What is the function of the common tendinous ring?
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 rectus muscles of the group of extraocular muscles . It can be used to divide the regions of the superior orbital fissure.
What is the tendinous ring of Zinn?
The tendinous ring, also known as the annulus of Zinn, is the common origin of the four rectus muscles ( extraocular muscles ). The tendinous ring straddles the lower, medial part of the superior orbital fissure. It attaches to a tubercle on the greater wing of the sphenoid bone (at the margin of the superior orbital fissure).
What is the tendinous ring of the eye?
The tendinous ring, also known as the annulus of Zinn, is the common origin of the four rectus muscles ( extraocular muscles ). The tendinous ring straddles the lower, medial part of the superior orbital fissure.
What is the tendinous ring of the rectus?
Dr Candace Makeda Moore and A.Prof Frank Gaillard ◉ ◈ et al. The tendinous ring, also known as the annulus of Zinn, is the common origin of the four rectus muscles (extraocular muscles). The tendinous ring straddles the superior orbital fissure and through it (from superior to inferior) pass:
Which structures passes by common tendinous ring?
The tendinous ring straddles the lower, medial part of the superior orbital fissure....Through it (from superior to inferior) pass:superior division of the oculomotor nerve (CN III)nasociliary nerve (a branch of the ophthalmic nerve)inferior division of the oculomotor nerve (CN III)abducens nerve (CN VI)
What muscles attach to common tendinous ring?
The ring blends with the dural sheath of the optic nerve, medially. The common tendinous ring provides attachment for all four rectus muscles.
Does optic nerve go through common tendinous ring?
Several neurovascular structures pass through the common tendinous origin. After passing through the optic canal and exiting via the optic foramen, the optic nerve and ophthalmic artery traverse through the common tendinous origin to enter the orbital apex.
Which muscle passes through the tendinous ring of the orbit?
the Rectus MusclesOrigin of the Rectus Muscles The four rectus muscles have their origin on the common tendinous ring (annulus of Zinn). This oval band of connective tissue is continuous with the periorbita and is located at the apex of the orbit anterior to the optic foramen and the medial part of the superior orbital fissure.
Which of the following structures does not travel through the common tendinous ring?
Correct Answer: Ophthalmic artery.
What artery passes through optic canal?
the ophthalmic arteryThe optic canal is a very important structure due to the structures that pass through this canal, mainly the optic nerve and the ophthalmic artery.
Which extraocular eye muscle does not originate at the common tendinous ring?
The superior obliqueThe superior oblique is one of the two noteworthy oblique extraocular muscles. These muscles are unique in that they do not originate from the common tendinous ring, have an angular attachment to the eyeball, and they attach to the posterior aspect of the eyeball.
What goes through Zinn annulus?
The optic, oculomotor, and abducens nerves all pass through the annulus of Zinn, while the trochlear nerve travels just medial to the annulus of Zinn. The nasociliary nerve is the sole portion of the ophthalmic division of cranial nerve V which passes through the annulus of Zinn.
What is circle of Zinn Haller?
The circle of Zinn–Haller (CZH) is known to be an intrascleral arteriolar anastomosis derived from medial and lateral paraoptic short posterior ciliary arteries (SPCAs). The significance of this arterial circle in supplying the anterior optic nerve and peripapillary region has been the subject of controversy.
What is the common origin of the four rectus muscles called?
The annulus of Zinn is the common origin point for the rectus muscles and spans the superior orbital fissure and orbital apex. It consists of superior and inferior tendons. The superior tendon is involved with the entire superior rectus muscle as well as portions of the medial rectus and lateral rectus muscles.
What are the muscles that move the eye called?
There are six extraocular muscles that move the globe (eyeball). These muscles are named the superior rectus, inferior rectus, lateral rectus, medial rectus, superior oblique, and inferior oblique.
What nerves go through common tendinous ring?
Through it (from superior to inferior) pass: superior division of the oculomotor nerve (CN III) nasociliary nerve (a branch of the ophthalmic nerve) inferior division of the oculomotor nerve (CN III)
What Innervates nasociliary nerve?
The nasociliary nerve contributes to the innervation of the iris, ciliary body, cornea, conjunctiva of the upper eyelid, root of the nose, lacrimal sac, caruncle, mucous membrane of the anterior part of the nasal septum, nasal wall, middle and inferior turbinate bones, and the cartilaginous tip of the nose.
Which of the following muscles is not innervated by the oculomotor nerve?
The oculomotor nerve innervates all the extraocular muscles except the superior oblique (trochlear nerve) and lateral rectus (abducens nerve).
What is the medial portion of the ring?
The medial portion of the ring also encompasses the optic foramen through which the optic nerve and ophthalmic artery pass. A memory aid for the specific nerves in the structure is the mnemonic for the contents of the annulus of Zinn.
What is the annulus of Zinn?
Tendinous ring. The tendinous ring, also known as the annulus of Zinn, is the common origin of the four rectus muscles ( extrao cular muscles ). The tendinous ring straddles the lower, medial part of the superior orbital fissure. It attaches to a tubercle on the greater wing of the sphenoid bone (at the margin of the superior orbital fissure).
Which part of the ring encompasses the optic nerve?
The medial portion of the ring also encompasses the optic foramen through which the optic nerve and ophthalmic artery pass.
Which portion of the ring encompasses the optic foramen through which the optic nerve and ophthalmic?
Through it (from superior to inferior) pass: The medial portion of the ring also encompasses the optic foramen through which the optic nerve and ophthalmic artery pass. A memory aid for the specific nerves in the structure is the mnemonic for the contents of the annulus of Zinn.
What is the annulus of the eye?
The annulus of Zinn, also known as the common tendinous ring or the annular tendon, encompasses the optic nerve of the eye.
What are the three nerves that connect the rectus muscles?
The three nerves are: the nasocilliary nerve, which branches from the optic nerve, the abducens or sixth cranial nerve, and the oculomotor or third cranial nerve. The one artery that passes through the ring, the opthalmic artery, supplies the eye with the necessary blood supply.
