Influence of Ossicular Chain Damage on Hearing After Chronic Otitis Media and Cholesteatoma Surgery: A Systematic Review and Meta-analysis.

IMPORTANCE Physicians should ideally be able to provide patients with chronic otitis media and/or cholesteatoma specific information about postoperative hearing outcome, based on their level of preoperative ossicular chain damage (OCD). OBJECTIVE To identify the influence of preoperative OCD on hearing outcomes in patients after chronic otitis media and/or cholesteatoma surgery. DATA SOURCES PubMed, EMBASE, and the Cochrane Library databases were systematically searched for available evidence, without any constraints, on December 13, 2014, for articles published between January 1, 1975, and December 13, 2014. STUDY SELECTION We reviewed the literature for articles assessing the prognostic value of OCD on postoperative hearing outcome (air-bone gap [ABG] in decibels), using Austin-Kartush criteria or independent OCD classification systems. We assessed relevance and validity using a self-designed critical appraisal tool based on the Cochrane Collaboration's risk of bias tool. DATA EXTRACTION Characteristics of study populations and postoperative ABGs in decibels were extracted from all included studies by 4 authors (E.F.B., M.N.G., N.J.K., A.S.H.J.L.). RESULTS The tested hypothesis was formulated before data collection. Primary study outcome was defined as postoperative adult hearing outcomes after COM and/or cholesteatoma surgery defined as mean postoperative ABG. Our search yielded 5661 articles. Nine articles with high relevance were included. Pooled results of studies using the Austin-Kartush criteria showed a significant (P < .001) difference in mean ABG in favor of group B, when comparing group B (patients with malleus present, stapes absent; 11.1 [95% CI, 10.3-11.8] dB) to group C (patients with malleus absent, stapes present; 15.7 [95% CI, 14.6-16.7] dB) and group B to group D (patients with malleus absent, stapes absent; 16.5 [95% CI, 15.2-17.9] dB). Three studies using independent OCD classification criteria found no influence of stapes structure (intact stapes suprastructure, 13.5 [95% CI, 10.3-16.7], 15.1 [95% CI, 11.8-18.3], and 21.9 [95% CI, 15.0-28.8] dB vs absent stapes structure, 12.8 [95% CI, 9.5-16.1], 19.5 [95% CI, 14.9-24.1], and 30.2 [95% CI, 24.7-35.8] dB) on postoperative ABG. One study reported a significant (P = .04) difference in mean ABG between patients with present (18.9 [95% CI, 15.7-22.1] dB) and absent (24.4 [95% CI, 20.2-28.6] dB) malleus. CONCLUSIONS AND RELEVANCE Pooled results of Austin-Kartush studies showed that in patients with COM, with or without cholesteatoma, the malleus status is a significant predictor of postoperative hearing outcome, independent of the stapes condition. Studies reporting on individual ossicle status supported this finding by showing that only malleus condition influenced postoperative hearing outcome. These findings are based on level IV evidence, which indicates the need for future high-level evidence studies.