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Published on: February 29, 2020
Bony sheathed chorda tympani: a unique case of incudomalleolar fixation
Omer Afsin Ozmen1, Sarp Sarac, Levent Sennaroglu
1Department of Otolaryngology Head and Neck Surgery, Hacettepe University Faculty of Medicine, Yenisehir, Ankara, Turkey. oaozmen@yahoo.com
Objective:
To describe a unilateral conductive hearing loss caused by restriction of the movements of malleus and incus due to chorda tympani in a bony sheath.
Patient:
A 23-year-old man with a stable mild conductive hearing loss in the left ear and mild sensorineural hearing loss in the right ear.
Intervention:
An exploratory tympanotomy was performed.
Main Outcome Measure:
Immobility of the ossicles due to a bony structure, which was found to be chorda tympani encircled in a bony sheath. Ossicular system regained its mobility with the severance of the chorda tympani.
Results:
Hearing was improved both subjectively and audiographically.
Conclusion:
This is the second case of chorda tympani with a bony sheath and the first case of this pathologic finding affecting both malleus and incus. Bony sheathed chorda tympani is considered to be a congenital anomaly of the chorda tympani that causes incudomalleolar fixation and behaves as posterior bony bars.
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