Lighting-Up the Lungs: An UTE MRI Investigation of the Parenchyma Signal Enhancement Due to Intra-Tracheal Administration of an Innovative Si-Based Gd Contrast Agent

Andrea Bianchi¹, Franois Lux², Gael Dournes¹, Olivier Tillement², Yannick Crmillieux¹

In this study we present the MRI investigation of the T1-enhancement of the lung signal due to the intra-tracheal administration of different concentrations of a silica-based gadolinium contrast agent, characterized by ultra-small nanoparticles and high relaxivity. The MRI investigation of the temporal evolution of the signal enhancement is also presented to get an estimate of the contrast agent residence time in the lungs. Notably high signal enhancements (> 200% for a 50 mM solution) with relatively small instilled volumes (50 l) have been measured thanks to the high S/N and the negligibility of motion artifacts, typical of the UTE sequence.