Yanqing Fang1,2,3, Kun Zhang1,2,3, Liu-Jie Ren1,2,3, J J Lamb4, Rujian Hong5, Yilai Shu6,7,8, Bing Chen9,10,11. 1. Department of the Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, ENT Institute and Otorhinolaryngology, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, 200031, China. 2. Institutes of Biomedical Sciences, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, 200032, China. 3. NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China. 4. Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA. 5. Department of Radiology, Eye and ENT Hospital, Fudan University, Shanghai, 200031, China. 6. Department of the Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, ENT Institute and Otorhinolaryngology, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, 200031, China. yilai_shu@fudan.edu.cn. 7. Institutes of Biomedical Sciences, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, 200032, China. yilai_shu@fudan.edu.cn. 8. NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China. yilai_shu@fudan.edu.cn. 9. Department of the Affiliated Eye and ENT Hospital, State Key Laboratory of Medical Neurobiology, ENT Institute and Otorhinolaryngology, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, 200031, China. bingchen@fudan.edu.cn. 10. Institutes of Biomedical Sciences, Fudan University, 83 Fenyang Road, Xuhui District, Shanghai, 200032, China. bingchen@fudan.edu.cn. 11. NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China. bingchen@fudan.edu.cn.
Abstract
PURPOSE: The aims of this article are: (1) is there an ideal incudostapedial joint (ISJ) angle after stapedotomy? (2) is there any difference between pre- and postoperative ISJ angle? and (3) what is the significance of the ISJ angle in postoperative hearing outcomes? METHODS: Forty six ears from 39 different adult patients (28 women and 11 men; 21 left and 25 right ears) with a mean age of 39 years with clinical otosclerosis who underwent stapedotomy between May 2017 and May 2019 were retrospectively registered, including seven bilateral surgery cases. ISJ angle and intravestibular depth of the stapes prosthesis were measured from multiple planar reconstruction-computed tomography images and the length of the prosthesis was measured during surgery. Relationships between the ISJ angle parameters and postoperative hearing outcomes and parameters of the prosthesis were analyzed. RESULTS: The mean ISJ angle was 93.3° ± 8.8° preoperatively and 101.9° ± 6.3° postoperatively, increasing by 8.6° during stapedotomy (p < 0.01). There were weak and negative correlations between ISJ angle changes and postoperative air conduction gains at frequencies ≤1 kHz and bone conduction gains at 0.5 kHz. When the postoperative ISJ angle changed more than 20°, the success rate of the procedure decreased to 0%. CONCLUSION: The stapedotomy operation increased the ISJ angle. The success of postoperative auditory outcomes had more to do with the ISJ angle change than the value of the angle itself, indicating there is no universal ideal ISJ angle that surgeons should aim for during stapedotomy.
PURPOSE: The aims of this article are: (1) is there an ideal incudostapedial joint (ISJ) angle after stapedotomy? (2) is there any difference between pre- and postoperative ISJ angle? and (3) what is the significance of the ISJ angle in postoperative hearing outcomes? METHODS: Forty six ears from 39 different adult patients (28 women and 11 men; 21 left and 25 right ears) with a mean age of 39 years with clinical otosclerosis who underwent stapedotomy between May 2017 and May 2019 were retrospectively registered, including seven bilateral surgery cases. ISJ angle and intravestibular depth of the stapes prosthesis were measured from multiple planar reconstruction-computed tomography images and the length of the prosthesis was measured during surgery. Relationships between the ISJ angle parameters and postoperative hearing outcomes and parameters of the prosthesis were analyzed. RESULTS: The mean ISJ angle was 93.3° ± 8.8° preoperatively and 101.9° ± 6.3° postoperatively, increasing by 8.6° during stapedotomy (p < 0.01). There were weak and negative correlations between ISJ angle changes and postoperative air conduction gains at frequencies ≤1 kHz and bone conduction gains at 0.5 kHz. When the postoperative ISJ angle changed more than 20°, the success rate of the procedure decreased to 0%. CONCLUSION: The stapedotomy operation increased the ISJ angle. The success of postoperative auditory outcomes had more to do with the ISJ angle change than the value of the angle itself, indicating there is no universal ideal ISJ angle that surgeons should aim for during stapedotomy.