Impact of Fenestration Size and Prosthesis Diameter on Hearing Outcomes After Stapedotomy: A Review

This systematic review investigates the influence of fenestration size and prosthesis diameter on hearing outcomes in patients undergoing primary stapedotomy for otosclerosis. A total of 11 studies were included, comprising randomized controlled trials, cohort studies, and one cross-sectional study, with follow-up durations ranging from three months to one year. Fenestration sizes most commonly ranged from 0.5 mm to 0.8 mm, while prosthesis diameters varied between 0.4 mm and 0.6 mm. Across studies, postoperative air conduction thresholds improved by 20-30 dB, and air-bone gap (ABG) closure within 10 dB was achieved in 57% to 88.9% of cases. Although some studies reported marginally better bone conduction gains with 0.6 mm prostheses, no definitive audiological superiority was established for any specific fenestration-prosthesis size combination. The use of larger prosthesis diameters was associated with modest improvements in mid-frequency sound transmission, particularly at 2000 Hz, but these differences were often not statistically significant. Postoperative complications were minimal, with transient vertigo being the most commonly reported, especially in laser-assisted techniques. Importantly, no study linked complication rates directly to specific fenestration or prosthesis sizes. Overall, the findings suggest that both fenestration size and prosthesis diameter within the commonly used ranges yield consistently favorable audiological outcomes without significantly affecting safety. The choice of prosthesis size may be tailored to individual anatomical and surgical considerations without compromising efficacy. This review highlights the flexibility in surgical approach for stapedotomy, supporting the use of varying size parameters according to intraoperative conditions and surgeon preference.