Comparison of Free‐Breathing 3D Phase‐Resolved Functional Lung (PREFUL) MRI With Dynamic 19F Ventilation MRI in Patients With Obstructive Lung Disease and Healthy Volunteers

Abstract

BackgroundNon‐contrast‐enhanced 1H magnetic resonance imaging (MRI) with full lung coverage shows promise for assessment of regional lung ventilation but a comparison with direct ventilation measurement using 19F MRI is lacking.PurposeTo compare ventilation parameters calculated using 3D phase‐resolved functional lung (PREFUL) MRI with 19F MRI.Study TypeProspective.PopulationFifteen patients with asthma, 14 patients with chronic obstructive lung disease, and 13 healthy volunteers.Field Strength/SequenceA 3D gradient‐echo pulse sequence with golden‐angle increment and stack‐of‐stars encoding at 1.5 T.AssessmentAll participants underwent 3D PREFUL MRI and 19F MRI. For 3D PREFUL, static regional ventilation (RVent) and dynamic flow‐volume cross‐correlation metric (FVL‐CM) were calculated. For both parameters, ventilation defect percentage (VDP) values and ventilation defect (VD) maps (including a combination of both parameters [VDPCombined]) were determined. For 19F MRI, images from eight consecutive breaths under volume‐controlled inhalation of perfluoropropane were acquired. Time‐to‐fill (TTF) and wash‐in (WI) parameters were extracted. For all 19F parameters, a VD map was generated and the corresponding VDP values were calculated.Statistical TestsFor all parameters, the relationship between the two techniques was assessed using a Spearman correlation (r). Differences between VDP values were compared using Bland–Altman analysis. For regional comparison of VD maps, spatial overlap and Sørensen–Dice coefficients were computed.Results3D PREFUL VDP values were significantly correlated to VDP measures by 19F (r range: 0.59–0.70). For VDPRVent, no significant bias was observed with VDP of the third and fourth breath (bias range = −6.8:7.7%, P range = 0.25:0.30). For VDPFVL‐CM, no significant bias was found with VDP values of fourth–eighth breaths (bias range = −2.0:12.5%, P range = 0.12:0.75). The overall spatial overlap of all VD maps increased with each breath, ranging from 61% to 81%, stabilizing at the fourth breath.Data Conclusion3D PREFUL MRI parameters showed moderate to strong correlation with 19F MRI. Depending on the 3D PREFUL VD map, the best regional agreement was found to 19F VD maps of third–fifth breath.Level of Evidence3Technical EfficacyStage 2