Inter‐ and intravisit repeatability of free‐breathing MRI in pediatric cystic fibrosis lung disease

Abstract

Purpose The purpose of this study is to assess the intra‐ and interscan repeatability of free‐breathing phase‐resolved functional lung (PREFUL) MRI in stable pediatric cystic fibrosis (CF) lung disease in comparison to static breath‐hold hyperpolarized 129‐xenon MRI (Xe‐MRI) and pulmonary function tests. Methods Free‐breathing 1‐hydrogen MRI and Xe‐MRI were acquired from 15 stable pediatric CF patients and seven healthy age‐matched participants on two visits, 1 month apart. Same‐visit MRI scans were also performed on a subgroup of the CF patients. Following the PREFUL algorithm, regional ventilation (RVent) and regional flow volume loop cross‐correlation maps were determined from the free‐breathing data. Ventilation defect percentage (VDP) was determined from RVent maps (VDPRVent), regional flow volume loop cross‐correlation maps (VDPCC), VDPRVent ∪ VDPCC, and multi‐slice Xe‐MRI. Repeatability was evaluated using Bland–Altman analysis, coefficient of repeatability (CR), and intraclass correlation. Results Minimal bias and no significant differences were reported for all PREFUL MRI and Xe‐MRI VDP parameters between intra‐ and intervisits (all P > 0.05). Repeatability of VDPRVent, VDPCC, VDPRVent ∪ VDPCC, and multi‐slice Xe‐MRI were lower between the two‐visit scans (CR = 14.81%, 15.36%, 16.19%, and 9.32%, respectively) in comparison to the same‐day scans (CR = 3.38%, 2.90%, 1.90%, and 3.92%, respectively). pulmonary function tests showed high interscan repeatability relative to PREFUL MRI and Xe‐MRI. Conclusion PREFUL MRI, similar to Xe‐MRI, showed high intravisit repeatability but moderate intervisit repeatability in CF, which may be due to inherent disease instability, even in stable patients. Thus, PREFUL MRI may be considered a suitable outcome measure for future treatment response studies.

Effect of CFTR modulator therapy with elexacaftor/tezacaftor/ivacaftor on pulmonary ventilation derived by 3D phase-resolved functional lung MRI in cystic fibrosis patients

“…Secondly, the repeatability of 3D PREFUL–derived dynamic parameters in CF patients has not been examined yet. Recent repeatability results in chronic obstructive pulmonary disease patients and stable CF patients showed no significant bias between repeated measurements of 3D and 2D PREFUL, respectively [ 14 , 28 ]. This supports our results that the differences in 3D PREFUL parameters between baseline and post-treatment acquisition are a true response to ETI therapy.…”

Contrast agent-free functional magnetic resonance imaging with matrix pencil decomposition to quantify abnormalities in lung perfusion and ventilation in patients with cystic fibrosis

“…Fourier decomposition MRI (FD-MRI) ( 30 ) was the basis for several derivatives. Matrix pencil decomposition MRI (MP-MRI) ( 31 , 32 ) and phase resolved functional lung MRI (PREFUL-MRI) ( 29 ) have been shown to simultaneously assess lung ventilation and perfusion in CF patients ( 16 , 33 , 34 ). Previously, simultaneous assessment of lung ventilation and perfusion was only possible with nuclear medicine techniques with the use of radioisotopes, whereas inhalation of hyperpolarized gases only allows studies of ventilation ( 12 , 35–37 ).…”