Manganese enhanced magnetic resonance imaging (MEMRI): A powerful new imaging method to study tinnitus

• Published in: Hearing research 2014-05, Vol.311, p.49-62
• Main Authors: Cacace, Anthony T., Brozoski, Tom, Berkowitz, Bruce, Bauer, Carol, Odintsov, Boris, Bergkvist, Magnus, Castracane, James, Zhang, Jinsheng, Holt, Avril Genene
• Format: Article
• Language: English
• Subjects: Animals; Auditory Perception; Brain - metabolism; Brain - physiopathology; Calcium Channels - metabolism; Contrast Media - adverse effects; Contrast Media - metabolism; Disease Models, Animal; Humans; Ion Channel Gating; Magnetic Resonance Imaging - methods; Manganese - adverse effects; Manganese - metabolism; Membrane Potentials; Noise; Predictive Value of Tests; Salicylates; Tinnitus - diagnosis; Tinnitus - etiology; Tinnitus - metabolism; Tinnitus - physiopathology; Tinnitus - psychology
• ISSN: 0378-5955; 1878-5891
• DOI: 10.1016/j.heares.2014.02.003

Manganese enhanced magnetic resonance imaging (MEMRI) is a method used primarily in basic science experiments to advance the understanding of information processing in central nervous system pathways. With this mechanistic approach, manganese (Mn2+) acts as a calcium surrogate, whereby voltage-gated calcium channels allow for activity driven entry of Mn2+ into neurons. The detection and quantification of neuronal activity via Mn2+ accumulation is facilitated by “hemodynamic-independent contrast” using high resolution MRI scans. This review emphasizes initial efforts to-date in the development and application of MEMRI for evaluating tinnitus (the perception of sound in the absence of overt acoustic stimulation). Perspectives from leaders in the field highlight MEMRI related studies by comparing and contrasting this technique when tinnitus is induced by high-level noise exposure and salicylate administration. Together, these studies underscore the considerable potential of MEMRI for advancing the field of auditory neuroscience in general and tinnitus research in particular. Because of the technical and functional gaps that are filled by this method and the prospect that human studies are on the near horizon, MEMRI should be of considerable interest to the auditory research community. This article is part of a Special Issue entitled . •Manganese enhanced MRI (MEMRI) is a powerful new imaging modality to study tinnitus.•Voltage-gated calcium channels allow Mn2+entry which is retained by active neurons.•MEMRI allows for longitudinal probing of neuronal function independent of blood flow.•MEMRI is unaffected by scanner noise.•Customized nanoparticle constructs may have direct utility to tinnitus research.