IV - Ocular Appendages: Ocular Adnexa Flashcards
What supplies the vasculature of the eyebrows?
Supraorbital and supratrochlear branches of the ophthalmic artery
What veins drain the eyebrows?
Supraorbital and supratrochlear veins - drain anteriorly into the angular vein and into the facial vein
What supplies the temporal innervation of the eyebrows?
Lacrimal nerve
What supplies the central innervation of the eyebrows?
The supraorbital nerve
What supplies the medial innervation of the eyebrows?
Supratrochlear nerve
The lacrimal, supraorbital and supratrochlear nerves are all part of which nerve?
The ophthalmic division of the trigeminal nerve
What is another name for the eyelids?
Palpebrae
The eyelids play an integral role in what?
The distribution of the tear film over the ocular surface
What divides the superior and inferior eyelid?
The superior palpebral sulcus and inferior palpebral sulcus (for upper and lower lid)
In palpebral sulcus divides the eyelid into what two parts?
Orbital
Tarsal
What forms the superior palpebral sulcus ?
The insertion of the fibers of the aponeurosis of the elevator palpebral superiors into the tarsal plate
The tarsal portion of the lid lies closest to what?
The ciliary margin
What is distinctive about eh tissue around the tarsal place?
Thin skin
Lacks fat
What forms the ill-defined inferior palpebral sulcus?
A few connections between the skin and the underlying orbicular oculi muscle
What is the area called where the superior and inferior palpebrum meet laterally and medially?
Lateral canthus
Medial canthus
What is the palpebral issue?
The space between the eyelids
The palpebral issue is the opening to what?
The conjunctival sac
In general, the ciliary margin of the superior palpebrum covers what?
The superior corneoscleral limbus
Where is the ciliary margin of the inferior eyelid seen?
About 1 mm below the inferior limbus
Which canthus lies directly on the globe?
Lateral canthus
How far from the globe is the medial canthus located?
About 6 mm
What makes up the lacus lacrimalis?
Plica smilunaris
Lacrimal caruncle
What is the vertical fold of skin that overlaps the medial angle called?
Epicanthus
What type of edge is found on the lateral 5/6ths of the eyelid?
Squared edge
The ciliary margin of the lacrimal portion of the lid has what type of edge?
Rounded edge
What is found about 5 mm from the medial canthus?
Papilla lacrimalis
What is found at the top of the papilla lacrimalis?
Punctum lacrimalis
Where does the lacrimal punctum drain?
Into the lacrimal canaliculi
About how many eyelashes are found in the upper lid?
150
About how many lashes are found in the lower lid?
75
How often are lashes replaced?
100-150 days
In how many rows are eyelashes on the superior lid arranged?
2-3
What is distichiasis?
An accessory row of lashes arising from meibomian glands
What is trichiasis?
A misdirected lash
Where are the orifices of the meibomian glands found?
Just posterior to the cilia
What to the meibomian glands secrete?
The oily layer of the tear film
What marks the mucocutaneous junction?
The posterior edge of the orifices of the meibomian glands
Where is the gray line seen?
Between the lashes and the orifices of the meibomian glands
What does the gray line represent?
The division between the anterior and posterior portion of the eyelid
What nerve provides the sensory innervation for the lateral superior lid?
Lacrimal
What nerve provides the sensory innervation for the middle of the superior lid?
Supraorbital
What nerve provides the sensory innervation for the medial superior lid?
Supratrochlear
The three branches that supply innervation to the superior lid stem from which nerve?
Ophthalmic division of the trigeminal nerve
What provides the sensory innervation for the lateral inferior lid?
Infraorbital
What provides the sensory innervation for the medial inferior lid?
Infratrochlear
Which larger nerve branch does the infraorbital nerve belong to?
Maxillary division of the trigeminal
Which larger nerve branch does the infratrochlear nerve belong to?
Nasociliary nerve - part of the ophthalmic division of the trigeminal
What are the two main arteries that supply the eyelids?
Lacrimal
Ophthalmic
The lacrimal artery branches into which arteries?
Superior and inferior lateral palpebral artery
The ophthalmic artery gives rise to which arteries?
Superior and inferior medial palpebral arteries
What veins form the drainage of the medial portion of the eyelids?
Angular and ophthalmic veins
What vein drains the lateral portion of the eyelids?
Superficial temporal vein
What are the four portions of the orbicularis oculi?
Orbital
Palpebral
Lacrimal
Ciliary
The orbital portion of the orbicularis oculi encircle what other portion of the muscle?
Palpebral portion
What is another name for the ciliary portion of the orbicularis oculi?
Muscle of Riolan
What is the function of the ciliary portion of the orbicularis oculi?
To keep the ciliary margin of the eyelid opposed to the globe
What is the action of the orbital portion of the orbicularis oculi?
Pursestring - drawing the lids toward the medial cants and closing the fissure
What is the antagonist to the orbital portion of the orbicularis oculi?
Frontalis
What is the function of the palpebral portion of the orbicularis oculi?
Depresses upper lid
Slightly raises lower lid
What is the antagonist to the palpebral portion of the orbicularis oculi?
Levator palpebrae superioris
What is the function of the lacrimal portion of the orbicularis oculi?
Pulls eyelids medially
Pulls on lacrimal fascia to dilate the the lacrimal sac
What provides the innervation to the orbicularis oculi?
CN VII - Facial nerve
The elevator palpebrae superioris muscle sheath blends with with other muscle?
Superior rectus
As the fibers of the levator enter the upper lid, the aponeurosis penetrates what?
Orbital septum
As a few of the fibers of the levator aponeurosis pass between the fibers of the orbicularis oculi and insert into the skin, they create what structure?
Superior palpebral sulcus
What provides the innervation of the levator?
CN III - oculomotor
What is another name for the superior tarsal muscle?
Muscle of Muller
What is the function of the superior tarsal muscle?
Helps keep the lid up once the levator las lifted it
What is the neural innervation of the superior tarsal muscle?
Postganglionic sympathetic fibers from the sympathetic plexus arising from the superior cervical ganglion
What are the glands of Zeiss?
Modified sebaceous glands - keep the cilia lubricated
What are the glands of Moll?
Modified sweat glands - secrete into hair follicle or ciliary margin of the lid