The Eye Flashcards
Describe the pupil
Where light enters the eye to get to the retina at the back
What is the function of the iris?
Is a diaphragm that regulated the size of the pupil to regulate the amount of light that goes into the eye
What is the lacrimal caruncle?
The small, pink, globular tissue found at the inner corner of the eye. It is made of skin covering sebaceous and sweat glands
What is the other name for tear ducts?
Lacrimal punctrum
What is the function of eyelashes?
- Help stop the eyelids from sticking together
- Help stop foreign particles from entering the eye
What is a stye?
Infection of the hair follicles that the eyelashes arise from
What is a clinical sign of thyroid problems (especially hyperthyroidism) with reference to the eye?
Normally can’t see the top of the iris. If can see white all around the iris then is a sign of thyroid problem as patient is likely to have excess fat around the orbit causing the eye to be pushed forwards.
What are Meibomian glands and what do they do?
Glands found further bac on eyelid that produce an oily secretion.
This secretion stops the tears spilling onto the face
Why do we have tears?
To keep the eye moist
Meibomian glands can sometimes become blocked. What is the term used to describe this and what is a clinical sign?
Meibomian cyst
Clinical sign = localised thickening of the eyelid
Where is the lacrimal gland found? Describe it.
Lateral and high up
It is a small, flat gland with lots of little ducts
What is the conjunctival sac?
space between eyelids and front of eyes (tears from lacrimal gland drain into here)
Infection of conjunctiva is what?
Conjunctivitis
The roof of the orbit is made from what bone mainly?
Frontal bone
If someone has had facial trauma and injury to medial parts of eye, what might have happened?
Might have trauma to the lacrimal cuniculi (which drain the tears away) which may cause a fistula where tears escape in the long run
What are the muscles of the eye that can be seen from a dissection from above?
- Superior oblique muscle
- Superior rectus
- Levator palpebrae superioris
- Lateral rectus muscle
What is the function and nerve supply of the superior oblique muscle?
- Abducts, depresses and internally rotates eyeball
- Nerve supply = trochlear nerve (CNIV)
What is the function and nerve supply of the lateral rectus muscle?
Function = abduction of the eyeball (away from midline)
Nerve supply = abducens
What is the function and nerve supply of the superior rectus muscle?
function- elevation and adduction (inward, rotational movement)
Nerve = oculomotor
What is the function and nerve supply of the levator palpebrae superioris muscle?
Elevation of the upper eyelid
Nerve - oculomotor nerve
What are the special sweat glands in the eye called?
Glands of moll
have ducts that become blocked - looks like watery cysts
The upper eyelid gives lymph to where?
Parotid lymph nodes
If you have a droopy eyelid, what nerve is responsible?
Oculomotor (innervated levator palpebrae superioris which elevates upper eyelid)
What is the function and nerve supply of the medial rectus?
function = adduction (movement inwards to midline) nerve supply = oculomotor
If a patient can’t turn eye inwards, what nerve and muscles have been affected?
Oculomotor
and medial rectus muscles involved in adduction (moving eye inwards) and supplied by oculomotor nerve)
What is horners syndrome and clinical symptoms?
Horner’s syndrome = damage to the cervical sympathetic trunk (no sympathetic supply to affected region)
Clinical symptoms = Drooping eyelid and constricted pupil when compared to opposite side. Lack of sweating
