influence of the reference image on registration and subsequent ventilation analysis can help to establish reliable post-processing frameworks.