Mixed hearing loss in iatrogenic tympanic membrane perforations over the round window niche and the immediate effect of paper patch myringoplasty.

OBJECTIVES

Report the immediate audiologic effect of paper patch myringoplasty to repair iatrogenic tympanic membrane perforations directly over the round window.

METHODS

Retrospective case-control study of 15 patients treated for inner ear disease with a MicroWick and dexamethasone for 1 month, resulting in 2-mm perforations over the round window. Paper patch myringoplasties were performed to repair the perforations. Audiograms were performed before and immediately after the paper patch myringoplasty.

RESULTS

After paper patch placement, there was a significant improvement in air-bone gap at 250 (p < 0.001), 500 (p = 0.003), and 1000 Hz (p = 0.004) and a significant improvement in bone conduction (BC) threshold at 250 (p = 0.002), 500 (p < 0.001), 1000 (p = 0.002), 2000 (p = 0.003), and 3000 Hz (p = 0.02).

CONCLUSIONS

Paper patch myringoplasty improves both air conduction and BC hearing from small perforations over the round window. The decrease in BC hearing is a result of middle ear mechanics and is not a true sensorineural hearing loss.