Periorbita

Periorbita is the fibrous membrane that lines the orbit and encloses the eye and its associated structures. It is also known as the orbital fascia or the orbital periosteum. The periorbita is a dense, fibrous membrane that is continuous with the dura mater, the outermost layer of the meninges that surround the brain and spinal cord.

Anatomy[edit | edit source]

The periorbita lines the inside of the bony orbit, a cone-shaped cavity in the skull in which the eye and its appendages are situated. It is closely adherent to the bone and cannot be separated from it. The periorbita is continuous with the dura mater at the optic canal and the superior orbital fissure, openings in the back of the orbit that allow structures such as the optic nerve and ocular muscles to pass through.

Function[edit | edit source]

The periorbita serves to protect the eye and its associated structures from injury. It provides a barrier against the spread of infection from the sinuses and the face to the orbit. The periorbita also plays a role in the spread of intraocular pressure, which is important in conditions such as glaucoma.

Clinical significance[edit | edit source]

Damage to the periorbita can occur due to trauma, infection, or surgery. This can result in conditions such as orbital cellulitis, a serious infection of the tissues surrounding the eye, or orbital blowout fracture, a fracture of the bones of the orbit caused by blunt trauma. Treatment of these conditions may involve antibiotics, surgery, or other interventions.

File:Gray's Anatomy plate 848.png

The bony orbit and periorbita. The periorbita is the dense, white tissue lining the inside of the orbit.