How many bones make up the orbit of the eye?
Which bones make up the orbit of the eye?
Which aspect of the frontal bone allows passage of the supraorbital nerve?
Which bone contains the optic canal?
The optic canal is the _____ of the bony orbit
The optic canal is the apex of the bony orbit
What is the main function of the optic rim?
Protects the eye from direct trauma
Which bones mainly comprise the following regions of the bony orbit?
b) Medial wall
c) Lateral wall
a) Roof - Frontal bone
b) Medial wall - Ethmoid bone
c) Lateral wall - Sphenoid bone
d) Floor - Maxilla
Which aspects of the bony orbit are particuarly weak and thin?
- Medial wall (ethmoid)
- Orbital floor (maxilla)
Which type of fractures are the medial wall and floor of the orbit particuarly susceptible to?
Which main problems arise with an orbital blowout fracture?
- Trapped orbital contents
- Infraorbital NVB damage
- Sensory deficit of facial skin
Which areas does the infraorbital nerve innervate?
- Ala of nose
- Skin around maxilla (lower eyelid to upper lip)
Why may a fractured zygoma result in double vision?
- Fractured zygoma rotates medially
- Suspensory ligament attaches to zygoma laterally
- Eye lowered to orbital floor as tension reduced
- Diplopia occurs
What is the name given to the muscle surrounding the orbit of the eye?
The orbicularis oculi is split into which two parts?
- Orbital part
- Palpebral part
Which type of secretion do the tarsal (eyelid) glands secrete?
What is the orbital septum and what is its function?
Sheet of fascia
Aids in preventing spread of infection
What is the name of the muscle(s) which elevates the upper eyelid?
- Levator palpebrae superioris
- Superior tarsal (Müller's*) muscle
*Do not confuse with orbitalis muscle (also known as Müller's muscle)
Which muscle is primarily responsible for:
a) Gently closing eyes
b) Screwing up eyes
a) Orbicularis oculi (palpebral aspect) - Gently closing eyes
b) Orbicularis oculi (orbital aspect) - Screwing up eyes
Which cranial nerve innervates the orbicularis oculi?
Which structure covers the iris?
What is the limbus?
Which glands are responsbile for tear production?
Where does lacrimal fluid drain within the eye?
Puncta (inferior and superior)
What is the conjunctival fornix?
Loose arching folds connecting the conjunctival membrane lining the inside of the eyelid with the conjunctival membrane covering the eyeball
The conjunctiva does not cover which part of the eye?
What is the pathway of lacrimal fluid drainage?
- Lacrimal puncta
- Lacrimal sac
- Nasolacrimal duct
- Nasal cavity
What is the approximate diameter of the eye?
What are the 3 main layers of the eye?
- Fbrous layer
- Vascular layer (uvea)
- Inner layer (retina)
The fibrous layer of the eye is comprised of which two main components?
The vascular layer (uvea) of the eye is comprised of which 3 parts?