Reliability of preoperative gel foam patch test in predicting postoperative hearing outcome

Abstract

Aim: This study aims to know the correlation between the preoperative gel foam patch test with the postoperative hearing outcome. Objectives: The objective is to correlate and compare the air-bone gap (ABG) and mean hearing thresholds obtained at frequencies 500 Hz, 1 KHz, 2 KHz, and 4 KHz through audiological evaluation preoperatively, immediately after gelfoam application and 2 months postoperatively (Type I tympanoplasty). Materials and Methods: A total of 124 cases with a mean age of 37 years with a history of chronic otitis media (COM, mucosal type) having medium to large size of central perforation of the tympanic membrane with pure conductive hearing loss participated in this study. Cases were subjected to routine investigations along with a battery of otological investigations. Further, pure-tone audiometric evaluation was performed before gelfoam patch application, immediately after gelfoam patch application and postoperatively after 2 months and the outcomes were compared. Results: Across all four frequencies, ABG was improved and showed a highly significant difference between preoperative mean findings in comparison to patch and postoperative findings. In this study, a strong positive correlation and reliability between patch test hearing thresholds and postoperative hearing thresholds are observed. Comparing preoperative hearing thresholds and postoperative hearing thresholds with student t-test thresholds improved by approx 17 dB hearing loss (17.50645). Conclusion: Hence, this study shows preoperative gel foam patch test in cases of pure conductive hearing loss is reliable in predicting the postoperative hearing outcome. Furthermore helps in convincing and counseling the patients.