This potentially allows a more precise depiction of the membranous structures of the inner-ear such as Reissner’s membrane, macula and basilar membrane that are crucial to evaluate the patient’s condition.

While the aforementioned studies on structural imaging of the inner-ear were performed on clinical MR scanners at 1.5T or 3T, going to ultra-high MR (B 0 ≥ 7T) leads to an increased signal-to-noise ratio (SNR) and improved spatial resolutions. For example, endolymphatic hydrops, that are a disorder of the inner-ear associated with Meniere’s disease, can be imaged with high contrast with respect to the surrounding tissues using gadolinium-based contrast-agents. MR imaging of this region may contribute to a reliable diagnostic of health deficit as for Menieres’ disease or hearing loss. The cochlea, together with the semi-circular ducts (vestibular system) form the inner-ear. A better understanding of how the frequency representations are modified by hearing loss or Meniere’s disease would help facilitate diagnosis and help the audiologists or the otorhinolaryngologist to orient the patient to an efficient pharmacological or cognitive treatment. However, none of the aforementioned studies above investigated simultaneously the tonotopic gradient reorganization within the other auditory relays. the frequency lost at the cochlear level). In hearing impaired humans, the damages concomitant with hearing loss or Meniere’s disease at the level of the cochlea has been reported to induce a broadening of the auditory filters at the cochlear level and then an enlargement of the cortical representations near the “lesion-edge” frequency (i.e. In a normal subject, the auditory information is decomposed at the level of the cochlea according to its frequency in a specific organization named cochleotopy–or tonotopy–, where low and high frequencies activate hair cells in the center and at the base of the cochlea, respectively.ĭue to the increased SNR and spatial resolution at 7T, fMRI studies focusing on each of the auditory relays separately have consistently reported that the cochlear frequency decomposition is conveyed as a clear, specific frequency gradient ranging from low to high frequencies in all the different subcortical auditory structures (collicular nuclei and Superior Olivary Complex:, inferior colliculi: and medial geniculate bodies: ), until the auditory cortices. Despite a large number of studies investigating the auditory relays in healthy subjects such as the Cochlear Nuclei:, the Inferior Colliculi:, the Medial Geniculate Bodies:, the Auditory Cortices:, or in tinnitus, little is known on how hearing loss or Menieres’ disease modify functional representations along the human auditory pathway.

Auditory signal path