Orbital septum

Last revised by Craig Hacking on 27 Mar 2024

The orbital septum (plural: orbital septa) is a thin sheet of fibrous tissue that originates from the orbital rim periosteum and blends with the tendon of the levator palpebrae superioris superiorly and inserts into the tarsal plate inferiorly.

The orbital septum separates the intra-orbital fat from eyelid fat and orbicularis oculi muscle, and also provides a barrier against spread of infection between the preseptal space to postseptal space (orbit proper) 1.

Radiographic appearance


The orbital septum is difficult to identify but appears in the region that contains the separation of the orbital fat from the subcutaneous (eyelid) fat and the orbicularis oculi muscle and together with the eye lids and conjunctiva forms an anterior soft tissue density 2


High-resolution T1WI is a superior imaging technique to depict the orbital septum and hence determine boundaries between the preseptal and postseptal spaces which have important implications in treatment of periorbital infections or anatomic staging of tumors. 

See also

ADVERTISEMENT: Supporters see fewer/no ads