Tenon's capsule

Tenon's capsule
The right eye in sagittal section, showing Tenon's capsule (semidiagrammatic).
Details
Location	Orbit (anatomy)
Identifiers
Latin	vagina bulbi, capsula Tenoni
MeSH	D058475
Anatomical terminology [edit on Wikidata]

Tenon's capsule (/təˈnoʊn/), also known as the Tenon capsule, fascial sheath of the eyeball (Latin: vagina bulbi) or the fascia bulbi, is a thin membrane which envelops the eyeball from the optic nerve to the corneal limbus, separating it from the orbital fat and forming a socket in which it moves.

The inner surface of Tenon's capsule is smooth and is separated from the outer surface of the sclera by the periscleral lymph space. This lymph space is continuous with the subdural and subarachnoid cavities and is traversed by delicate bands of connective tissue which extend between the capsule and the sclera.

The capsule is perforated behind by the ciliary vessels and nerves and fuses with the sheath of the optic nerve and with the sclera around the entrance of the optic nerve. In front it adheres to the conjunctiva, and both structures are attached to the ciliary region of the eyeball.

The structure was named after Jacques-René Tenon (1724–1816),^[1] a French surgeon and pathologist.