Magnetic resonance imaging findings in idiopathic sudden sensorineural hearing loss

Background: The unpredictability in presenting signs and symptoms of idiopathic sudden sensorineural hearing loss (SSNHL) presents a notable diagnostic challenge for clinicians. Previous studies have confirmed the potentially important role of magnetic resonance imaging (MRI) in the diagnosis and prognostication of idiopathic SSNHL to guide definitive medical therapy, but correlations of these findings with outcomes remain controversial. Purpose: To evaluate and identify magnetic resonance imaging (MRI) findings associated with idiopathic sudden sensorineural hearing loss (SSNHL). Material and Methods: Sixty-eight patients with a documented diagnosis of idiopathic SSNHL and 20 controls underwent 1.5-T or 3-T MRI of the brain. Age, gender, ethnicity, associated co-morbidities, and audiometry findings were also recorded. Statistical analysis was performed to compare outcome measures between idiopathic SSNHL and control groups. Results: The mean age of the cohort was 57 ± 17 years, with a male-to-female ratio of 1:1.1. MRI findings include 25.0% (P = 1.000) with chronic microangiopathic disease, 14.7% (P = 0.165) with temporal bone aberrations, 13.2% (P = 0.165) with facial and/or vestibulocochlear nerve complex changes, 11.8% (P = 1.000) with venous malformations, 8.8% (P = 0.104) with arterial malformations, and 8.8% (P = 0.184) with cerebral and/or brainstem parenchymal disease. Conclusion: Arteriovenous malformations and central neurologic disease are not directly associated with idiopathic SSNHL on MRI. However, visualized signal changes of inner ear structures and facial/vestibulocochlear nerve complex support previously postulated theories, which include viral as well as inflammatory processes in the development of idiopathic SSNHL.