Nystagmus in patients with unilateral acute otitis media complicated by serous labyrinthitis

Conclusion The patients with serous labyrinthitis caused by acute otitis media (AOM) exhibited various patterns of nystagmus in which direction-fixed irritative-type nystagmus was the most common pattern. Differential effects on inner ear function by toxic or inflammatory mediators may be responsible for the various manifestation of nystagmus. Objective This study aimed to investigate nystagmus patterns in patients with serous labyrinthitis, and discuss possible mechanisms. Methods From October 2011 to March 2014, 13 consecutive patients with serous labyrinthitis were included. Eye movements of the patients were serially examined using video-nystagmography, and patterns of nystagmus were investigated. Results The most commonly observed pattern was direction-fixed nystagmus (nine of 13 patients). Of these, eight showed irritative-type, and one showed paretic-type. Direction of nystagmus, although the intensity gradually decreased, was not changed during the course of treatment. One patient showed direction-changing spontaneous nystagmus, which changed into paretic-type direction-fixed nystagmus 1 day after myringotomy. Three patients exhibited persistent direction-changing positional nystagmus in a supine head-roll test. Of them, two showed apogeotropic and one showed geotropic type. In all 13 patients, vertigo and hearing loss were improved after the treatment.