The effects of chronic otitis media with effusion on the measurement of distortion products of otoacoustic emissions: presurgical and postsurgical examination.

This study aims to determine the influence of middle ear effusion and inserted tympanostomy tubes on the feasibility of recording and of the amplitude of distortion product otoacoustic emissions (DPOAE). Effusion in the middle ear reduces the number of measurable responses and their amplitude in the whole range of frequencies from 0.5 to 8 kHz. These changes were more distinct in mucous than in serous effusion. There was an increase in the number of measurable responses and amplitude of DPOAE after surgery. Inserted tympanostomy tubes have no influence on the feasibility of DPOAE recording but reduce their amplitude in comparison to the control group.