Assessment of lung disease in children with cystic fibrosis using hyperpolarized 3-Helium MRI: comparison with Shwachman score, Chrispin-Norman score and spirometry

Abstract

This study assesses the feasibility of hyperpolarized 3-Helium MRI in children with cystic fibrosis (CF) and correlates the findings with standard clinical parameters based on chest radiograph (CXR) and pulmonary function tests (PFT). An uncontrolled, observational study in eighteen children with cystic fibrosis aged 5 - 17 years (median 12.1 years), with different severity of disease was carried out. All subjects underwent routine clinical assessment including PFT and standard auxology; CXR was obtained and Shwachman and Chrispin-Norman scores calculated. Hyperpolarized 3-He magnetic resonance imaging (MRI) was carried out using a spin-exchange polarizer and a whole body 1.5 T scanner. Ventilation distribution images were obtained during a 21-second breath-hold and scored according to previously defined criteria. Spearman's non-parametric correlations test was performed to assess for statistical significance at the p<0.05 level. The children tolerated the procedure well. No desaturation events were observed during 3-He MRI. A significant, albeit moderate, correlation was found between MRI score and FEV1% predicted (r=-0.41; p=0.047) and FVC% predicted (r=-0.42; p=0.04), while there were trends of correlations between Shwachman score and MRI score (r=-0.38; p=0.06) and Shwachman score and FEV1% predicted (r=0.39; p=0.055). The feasibility of hyperpolarized 3-He MRI in children with CF was demonstrated. MRI appears to be able to demonstrate functional lung changes, although correlations with routine clinical tests are only moderate to poor. This non-ionising radiation technique could be useful for monitoring lung disease and assessing therapy in this patient population.