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DOI: 10.1055/s-0044-1787287
Medical Illustration - A Pictorial Essay Visual Illustration of Obstetric Anal Sphincter Injuries (OASIS) Degrees of Severity, a Picture is Worth a Thousand Words
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Abstract
Obstetric anal sphincter injury affects about 5.7% of primiparous women who deliver vaginally. Perineal injury during childbirth is a common event with important morbidity associated with third-and-fourth degree perineal tears (also referred to as obstetric anal sphincter injuries—OASIS). As there was a lack of consistency in the classification of a partial anal sphincter injury, with up to 33% of consultant obstetricians classifying a complete or partial tear of the EAS as a second-degree tear. We have proposed simple, digital diagrammatic drawings to visually represent all degrees (grades) of OASIS based on the WHO OASIS classification.
Keywords
obstetric anal sphincter injuries (OASIS) - anal sphincter - perineal tear - faecal incontinence - diagnostics - treatmentDeclaration of Interest Statement
There are no relevant financial or non-financial competing interests to report.
Abbreviations
OASIS: obstetric anal sphincter injuries, AI: anal incontinence, EAS: external anal sphincter, IAS: internal anal sphincter, RTC: randomized control trial. SVD: spontaneous vaginal delivery, WHO: World Health Organization.
Publication History
Received: 11 January 2024
Accepted: 09 April 2024
Article published online:
06 June 2024
© 2024. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution 4.0 International License, permitting copying and reproduction so long as the original work is given appropriate credit (https://creativecommons.org/licenses/by/4.0/)
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