OPT 114: Orbit-Foramina, Fissures, and Fossas

foramen

hole or opening in bone; allows entrance and exit of nerves and vessels in and out of the orbit

4 types of foramen

Optic foramen (canal), supraorbital foramen, supratrochlear foramen, infraorbital foramen

fissure

long, narrow opening in bone; allow entrance and exit of nerves and vessels in and out of the orbit

2 types of fissure

Superior orbital fissure and inferior orbital fissure

fossa

shallow depression in bone

optic foramen (optic canal)

lies between the lesser wing and body of the sphenoid; at the orbital apex; opening between orbit and cranial cavity; common tendinous ring (annulus of Zinn) lies anterior; cranial nerve II and the ophthalmic artery pass through optic canal

Common tendinous ring (Annulus of Zinn)

origin for 4 of the extraocular muscles; band of connective tissue

another name for optic foramen

optic canal

the optic foramen is located at the orbital ______

apex

____________ and ____________ pass through the optic canal/foramen and annulus of Zinn

cranial nerve II and ophthalmic artery

Optic canal/foramen

What's "1"?

common tendinous ring

What's "2"?

superior orbital fissure

lies between the greater and lesser wings of sphenoid; inferior portion at the orbital apex; slightly nasal, posterior portion of orbit; opening between orbit and cranial cavity

The common tendinous ring (annulus of zinn) lies anterior to the _____________ portion of the superior orbital fissure

inferior

nerves that pass through the superior orbital fissure and annulus of zinn

superior and inferior division of oculomotor nerve (CN III), nasociliary nerve (CN V-1), abducens nerve (CN VI)

nerves and vessels that pass through the superior orbital fissure and ABOVE the annulus of zinn

superior ophthalmic vein, trochlear nerve (CN IV), lacrimal nerve (CN V-1), frontal nerve (CN V-1)

cranial nerve III

oculomotor nerve

cranial nerve VI

abducens nerve

cranial nerve IV

trochlear nerve

cranial nerve V-1

opthalmic

cranial nerve V-2

maxillary

cranial nerve V-3

mandibular

cranial nerve V

trigeminal

inferior orbital fissure (infraorbital fissure)

lies between the floor of the orbit and the lateral wall; opening between orbit and cranial cavity

inferior orbital fissure

What's "4"?

nerves and vessels that pass through the inferior orbital fissure

inferior ophthalmic vein, zygomatic nerve, infraorbital nerve, artery, and vein

the inferior orbital fissure continues along the infraorbital __________ to pass through the infraorbital ______ and infraorbital ____________.

groove; canal; foramen

lacrimal fossa (for the lacrimal gland)

located in frontal bone temporally; sits in the fossa

lacrimal gland

What is "5"?

lacrimal sac

What is "6"?

lacrimal fossa (for the lacrimal sac)

located medially; formed by lacrimal bone and frontal process of the maxillary bone; where lacrimal sac sits; separated from orbit by orbital septum

Ridge in lacrimal bone forms _____________ lacrimal crest

posterior

Ridge in maxillary bone forms _____________ lacrimal crest

anterior

nasolacrimal canal

a canal in the maxillary bone extends from the fossa to open into the nasal cavity

nasolacrimal duct

located in the nasolacrimal canal

lacrimal bone; nasolacrimal canal

What's "1" and "2", respectfully?

lacrimal fossa; anterior lacrimal crests; posterior lacrimal crests

What's "1", "2", and "3", respectfully?

synonym for foramen

notch

superior orbital (supraorbital) foramen/notch

located in frontal bone medially; opening between orbit and facial surface

What passes through the superior orbital foramen/notch?

supraorbital nerve (CN V1), artery, and vein

superior trochlear (supratrochlear) foramen/notch

located in the frontal bone medial to the supraorbital foramen; opening between the orbit and facial surface

what passes through the superior trochlear foramen/notch?

supratrochlear nerve (CN V1), artery, and vein

Picture of supraorbital and supratrochlear foramen/notch

inferior orbital (infraorbital) foramen

located in the maxillary bone; opening between the orbit and facial surface

movement of infraorbital nerve (CN V2), artery, and vein

inferior orbital fissure --> infraorbital groove --> infraorbital canal --> infraorbital foramen

infraorbital foramen

What's "1"?

What type of cranial nerve is nasociliary nerve?

V1

What type of cranial nerve is lacrimal nerve?

V1

What type of cranial nerve is the frontal nerve?

V1

What type of cranial nerve is the zygomatic nerve?

V2

What type of cranial nerve is the infraorbital nerve?

V2

What type of cranial nerve is the supraorbital and supratrochlear nerve?

V1