CT imaging parameters of the oval window region can predict the extent of stapes footplate exposure in patients with otosclerosis

BACKGROUND: Stapedotomy, including classic stapedotomy (CS) and reversed stapedotomy (RS), is the primary surgery for otosclerosis. RS is preferred when the stapes suprastructure is preserved and footplate exposure is adequate. OBJECTIVES: To explore the correlation between stapes footplate exposure and CT imaging parameters of the oval window region, and assess their value in preoperative surgical planning. MATERIALS AND METHODS: A retrospective study of 166 otosclerosis surgeries (105 RS, 61 CS) performed by a single senior surgeon (2018-2025) was conducted. Reconstructed preoperative temporal bone HRCT scans with multiplanar reconstructions were used to measure the relative positions of the stapes and its surrounding structures, followed by analysis of their predictive value for surgical selection. RESULTS: Between the two groups, postoperative hearing outcomes were comparable, while the CS group had a higher incidence of floating footplate. Stapes footplate width (SFW) and distance between the facial nerve and the long axis of the stapes (FNSL) emerged as independent predictors, with respective cutoffs of 1.13 mm and 0.73 mm. CONCLUSION AND SIGNIFICANCE: RS yields fewer surgical complications. Preoperative HRCT measurements of SFW and FNSL can predict the degree of stapes footplate exposure and facilitate preoperative surgical planning.