(889) The Effect of Stapes Piston Diameter Size: A Systematic Review and Meta-Analysis

Introduction: Stapedotomy is considered the gold standard for surgical management of otosclerosis. Variability exists in the use of piston diameter size. The aim of this systematic review and meta-analysis is to evaluate hearing and complication outcomes for various stapes piston diameter sizes following stapedotomy procedures.

Methods: A database search was conducted in October 2024 using MEDLINE, Embase, and Web of Science. Retrieved studies underwent abstract and full-text screening. Studies were included with extractable post-operative hearing and complication outcomes, and categorized by piston diameter size (0.4, 0.5, 0.6 mm). Meta-analyses and two sample proportion tests were completed using RevMan and Stata 19.

Results: The full text review yielded 126 stapedotomy interventions. Meta-analyses using a random effects model demonstrated no significant post-operative difference in # of patients with air-bone-gap (ABG) < 10dB (p= 0.72) or new sensorineural hearing loss (p= 0.32) between 0.4 and 0.6mm piston diameters. A single arm meta-analysis evaluating post-operative ABG pooled means for 0.4, 0.5, and 0.6mm piston size were 7.85 dB HL (6.42 - 9.29, 95% CI), 8.78 dB HL (6.78 - 10.78, 95% CI), and 9.74 dB HL (8.15 - 11.33, 95% CI), respectively. A significant difference was noted in overall events of new post-operative dizziness favoring 0.4mm stapes piston compared to both 0.5mm (p= 0.001) and 0.6mm (p= 0.001) diameters.

Conclusions: No significant difference in hearing outcomes were observed as a function of piston diameter. A difference in post-operative dizziness rates may be associated with larger piston diameters and requires further investigation.