Nystagmus in adult patients with acute otitis media or otitis media with effusion without dizziness.

The present study aimed to investigate the incidence and patterns of nystagmus in adult patients with acute otitis media (AOM) or otitis media with effusion (OME) without dizziness or vertigo, and discuss possible mechanisms. From February 2018 to November 2018, 34 consecutive patients with AOM or OME without dizziness were included. Nystagmus was examined with video Frenzel glasses. Of 34 adult AOM or OME patients without dizziness, nystagmus was observed in 28 patients (82%). In unilateral AOM or OME (n = 30), the most commonly observed nystagmus pattern was irritative-type direction-fixed nystagmus (n = 13), followed by paretic-type direction-fixed nystagmus (n = 8), and direction-changing positional nystagmus (n = 4). In bilateral AOM or OME (n = 4), direction-fixed nystagmus and direction-changing positional nystagmus were observed in two and one patients, respectively. Nystagmus was observed in as many as 82% of adult AOM or OME patients even though they did not complain of dizziness, and the pattern of nystagmus was either direction-fixed or direction-changing. Direct effect of inflammatory mediators penetrated from the middle ear and biochemical alteration in the inner ear fluids due to blood-perilymph barrier dysfunction may result in the presence of nystagmus in AOM or OME patients without dizziness.