The present study aims at grouping the perforations of the tympanic membrane according to their precisely calculated sizes, in view of a subsequent establishment of hearing loss variation with such sizes; these data permit to appreciate the extent to which the initial size of the perforation influences the audiometric gain, after the successful closing of the perforation.
Materials and method: The retrospective study included 148 patients whose unique pathology was perforation of the middle ear. The perforations were photographed and measured as ratio of tympanic membrane’s area; the auditive losses were recorded on audiograms, both initially and after healing of the perforations. The difference between the auditive thresholds in aerial and bone conduction, and the air bone gap (ABG) were calculated prior to surgery, on each of the low, average and high frequencies. The patients selected for the study were divided into 4 groups, according to the perforations size, the obtained data being statistically analyzed.
Results: The correlations between the 4 groups of dimensions of perforations and hearing loss showed the latter’s dependence on frequencies. For perforations affecting less that 10% of the tympan, hearing loss and the post-operative audiological gain do not depend on the size of the perforation while, for the rest of perforations, both hearing loss and auditive recovery increase with the sizes of tympan defects. The highest audiometric gain was registered on low frequencies, whereas auditive recovery on high frequencies was not spectacular. Conclusions: Perforations of tympanic membrane should be measured with high precision and grouped according to their sizes, for subsequent establishment of the clinical and therapeutical measures to be taken, as well as for a correct estimation of the success of perforations closing.
- perforation of tympanic membrane