Pneumolabyrinth with Labyrinthitis as the Suspected Cause.

Pneumolabyrinth is a rare condition with air bubbles existing in the vestibule and/or cochlea. We report a case of pneumolabyrinth without trauma that was suspected to be caused by labyrinthitis. A 65-year-old man presented with vertigo and hearing loss in the left ear after catching a cold. Computed tomography performed after there had been no improvement in the patient's symptoms showed the presence of air bubbles in the vestibule, semicircular canals and cochlea. The patient was transferred to our hospital with suspected perilymphatic fistula. Bacterial infection was suspected after the laboratory tests had indicated a severe inflammatory response, and the patient was treated with antibiotics. However, no bacteria were detected in a bacterial culture of the otorrhea. An exploratory tympanotomy was performed to improve the patient's staggering gait and to examine the middle ear, with no obvious fistula being observed. Subsequent fenestration of the round window revealed a white mass that appeared to contain bacteria which was collected from the cochlea and submitted for analysis and bacterial culture. However, no bacteria were detected and the mass contained white blood cells. We suspected pneumolabyrinth following labyrinth infection. However, the cause of air bubble formation remains unclear and needs to be validated with further research.