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Article contents
Difficult round window access during cochlear implantation: a simple prediction method utilising pre-operative CT imaging
Published online by Cambridge University Press: 05 December 2025
Abstract
Objective
Difficulty visualising the round window is occasionally encountered during cochlear implant surgery. This paper presents a novel method for predicting difficult round window accessibility using pre-operative computed tomography (CT) imaging.
Methods
This is a retrospective multicentre study of all cochlear implantation surgical procedures conducted in two Singaporean tertiary hospitals between 2018 and 2021. Pre-operative CT temporal bone scans were reviewed and two lines were drawn on a single axial cut. Where both lines intersect medially, difficult round window visualisation is predicted. Computed tomography predictions were compared with intra-operative findings, and statistical analysis was performed.
Results
In 9 of 89 cases (10.1 per cent) difficult round window access was noted intra-operatively and 8 cases (88.9 per cent) were correctly predicted by the novel method (p < 0.001; sensitivity, 89 per cent; specificity, 100 per cent).
Conclusion
This study describes a simple, effective method to predict difficult round window access on axial CT temporal bone images, without reconstructed images or complex calculations.
Information
- Type
- Main Article
- Information
- Copyright
- © The Author(s), 2026. Published by Cambridge University Press on behalf of J.L.O. (1984) LIMITED.
Footnotes
Ng Jia Hui takes responsibility for the integrity of the content of the paperPresented at the 14th Asia Pacific Symposium of Cochlear Implant and Related Sciences, November 2023, Seoul, South Korea, and the 17th International Conference on Cochlear Implants and other Implantable Technologies, July 2024, Vancouver, Canada. Poster presentation was 9th to 11th November 2023 in Seoul, South Korea and Oral presentation was 11th July 2024 at Vancouver, Canada.
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