Chorda tympani nerve course and feasibility of its preservation during atresiaplasty for congenital aural atresia

Laryngoscope Investig Otolaryngol. 2022 Sep 30;7(6):2029-2034. doi: 10.1002/lio2.938. eCollection 2022 Dec.

Abstract

Objectives: The association between the chorda tympani nerve (CTN) and atresiaplasty has not been investigated. This study aimed to describe the course of the CTN observed during atresiaplasty for congenital aural atresia (CAA) and explore the feasibility of CTN preservation.

Methods: In this retrospective study, six consecutive patients who underwent atresiaplasty in a tertiary academic center were included. The course of the tympanic segment of the CTN and its preservation feasibility were evaluated. Atresiaplasty was performed using an anterior approach. The average Jahrsdoerfer score was 8.7 points (range, 8-9 points).

Results: The CTN was located in the atretic plate in all patients. It emerged from an average of 5.6 mm (range, 5.2-6.1) inferior to the incus buttress and crossed the middle ear in an anterior-superior direction. The distance between the neck of the malleus and the CTN varied in the absence of the malleus handle. However, when the malleus handle developed, the CTN passed between the incus and the malleus handle. The CTN was preserved in two of the six patients. They had a Jahrsdoerfer score of 9 and grade I microtia.

Conclusion: The CTN was located in the atretic plate, emerging from an average distance of 5.6 mm inferior to the incus buttress. The incus buttress might serve as a good anatomical landmark to identify and preserve the CTN. CTN preservation is feasible in atresiaplasty candidates with a Jahrsdoerfer score of 9 and auricular deformity of grade I.

Level of evidence: 4.

Keywords: atresiaplasty; chorda tympani nerve; congenital aural atresia; incus buttress; microtia.