[High-resolution computed tomography imaging features and endoscopic surgical outcomes of congenital ossicular chain malformation with concomitant external auditory canal stenosis].

Objective: To investigate the high-resolution CT (HRCT) imaging characteristics and endoscopic surgical outcomes in patients with congenital ossicular chain malformation and concomitant external auditory canal stenosis. Methods: The clinical data from congenital ossicular chain malformation patients with concomitant external auditory canal stenosis who were admitted to the Eye and ENT Hospital of Fudan University between July 2017 and March 2025 were retrospectively analyzed. The clinical presentations, HRCT findings, endoscopic examinations, and postoperative follow-up results were summarized. Results: A total of 54 patients (58 ears) aged [M (Q1, Q3)] 18.5 (12.0, 26.3) years were included, with 29 males and 25 females. The diagnostic concordance rates of HRCT for detecting incus, malleus, and stapes defects were 96.6% (56/58), 94.8% (55/58), and 53.4% (31/58), respectively. HRCT identified severe bony segment stenosis in 7 cases (12.1%) and mild bony segment stenosis in 35 cases (60.3%), whereas otoendoscopy revealed partially visualized stenosis in 16 cases (27.6%). Of the 58 affected ears, 44 underwent concurrent artificial ossicular implantation and external auditory canal reconstruction. Postoperative audiometric assessments at 3 to 12 months demonstrated statistically significant reductions in mean air conduction thresholds [(37.1±18.3) decibel hearing level (dB HL) vs (61.7±12.7) dB HL, P<0.001], mean bone conduction thresholds [(18.5±12.3) dB HL vs (26.3±9.5) dB HL, P=0.001], and air-bone gaps [(18.8±7.8) dB HL vs (35.3±9.6) dB HL, P<0.001] compared with preoperative measurements. Conclusions: The integrated application of HRCT and otoendoscopy enables effective evaluation of the anatomical characteristics of ossicular chain malformation and external auditory canal stenosis. Concurrent ossicular chain reconstruction and external auditory canal reconstruction results in significant improvements in auditory outcomes.