Adnexa Of The Eye Flashcards
Which Greek and Latin words mean eyelid?
Palpebral
Blepharo
Which gland is found in the eyelid, to keep eyelashes healthy?
Sebaceous gland
What is the name of the gland that produces waxes to line the upper and lower eyelids? Why does it do this?
Tarsal gland
Stop tears flowing constantly
What is the palpebral fissure?
Space between two eyelids when eye is open
Not presence when eyes shut
What is the name of the 3rd eyelid?
Nicitating membrane
What are the 3 layers found in the eyelid?
Skin
Musculofibrous
Palpebral conjuctiva
What is found in the musculofibrous layer of the eyelid?
Glands
Smooth and somite muscle
Connective tissue
Pharyngeal arch muscle
What is a sty?
An infection of the sebaceous gland
Which muscle closes the eye? What is it’s innervation?
Obicularis oculi
Palpebral branch of auricopalpebral nerve
Which muscle lifts the upper eye and brow? Which nerve innervates this?
Superciliaris
Palpebral branch of auriculopalpebral nerve
Which muscle draws the lateral palpebral angle posteriorly? Which muscle innervates this?
Retractor anguli oculi
Palpebral branch of auriculopalpebral nerve
Which muscle lifts the upper eyelid? Where is it found? What is it innervates by?
Levator palpebral superioris
Inside the bony orbit of the eye
Occulomotor nerve
What innervates the smooth muscle found in the eyelids?
Sympathetic NS - afferent efferent
Cranial cervical ganglion
The sensory nerve supply to the eye is from the trigeminal branches. Which branches supply the upper and lower eyelid?
Upper - ophthalmic division of maxillary
Lower - maxillary
What can entropion lead to?
Conjuctivitis and corneal ulcers
What is ectropion?
The drooping of an eyelid (usually bottom), exposing the palpebral conjuctiva
Leads to epiphora and conjuctivits
What is epiphora?
Excess tear production
The palpebral conjuctiva continues across the front surface of the cornea, where it is referred to as…
Bulbar conjunctiva
How can deep ulcers be healed?
Stitch conjuctiva over ulcer, provide blood supply, then remove conjuctiva
What is the lacrimal apparatus?
Structures which create lacrimal fluid Lacrimal gland (above lateral canthus of upper palpebral) other glands, gland of 3rd eyelid
What type of gland is the lacrimal gland? What is its nerve supply?
Serous and mucous
Autonomic efferent
Where is the nasolacrimal duct found? What is it’s purpose?
Within the maxilla, above upper canines
Tears drain from lacrimal duct to nasal cavity
Nasolacrimal duct occlusion are common in rabbits. Why is this?
Uncared for rabbits teeth grow up into socket
Above the tooth socket is the nasolacrimal duct
What is the nicitating structure? What can be an issue with this strucure?
T shaped cartilage and fold in medial canthus of eye
Prolapse
Why does the nicitating membrane slide over the eyeball when blinking?
Eyeball is retracted by retractor bulbs muscle
3rd eyelid slips over the gap
What is the periorbital fascia?
Fibrous tunic, cone shaped surrounding eye and extra ocular muscles
What are the 3 layers of the periorbital fascia?
Deep muscular fascia
Superficial muscular fascia
Periorbita
How many extraoccular muscles are there? What are the 3 groups?
7
4 rectus
2 oblique
1 retractor
What are the 4 rectus extraoccular muscles? Where do they insert? What is their innervation?
Dorsal, ventral, medial lateral rectus
Move pupil
Rostrally to the equator
Occulomotor nerve
What are the 2 oblique extraocular muscles? WHere do they insert? What is their action? What is it’s innervation?
Dorsal and ventral
Insert rostrally to the equator
Dorsal - moves the dorsal eyeball medially and centrally. Ventral - moves ventral eyeball medially and dorsally
Trochlear nerve
What is the 1 retractor extraoccular muscle and where does it originate from? It is partially innervated by which nerve?
Retractor bulbi
Optic canal and orbital fissure
Abducent
