Detection of early-stage lung disease in cystic fibrosis; comparing the sensitivity of 3He and 1H MRI, CT and LCI

Introduction Detection of early-stage lung disease in cystic fibrosis (CF) is critical to guide clinical treatment to prolong the onset of irreversible lung disease. Objective To investigate the relative sensitivity of imaging; 3 He and 1 H MRI, CT and lung clearance index (LCI) for detection of early stage lung disease in children with mild CF. Methods 11 CF patients (7-16yrs) and 5 controls (7-14yrs) were assessed with 3 He and 1 H MRI, sitting and supine multi-breath washout (MBW), low-dose CT (patients only) and pulmonary function tests. All participants had spirometry within normal range. Quantitative 3 He MRI measures were calculated. Images were read by a paediatric chest radiologist. Results The 3 He MRI measures of un-ventilated volume percentage (UVP) and ventilation heterogeneity (coefficient of variation standard deviation (CV)) were significantly higher in patients than controls (UVP 4.3 vs 2.1 and CV 10.9 vs 9.8, p Abnormalities were detected in the 3 He MRI of 10 patients, the CT of 9 patients and the 1 H MRI of 4 patients (fig 1). Sitting LCI was abnormal (>7.4) in 5 patients. All controls had normal MRI and LCI. Conclusion 3 He MRI is more sensitive to early ventilation changes in CF than LCI, 1 H MRI or pulmonary function tests. 3 He MRI and CT detected lung abnormalities in CF children with sub-clinical disease.