Bilateral stapedectomy: association between first- and second-ear surgical findings and their effects on the...

We assessed the association between first-ear and second-ear surgical findings in patients undergoing second-ear stapedectomy for bilateral otosclerosis and the impact of such findings on the audiometric outcome of the second ear.

A retrospective chart review of all stapedectomy patients who underwent stapes surgery by one of two surgeons in a single tertiary referral institution from 1962 to 2001 was performed, and those patients who underwent bilateral stapedectomy were identified. Patient demographic data, surgical findings, procedure performed, and preoperative and postoperative audiometric data were recorded.

A total of 459 patients (918 ears) underwent bilateral stapedectomy for bilateral otosclerosis during the study period, of whom 426 had complete data for analysis. The finding of a white or obliterated footplate in the second ear was significantly higher if the first ear had this disease manifestation (p < .001, chi2 test). The association between a second drill-out's being performed and a drill-out in the first operation was significant (p < .001, chi2 test). Statistical analysis identified that those who underwent a drill-out procedure had a 2.9-fold increase in unsuccessful outcome in comparison to those who did not have a drill-out (odds ratio, 2.89; 95% confidence interval, 1.41 to 5.89). Facial nerve anomalies were infrequently encountered, affecting only 23 patients, of whom 3 had bilateral abnormalities. The finding of an overhanging or dehiscent facial nerve in the second ear was significantly more likely if such an abnormality was identified during the first procedure (23% versus 2.5%; p = .005, Fisher's exact test).

Second-ear hearing results are poorer in those who require a drill-out of this ear, and this is more likely to be required if a drill-out was required in the first ear, regardless of a successful outcome of the first procedure. Patients should be aware of the reduced likelihood of success in these cases and be counseled regarding risks and benefits of second-ear surgery based, in part, on the findings from the first ear. This study confirms that bilateral advanced footplate obliteration and overhanging or dehiscent facial nerves may be anticipated in patients found to have these abnormalities during first-ear stapedectomy.