Tympanic annulus
Last revised by Kajanan Nithiyananthan
on 25 Mar 2025
Citation, DOI, disclosures and article data
Citation:
Bell D, Nithiyananthan K, Weerakkody Y, Tympanic annulus. Reference article, Radiopaedia.org (Accessed on 27 Mar 2025) https://doi.org/10.53347/rID-57541
rID:
57541
Article created:
Disclosures:
At the time the article was created Daniel J Bell had no recorded disclosures.
View Daniel J Bell's current disclosures
Last revised:
25 Mar 2025,
Kajanan Nithiyananthan
Disclosures:
At the time the article was last revised Kajanan Nithiyananthan had no financial relationships to ineligible companies to disclose.
View Kajanan Nithiyananthan's current disclosures
Revisions:
5 times, by
3 contributors -
see full revision history and disclosures
Systems:
Sections:
Synonyms:
- Annulus of the tympanic membrane
The tympanic annulus, also known as the tympanic ring, is the thickened edge of the pars tensa of the tympanic membrane, anchoring it in the tympanic sulcus 3.
Gross anatomy
The tympanic annulus is formed by a fibrocartilaginous thickening of the edge of the pars tensa and has a horseshoe-shaped configuration. It is deficient superiorly at the notch of Rivinus, where the pars flaccida is found 1. The tympanic annulus inserts into the tympanic sulcus, a shallow groove of the external acoustic canal (EAC), attaching the tympanic membrane to the EAC. The annulus has a triangular cross-section with the base inserted into the sulcus and the apex pointing towards the tympanic membrane 3.
History and etymology
The notch of Rivinus was first described by Augustus Quirinus Rivinus (1652–1723), a German anatomist 2.
References
- 1. Kassem F, Ophir D, Bernheim J, Berger G. Morphology of the human tympanic membrane annulus. (2010) Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery. 142 (5): 682-7. doi:10.1016/j.otohns.2010.01.020 - Pubmed
- 2. Mosby. Mosby's Medical Dictionary. ISBN: 9780323414258
- 3. Salah Mansour, Jacques Magnan, Hassan Haidar, Karen Nicolas, Stéphane Louryan. Comprehensive and Clinical Anatomy of the Middle Ear. ISBN: 9783642369674
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