Eustachian Tube Obstruction Grade as an Independent Determinant of Audiological and Quality-of-Life Outcomes in Pediatric Chronic Adenoiditis: A Retrospective Cohort Study.

Background and Objectives: Eustachian tube (ET) dysfunction links adenoidal disease to persistent middle ear dysfunction in children, yet the independent contribution of ET orifice obstruction grade to audiological outcomes and health-related quality of life remains unquantified after adjustment for anatomical and inflammatory confounders. Because conventional anatomical grading (e.g., the Cassano classification) does not directly characterize the degree of ET orifice compromise, it may underestimate the functional threat to middle ear ventilation; this study is the first to quantify the independent predictive value of endoscopic ET obstruction grade. This study aimed to evaluate ET obstruction grade as an independent determinant of hearing thresholds, middle ear pressure, and quality-of-life impairment in children with chronic adenoiditis and otitis media with effusion. Materials and Methods: A retrospective cohort of 236 children (aged 3-12 years) was analyzed. ET orifice obstruction was graded endoscopically as none, partial, or complete. Primary outcomes included pure tone average (PTA), middle ear pressure (MEP), and OSA-18 total score. Multivariate linear and logistic regression models were fitted, adjusting for age, sex, Cassano grade, neutrophil-to-lymphocyte ratio (NLR), allergic status, and acute otitis media frequency. The modifying role of mucosal appearance (edematous versus fibrotic/remodeling) on quality-of-life outcomes was also assessed. Results: ET obstruction was absent in 42 (17.8%), partial in 114 (48.3%), and complete in 80 (33.9%) children. PTA increased progressively across groups (22.2 ± 5.5 to 36.2 ± 6.7 dB; p < 0.001), as did OSA-18 scores (44.9 ± 7.9 to 80.4 ± 10.3; p < 0.001). In adjusted analysis, each obstruction increment independently predicted a 5.57 dB PTA increase (95% CI 4.37-6.77; p < 0.001), a 14.89-point OSA-18 increase (95% CI 12.87-16.92; p < 0.001), and 5.12-fold higher odds of PTA > 30 dB (95% CI 2.84-9.24; p < 0.001). Persistent middle ear dysfunction at six months occurred in 7.1%, 26.3%, and 61.3% across obstruction grades. Among children with complete obstruction, fibrotic mucosa was associated with higher OSA-18 scores than edematous mucosa (82.3 vs. 76.8; p = 0.02). Conclusions: ET obstruction grade independently determines audiological and quality-of-life outcomes in pediatric chronic adenoiditis. Mucosal remodeling further amplifies quality-of-life burden in complete obstruction. These findings support routine ET endoscopic grading in pediatric otorhinolaryngology risk stratification.