Seven years of functional lung MRI in children: experiences of more than 900 matrix-pencil decomposition (MP-)MRI measurements in clinics and research

Background: Structural and functional magnetic resonance imaging (MRI) of the lung is well suited for repeated measurements especially in children, as patients are not exposed to ionizing radiation. Matrix-Pencil decomposition (MP)-MRI is a highly promising approach allowing simultaneous assessment of lung ventilation and perfusion without the need of contrast agent, hyperpolarized gas and/or specific breathing maneuvers. Aim: To report our experience of seven years lung MP-MRI measurements in children. Methods: Since 2016 we performed more than 900 functional MP-MRI lung scans in children aged 5-18 years on a standard clinical 1.5 Tesla Siemens MRI scanner. Scans were used for both, study investigations and clinical questions, and were performed together with structural lung MRI measurements. Results: MP-MRI is easily feasible even in young children and of short duration (8 minutes on average). Outcome parameters like ventilation and perfusion defect percentage (VDP, QDP) and defect distribution index (DDI) are suited as study endpoints in lung diseases, e.g. cystic fibrosis, primary ciliary dyskinesia and congenital diaphragmatic hernia. In addition, MP-MRI is of help in clinical decision making, such as assessing the residual, local ventilation and perfusion after surgery for congenital airway malformation or necrotising pneumonia. Conclusions: We have pioneered the implementation of MP-MRI into clinics and shown that MP-MRI is applicable in various study settings. It helps guiding clinical decisions and is a promising tool for follow-up of chronic lung diseases providing spatially resolved information on functional deficits.