Evaluation of the Middle Ear Risk Index (MERI) as a prognostic tool in cases of tympanoplasty with mastoidectomy

Abstract

Abstract Background Chronic suppurative otitis media (CSOM) is a long-standing inflammation of the middle ear mucosa characterized by tympanic membrane perforation and persistent or intermittent otorrhea (discharge lasting a minimum of 2–6 weeks). Our study aimed to assess the middle ear risk index as a prognostic tool in tympanoplasty with mastoidectomy cases. Methods This single-center prospective observational study was performed at a tertiary care center from May 2024 to May 2025 comprising 60 patients with non-complicated safe CSOM candidate for post-auricular canal wall-up (CWU) tympanomastoidectomy through a post-auricular approach. Patients were assigned according to Austin-Kartush classification. All patients underwent multislice CT scan and pure tone audiometry (PTA). Results Hearing improvement was achieved in 39 (65%) patients, and successful graft uptake occurred in 45 (75%). Higher MERI scores were associated with poorer postoperative hearing outcomes. Spearman correlation demonstrated a significant negative association between MERI score and hearing improvement ( r = − 0.385, p = 0.002). On multivariate logistic regression analysis, MERI score emerged as the only independent predictor of hearing improvement (OR = 0.600, 95% CI: 0.370–0.990, p = 0.048). Conclusions Elevated MERI scores were significantly associated with unfavorable anatomical and functional outcomes, whereas lower scores correlated with successful graft uptake and greater hearing improvement.