Abstract
PURPOSE: To quantitatively compare dynamic (19) F and single breath hyperpolarized (129) Xe MRI for the detection of ventilation abnormalities in subjects with mild cystic fibrosis (CF) lung disease. METHODS: Ten participants with stable CF and a baseline FEV1 > 70% completed a single imaging session where dynamic (19) F and single breath (129) Xe lung ventilation images were acquired on a 3T MRI scanner. Ventilation defect percentages (VDP) values between (19) F early-breath, (19) F maximum-ventilation, (129) Xe low-resolution, and (129) Xe high-resolution images were compared. Dynamic (19) F images were used to determine gas wash-in/out rates in regions of ventilation congruency and mismatch between (129) Xe and (19) F. RESULTS: VDP values from high-resolution (129) Xe images were greater than from low-resolution images (P = .001), although these values were significantly correlated (r = 0.68, P = .03). Early-breath (19) F VDP and max-vent (19) F VDP also showed significant correlation (r = 0.75, P = .012), with early-breath (19) F VDP values being significantly greater (P < .001). No correlation in VDP values were detected between either (19) F method or high-res (129) Xe images. In addition, the location and volume of ventilation defects were often different when comparing (129) Xe and (19) F images from the same subject. Areas of ventilation congruence displayed the expected ventilation kinetics, while areas of ventilation mismatch displayed abnormally slow gas wash-in and wash-out. CONCLUSION: In CF subjects, ventilation abnormalities are identified by both (19) F and HP (129) Xe imaging. However, these ventilation abnormalities are not entirely congruent. (19) F and HP (129) Xe imaging provide complementary information that enable differentiation of normally ventilated, slowly ventilated, and non-ventilated regions in the lungs.