Characterization of Inner Ear Inflammation in Rodents Using in Vivo Dynamic Contrast Enhanced Magnetic Resonance Imaging and Ex Vivo Light Microscopy

Johann Le Floc'h¹, Beau Pontr², Winston Tan¹, Srdjan M. Vlajkovic¹, Peter R. Thorne¹

Inner ear inflammation is thought to be a major contributor to the development of hearing loss and balance disorders. We report the results of the in vivo characterization of cochlear tissues inflammation induced by noise exposure or injection of bacterial lipopolysaccharide in two rodent species. The anaesthetized animals were scanned using a 4.7T MRI system. The calculated signal enhancement due to the observed uptake of a contrast agent was greater on inflamed than normal cochleae. MR findings correlated well with immunohistochemistry. We suggest that increase in gadodiamide uptake occurred as a consequence of increased vascular permeability.