Sudden sensorineural hearing loss with intralabyrinthine hemorrhage after COVID-19 vaccination.

Otologic symptoms of sudden sensorineural hearing loss (SSNHL) have been reported after Coronavirus disease 2019 (COVID-19) vaccinations. However, the association between SSNHL and COVID-19 vaccination has not been clearly established. SSNHL with vertigo can be induced by intralabyrinthine hemorrhage (ILH). The case of a 61-year-old female who was diagnosed SSNHL with ILH after COVID-19 vaccination is presented here. She visited the emergency department for left sudden hearing loss and vertigo that had occurred the previous day. She had received a third booster COVID-19 mRNA vaccination one day prior to the visit; symptoms occurred 6 hours after vaccination. On pure tone audiometry, her hearing threshold indicated deafness in the left ear. A lesion assumed to be ILH was observed on temporal magnetic resonance imaging. She received an oral steroid followed by salvage treatment with intratympanic steroid injection. Three months after symptom onset, her hearing threshold remained deaf with slight improvement at low frequencies in the left ear. Because the symptoms of and prognosis for SSNHL may be worse and vertigo may occur in patients with SSNHL and ILH, careful treatment is required.