Assessment of complications of the condition and of the treatment of otitis media with effusion.

Persistent otitis media with effusion (OME) may cause long-term changes of the tympanic membrane and middle ear, resulting in some degree of hearing loss. One of the traditional aims of treatment with ventilation tubes is to prevent these complications from developing. Ventilation tubes themselves, however, are also known to induce changes of the tympanic membrane. Several recent studies have addressed the questions: what are the effects of the disease, and what are the result of its treatment? The object of this study was to present the state of the art, by literature review, regarding structural and functional complications of OME and treatment with ventilation tubes. In both observational and experimental studies tympanosclerosis is reported to occur in 39-65% of ears treated with ventilation tubes as opposed to 0-10% of untreated ears. For segmental atrophy these percentages are 16-73 and 5-31, respectively. Regarding the prevalence of atelectasis and attic retraction, the difference between ventilated and untreated ears is less: 10-37% as opposed to 1-20% for atelectasis, and 10-52% as opposed to 29-40% for attic retraction. The average hearing loss associated with these tympanic membrane abnormalities is less than 5 dB. Although ventilation tubes have proven very effective in improving hearing in the short term, they have not proven effective in preventing long-term changes of the tympanic membrane related to OME, nor in keeping some degree of hearing loss from developing.