MAGNETIC RESONANCE IMAGING FINDINGS IN SUDDEN SENSORINEURAL HEARING LOSS

Objective: To investigate the role of magnetic resonance imaging (MRI) in the diagnosis of sudden sensorineural hearing loss (SSNHL). Methods: Fifty-four consecutive patients affected by SSNHL were investigated using brain MRI. MRI was performed with an eight-channel phased-array head coil to study the entire audiovestibular pathway and the whole brain. The protocol study consisted of a high-resolution study of the temporal bone, internal auditory canal (IAC), cerebellopontine angle (CPA), and brainstem combining 2 mm thin-slice axial T(2)-weighted two-dimensional fast spin echo (FSE) and fluid-attenuated inversion recovery (FLAIR) sequences, pre- and postcontrast (gadolinium-diethylenetriamine pentaacetic acid) administration fat-suppressed axial T(1)-weighted two-dimensional FSE sequences, and a T(2)*-weighted three-dimensional Fourier transformation-constructive interference in steady state sequence (FT-CISS) , with 0.4 mm ultrathin partitions. The rest of the brain was studied with a 4 mm axial T(2)-weighted FLAIR sequence. Results: Thirty-one of 54 (57%) cases of SSNHL presented with MRI abnormalities. In 6 of 54 cases, the detected abnormality was directly correlated to the clinical picture (2 labyrinthine hemorrhage, 1 cochlear inflammation, 1 acoustic neuroma, 1 arachnoid cyst of the CPA, and 1 case of white matter lesions in the pons, compatible with demyelinating plaques along the central audiovestibular nervous pathway, as the first expression of multiple sclerosis). Conclusions: An extensive MRI study of the audiovestibular nervous pathway and of the whole brain, pre- and postparamagnetic contrast administration, is recommended to rule out the wide spectrum of abnormalities that can cause SSNHL.