Annulus of Zinn
|Annulus of Zinn|
|Latin||Anulus tendineus communis|
The annulus of Zinn, also known as the annular tendon or common tendinous ring, is a ring of fibrous tissue surrounding the optic nerve at its entrance at the apex of the orbit. It is the common origin of the four rectus muscles (extraocular muscles).
The following structures pass through the tendinous ring (superior to inferior):
- Superior division of the oculomotor nerve (CNIII)
- Nasociliary nerve (branch of ophthalmic nerve)
- Inferior division of the oculomotor nerve (CNIII)
- Abducens nerve (CNVI)
- Optic nerve
Some sources distinguish between these terms more precisely, with the anulus tendineus communis being the parent structure, divided into two parts:
- a lower, the ligament or tendon of Zinn, which gives origin to the Rectus inferior, part of the Rectus internus, and the lower head of origin of the Rectus lateralis.
- an upper, which gives origin to the Rectus superior, the rest of the Rectus medialis, and the upper head of the Rectus lateralis. This upper band is sometimes termed the superior tendon of Lockwood.
- Shi X, Han H, Zhao J, Zhou C (2007). "Microsurgical anatomy of the superior orbital fissure". Clin Anat. 20 (4): 362–6. doi:10.1002/ca.20391. PMID 17080461.
- Ko MK, Kim DS, Ahn YK (1999). "Morphological variations of the peripapillary circle of Zinn-Haller by flat section". Br J Ophthalmol. 83 (7): 862–6. doi:10.1136/bjo.83.7.862. PMC 1723100. PMID 10381675.
- "eMedicine - Orbit Anatomy : Article by Guy J Petruzzelli". Archived from the original on 24 March 2008. Retrieved 2008-03-17.
- synd/3938 at Who Named It?
- J. G. Zinn. Descriptio anatomica oculi humani. Göttingen, B. Abrami Vandenhoeck, 1755.