Orbit Anatomy Flashcards
The orbit is a ______ shaped space with the ____ sited posteriorly and the _____ anteriorly. It is made up of __ bones.
Pyramidal shaped
Apex posterior
Base anterior
7 bones
List the 7 bones which make up the orbit
Frontal Zygomatic Sphenoid Maxillary Palatine Lacrimal Ethmoidal
Where is the optic foramen located?
The lesser wing of the sphenoid
What is carried in the optic foramen?
The optic nerve and the ophthalmic artery
Where is the superior orbital fissure?
This is located between the greater and lesser wing of the sphenoid
What is the orbital septum and where is it located?
This is a thin membranous layer which forms the fibrous part of the eyelids.
Located anterior to the orbit and extends from the orbit to the eyelid.
The superior orbital fissure is divided into the superior and inferior parts. What is carried in each?
Superior: Superior ophthalmic vein, lacrimal nerve, frontal nerve and the CNIV
Inferior: CNIII, nasociliary nerve and CNVI
Where is the inferior orbital fissure located? What does it carry?
Between the maxiall and the greater wing of the sphenoid.
Contains: infraorbital nerve, zygomatic nerve and inferior ophthalmic vein.
The infraorbital an zygomatic nerves are branches of what?
CNV2
What is the common tendinous ring (a.k.a annulus of Zinn)?
This is a fibrous tissue surrounding the optic canal and inferior part of the SOF, which marks the origin of the four recti muscles.
What runs through the common tendinous ring?
CNII
CNIII
CNVI
Nasociliary nerve
What is significant about retrobulbar anaesthesia?
This will block all the nerves inside the common tendinous ring
