Novel translational pulmonary MRI in pediatrics: A Review of the last 10 years

Pediatric respirology presents distinctive challenges relative to adult care: patients have difficulties performing pulmonary function tests, more frequently have trouble complying, have distinct pathophysiology relative to adults, and have diseases that occur alongside normal or abnormal lung development. Understanding and disentangling the effects of disease and growth are important to identifying the pathophysiology that drives pediatric disease and affects the quality-of-life of this vulnerable group. Magnetic resonance imaging (MRI) can provide detailed images of lung structure and function using either standard 1H MRI or hyperpolarised 129Xe (xenon) gas MRI. Radiation exposure in this vulnerable group is problematic, but MRI is ionising radiation free and safe to perform in children and neonates. Exam acquisition speed has improved with some scans taking as little as four seconds. Structural imaging using proton MRI can assess the airways and locate consolidation, mucus plugging, and bronchiectasis. Dynamic structural imaging can extract information about lung motion, airway collapse, and even be used to extract ventilation and perfusion information. In the last decade, pulmonary MRI has been examined a wide variety of diseases including asthma, bronchopulmonary dysplasia, bronchiolitis obliterans, childhood interstitial lung diseases, cystic fibrosis, and multiple rare lung diseases. This multi-technique approach using MRI provides a holistic view that elucidates underlying disease mechanisms and connects them to patient outcomes and treatment response. This review will examine developments in pulmonary MRI over the past decade, with the aim of illustrating recent advances in research and how these discoveries are beginning to be applied to clinical settings.