Imaging in Audiology
The imaging of auditory structures faces limitations posed by the location of the inner ear, requiring a combination of high-resolution computed tomography and magnetic resonance imaging (MRI). Functional imaging faces limitations posed by the adverse acoustic environment during MRI scanning, and requires a combination of passive and active noise cancellation to provide low-noise measurements. Generally speaking, up to now MRI equipment has not adequately catered for the requirements of audiological testing. Positron emission tomography (PET) scans provide a quiet environment but suffer from low spatial resolution and the need to average across participants. Functional MRI (fMRI) in high magnetic fields will allow measurements of cortical tonotopic map reorganization and provide important information about the central aspects of hearing disorders. Diffusion tensor imaging in combination with fMRI offers a currently untapped potential to study central auditory processing disorders. Simultaneous electroencephalography (EEG), evoked potentials and fMRI in audiology is feasible and allows millisecond temporal resolution and millimeter spatial resolution; this approach may provide another combination technique for probing central auditory processing disorders.
KeywordsHair Cell Diffusion Tensor Imaging Auditory Cortex Cochlear Implant Auditory Nerve
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