Common Conditions of the Eye Flashcards
What is the consequence of the bony orbit having very thin walls?
Can get herniation of contents into surrounding sinuses usually maxilla - due to fractures
Muscles are tethered so eye does not move
How is a blow out fracture diagnosed?
CT scan - teardrop sign
What does orbital fat hypertrophy lead to?
Leads to staring appearance - proptosis
Can be due to thyroid diseases
Can also cause scleral show
What can infection spread from emissary veins to cavernous sinus cause?
Can lead to cavernous sinus thrombosis as travelled from danger area of face
CN4,5,6 affected and causes swelling
Blindness can be caused due to lack of blood supply
What are the symptoms of CN VI palsy?
LR affected as abducent nerve
Eye can adduct but cant abduct
What are the symptoms of CN III palsy?
Eyelid drooping and all muscles affected except SO and LR
Pupillary reflex is tested - large and unreactive
Ptosis
What are the symptoms of CN IV palsy?
SO affected as trochlear nerve
Eye shoots up as result
As adducting the IR is over reacting
SO muscle is paralysed
What can blunt trauma to the eye cause?
Peripheral retina to tear
Vitreous gel gets liquefied
Liquid vitreous pushes through retinal tear which detaches it
What is coloboma?
Congenital malformation of eye causing defects in iris, retina and optic disc
What is the conjunctivae?
Thin vascular membrane covering inner surface of eyelids and loops back over sclera
Does not cover the cornea
Describe conjunctivitis
Self limiting bacterial or viral infection of conjunctivae
Red, watering eye with discharge
No loss of vision as long as the infection does not spread to cornea
What is the treatment for conjunctivitis?
Antibiotic eye drops if likely to be bacterial
What might cause drooping eyelid (ptosis)?
CNIII dystrophy or paralysis
What could cause inability to close eyelid?
CN VII facial nerve palsy
Check other facial nerves
Causes extreme drying and conjunctivitis - ulceration of cornea
Describe a stye/ hordeolum
External stye - hordeolum externum
Infection of hair follicle of eyelash
Internal stye - hordeolum internum
Blockage and infection of Meibomian gland
What is the treatment for a stye?
Warm compress, eyelid hygiene and may need surgical incision and curettage