Eustachian Tube Function and Mastoid Pneumatization as Prognostic Factors of Type 1 Tympanoplasty

Kim, Yong Hyun; Maeng, Jin Woo; Kim, Hyung Jong

Abstract

BACKGROUND AND OBJECTIVES
Pre-operative eustachian tube function (ETF) and mastoid aeration are important in maintaining a post-operative aerated middle ear. In this study, we evaluated the prognostic value of pre-operative ETF and of mastoid aeration predicting post-operative outcomes after chronic otitis media surgery.
SUBJECTS AND METHOD
One hundred eighty patients of non-cholesteatomatous chronic otitis media who underwent type 1 tympanoplasty were categorized into two groups (well-patent ETF versus obstructed ETF) according to the results of Valsalva maneuver test, and also categorized into four groups according to the results of a modified pressure inflation-deflation equilibration test. The extent of mastoid aeration was measured using high resolution computerized tomography scan of the temporal bone and image analysis software (Rapidia(R)). The post-operative outcomes at 3 months of surgery were compared with those of the tympanoplasty only group and the mastoidectomy with tympanoplasty (MT) group as well as with the different pre-operative ETF groups.
RESULTS
Successful post-operative outcome was 87.9% in the well-patent ETF group and 82.8% in the obstructed ETF group according to the Valsalva maneuver test (p=0.418). Successful outcome was 90.6% in the good ETF group and 74.5% in the poor ETF group according to the modified pressure equilibration inflation-deflation test, which was significantly different (p=0.047). Patients with successful outcome had greater extent of mastoid aeration than those with poor surgical outcome (p=0.026). Distributions of surgical outcome were not statistically different between the tympanoplasty only group and the MT group (p>0.05).
CONCLUSION
The ETF measured by modified pressure inflation-deflation equilibration test and the extent of mastoid aeration measured using the Rapidia(R) program were valuable information that can be used to predict post-operative outcomes after chronic otitis media surgery.