KHẢO SÁT KHOẢNG CÁCH TỪ NGÀNH DÀI XƯƠNG ĐE ĐẾN ĐẾ BÀN ĐẠP TRÊN CT SCAN VÀ ĐỐI CHIẾU TRONG PHẪU THUẬT THAY THẾ XƯƠNG BÀN ĐẠP ĐIỀU TRỊ BỆNH XỐP XƠ TAI

Abstract

Objective: To assess the distance from the long process of the incus to the stapes footplate on computed tomography (CT) and compare it with intraoperative measurements during stapes replacement surgery for otosclerosis. Materials and Methods: A prospective, descriptive cross-sectional study was conducted on 49 patients with otosclerosis who underwent stapes surgery at Ho Chi Minh City Ear-Nose-Throat Hospital between January and August 2025. Preoperative CT measurements of the incus-to-footplate distance were obtained on both the ngang - xương bàn đạp plane and the đứng ngang - xiên plane. Intraoperative distances were recorded and compared with imaging findings. Results: Forty-nine patients were analyzed. On CT, the mean distance from the incus to the lateral surface of the stapes footplate was 4.06 ± 0.25 mm on the axial plane and 4.02 ± 0.26 mm on the đứng ngang - xiên plane. The corresponding distances to the medial surface were 4.60 ± 0.22 mm and 4.59 ± 0.21 mm, respectively. Strong correlations were observed between the two imaging planes (r₁ = 0.924, r₂ = 0.863; both p < 0.001). Intraoperative measurements showed median incus-to-footplate distances of 4.25 mm [IQR, 4.00–4.25] in group 1 (from the incus to the lateral surface of the stapes footplate) and 4.50 mm [IQR, 4.25–4.50] in group 2 (from the incus to the medial surface of the stapes footplate). Comparison with intraoperative values demonstrated no statistically significant difference for the axial plane in group 1 (p >0,05). Conclusion: The distance betwen incus and the lateral surface of the stapes footplate measured on the ngang - xương bàn đạp plane by CT shows strong agreement with intraoperative findings. This suggests that axial plane CT measurements may provide a reliable preoperative estimate for prosthesis length in stapes surgery.