Anatom3DCommon tendinous ring
Anulus tendineus communis · Společný šlachový prstenec
Fascia & connective tissue
Looks like
A ring of tough tendon at the back of the eye socket, surrounding the opening where the optic nerve enters.
What it does
Anchors the four straight eye muscles and lets the optic nerve and several eye nerves pass through it.
Keeping it well
Swelling of the optic nerve here makes eye movement painful with blurred vision (optic neuritis); see a doctor the same day.