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Endoscopic classification system of pars tensa retractions
Nilesh Mahajan1, Vinay Kumar Vijayendra1, Miriam Redleaf2
1Vijaya ENT Care Centre, Superspeciality Otology Centre, Bangalore, India.
Background:
Previous classification systems of pars tensa retractions have not consistently incorporated ossicular erosion or the presence of cholesteatoma.
Objective:
This study aimed to illustrate our classification of pars tensa retractions, which is more precise than previous systems, with aided use of the endoscope.
Methods:
A retrospective study was carried out on 200 ears of 170 patients whose pars tensa retractions had been documented at a tertiary otological referral centre.
Results:
A classification system was developed. Pars tensa retractions were divided into the following subcategories: grade 0, grade 1, grade 2a, grade 2b, grade 3a, grade 3b, grade 3c, grade 4a, grade 4b, grade 4c, grade 5a, grade 5b and grade 5c.
Conclusion:
This classification system was able to accommodate all pars tensa retractions. The distribution of grades of pars tensa retractions was based on ossicular status and the presence or absence of cholesteatoma. It is therefore a more applicable, and functionally based system than previous alternatives.
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