Functional Magnetic Resonance Imaging as a new additional modality in the assessment of Primary Ciliary Dyskinesia

Abstract

Primary ciliary dyskinesia (PCD) is characterized by functional abnormalities of the cilia, leading to chronic airway infection and remodeling. Lung function tests like inert gas washout measurements detect ventilation inhomogeneity, but cannot determine its origin. Novel magnetic resonance imaging (MRI) methods such as Matrix Pencil (MP) decomposition MRI can visualize functional changes in the lung without the administration of contrast agents and the need for breathing maneuvers. This study investigates the correlation between functional and morphological MRI and lung function indices in patients with PCD. Thirty-one patients with PCD (mean age 13.5 years, range 5–28) underwent MRI and lung function tests on the same day. Functional MP-MRI provided semi-quantitative measures of the perfusion (RQ) and ventilation (RFV) impairment as percentages of the affected lung volume. Morphological MRI was evaluated using a score derived from cystic fibrosis. Lung function tests provided information about global (lung clearance index, LCI) ventilation inhomogeneity. Both MRI and inert gas washout measurements detected functional impairment in PCD: RFV ranged from 11% to 29% and RQ ranged from 9% to 28%. RFV and RQ moderately correlated with LCI (r=0.4, p=0.04; r=0.4, p=0.03, respectively). Total morphology scores strongly correlated with LCI (r=0.6, p Functional MP-MRI is a novel, sensitive and non-invasive method to detect and visualize perfusion and ventilation abnormalities. For the first time we could show a correlation between a lung function test and a functional and structural MRI in patients with PCD.