Common Conditions of the Eye Flashcards
26 year old male complaining of double vision.
On questioning, he mentions that he was in a fight 2 weeks ago.
what would you ask him to do?
You question him further and he mentions that he was in a fight two weeks ago.
3:27
Yeah he said, I was outside the pub and I picked up this fight with this other chap and he punched me, he said
3:32
he punched me and my left eye was blue for a few days, but it’s all gone now
while the bruising on the eyelids and around the orbit has healed, the floor of the orbit would have got fractured.
6:45
And some of the inferior content of his left eye would have got tethered in that fracture, which is why he’s unable to look up.
6:53
But his inability to look up is not because the superior rectus or the inferior oblique are paralysed,
7:02
They are mainly because the muscles here are tethered in the orbital blow out fracture.
7:09
You can diagnose that with imaging such as C.T. scans
the inferior orbital groove and fissure transmits a branch of the maxillary division of the trigeminal nerve.
8:16
And you have the infraorbital foramen through which the infraorbital nerve, a sensory nerve to this region here emerges from there.
8:28
So when you’ve got a fracture of the floor, it’s quite common for that nerve to get damaged as well.
8:37
And so one of the signs you might find in this gentleman is when you test for sensations,
8:43
when you use a little, maybe a cotton bud, you test the sensation here,
8:49
that’s normal, but you test the sensation here on this side and it is lost.
8:54
Okay, so blow out fracture, something that’s happened because the rim of the orbit is strong, but the walls are weakened.
Once asking case one to move his eye you find…
His right eye is moving absolutely fine. But when you asked him to look up, you find that the left eye does not move up at all
And this is the same situation when he’s looking up and to the right or up and to the left as well; with the right eye moving absolutely fine,
the left eye finding it difficult to get elevated
what could cause this?
paralysis of the superior rectus and or the inferior oblique muscles - muscles that cause elevation
why is case one not cranial nerve 3 palsy?
the superior rectus is innervated by the third nerve, the inferior oblique is also innervated by the third nerve
but there is no other palsy of any of the other muscles innervated by the third nerve.
You question case one further and he mentions that he was in a fight two weeks ago.
he punched me and my left eye was blue for a few days, but it’s all gone now
while the bruising on the eyelids and around the orbit has healed, the floor of the orbit would have got fractured.
what is the diagnosis?
blow out fracture - the floor of the orbit would have got fractured.
some of the inferior content of his left eye would have got tethered in that fracture, which is why he’s unable to look up.
But his inability to look up is not because the superior rectus or the inferior oblique are paralysed,
They are mainly because the muscles here are tethered in the orbital blow out fracture.
blow out fracture, something that’s happened because the rim of the orbit is strong, but the walls are weakened.
how is a blow out fracture diagnosed?
You can diagnose that with imaging such as C.T. scans
what sensation is commonly affected by a blow out fracture?
the inferior orbital groove and fissure transmits a branch of the maxillary division of the trigeminal nerve.
And you have the infraorbital foramen through which the infraorbital nerve, a sensory nerve to this region here emerges from there.
So when you’ve got a fracture of the floor, it’s quite common for that nerve to get damaged as well.
And so one of the signs you might find in this gentleman is when you test for sensations,
when you use a little, maybe a cotton bud, you test the sensation here,
that’s normal, but you test the sensation here on this side and it is lost.
what other feature is commonly seen in blow out fractures?
teardrop sign
what conditions cause orbital fat hypertrophies?
Orbital fat hypertrophies in certain conditions like thyroid diseases leading to the staring appearance
proptosis
A previously well 23 year old woman attended A&E with a two hour history of blurred vision and a red and swollen eye
O/E: red, painful no eye movement. Progressed within an hour to complete loss of vision.
History elicited of having squeezed a pimple near her left nasolabial fold 3 days prior
what is your diagnosis?
squeezed a pimple in the danger triangle, infection has spread through valveless emissary veins to the cavernous sinus leading to cavernous sinus thrombosis
what is cavernous sinus thrombosis?
a blood clot in the cavernous sinuses. It can be life-threatening. The cavernous sinuses are hollow spaces located under the brain, behind each eye socket. A major blood vessel called the jugular vein carries blood through the cavernous sinuses away from the brain
fever, headache (50% to 90%), periorbital swelling and pain, vision changes, such as photophobia, diplopia, loss of vision
requires surgical sinus drainage
what is the function of the obliques of the eye?
elevate and depress when eye is adducted
what is the function of the recti of the eye?
elevate and depress when eye is abducted
what are the symptoms of sixth cranial (abducens) nerve palsy?
what are the symptoms of third cranial nerve (occulomotor) palsy?
what are the symptoms of right fourth cranial nerve palsy?
what are some common causes of absent/abnormal pupillary reflex?
what is the conjunctiva?
thin vascular membrane that covers inner surface of eyelids and loops back over sclera
what does conjunctiva not cover!
cornea
label different parts of the lids and conjunctiva?
what is ptosis?
drooping of the eyelid
what may cause the appearence of a drooping eyelid?
third cranial nerve palsy
what are the symptoms of seventh cranial (facial) nerve palsy?
describe the histological features of the cornes?
Epithelium – stratified squamous non-keratinised.
what is a corneal ulcer?
Infectious - Viral/ bacterial/ fungal infection of cornea. Needs aggressive management to prevent spread, scarring.
Non-infectious ulcers due to trauma, corneal degenerations or dystrophy.
what are types of childhood cataract?
what are some forms of secondary cataracts?
what are the triad signs for diagnosis of glaucoma?
desciribe the differences between open and closed angle glaucoma?
