Common tendinous ring | |
---|---|
![]() Rectus muscles: 2 = superior, 3 = inferior, 4 = medial, 5 = lateral Oblique muscles: 6 = superior, 8 = inferior Other muscle: 9 = levator palpebrae superioris Other structures: 1 = Common tendinous ring, 7 = Trochlea, 10 = Superior tarsus, 11 = Sclera, 12 = Optic nerve | |
![]() Anterior view | |
Details | |
Identifiers | |
Latin | anulus tendineus communis |
TA98 | A15.2.07.015 |
TA2 | 2047 |
FMA | 49071 |
Anatomical terminology |
The common tendinous ring, also known as the annulus of Zinn or annular tendon, 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 recti muscles of the group of extraocular muscles.
It can be used to divide the regions of the superior orbital fissure.[1]
The arteries surrounding the optic nerve form a vascular structure known as the circle of Zinn-Haller, or sometimes as the circle of Zinn.[2]
The following structures pass through the tendinous ring (superior to inferior):