Results of hearing tests after total middle ear reconstruction

Patients treated by mastoidectomy in the past often present with hearing loss and cavity problems such as pus discharge. Total middle ear reconstruction (TMER) improves the hearing of these patients by correcting cavity problems and resolution of ear discharge, which facilitates ossicular chain reconstruction such as type III or type IV tympanoplasty.

To evaluate the effectiveness of TMER in improving hearing.

We reviewed the audiograms of 56 ears of 48 patients who underwent TMER in combination with either type III or type IV tympanoplasty. Audiometric pure tone thresholds averaged over three frequencies (500, 1000, and 2000, pure tone average) were measured and compared before and after surgery. Successful outcome was defined as improvement of 15 dB or more. The mean follow-up was 5.7 years (range 1.1-12.6). We also analyzed the relations between hearing improvement and factors such as type of tympanoplasty (types III and IV), choice between one-stage and two-stage operation, and the interval between original mastoidectomy and final operation.

The mean hearing gain was 13.6 (+/-11.9) dB. Twenty-seven procedures (48.2%) were considered successful, with improvement of 15 dB or more. The results of type III tympanoplasty group were significantly superior to those of type IV (p<0.05, Student's t test). One- and two-stage surgery did not significantly influence outcome. The interval between the initial operation correlated weakly and negatively (r = - 0.266, p<0.05) with hearing gain.