Common Conditions of the Eye Flashcards
What is a cataract?
An opacification of the lens
Why do cataracts develop?
Older fibres never shed, compacted in middle
Absorbs harmful UV rays and get damaged
What does cataracts initially look like?
Spoke like opacities
What type of cataracts occur during childhood?
Sutural
Zonular
Why must childhood cataracts be treated aggressively?
Brain will suppress the image formed on the retina in that eye, will adjust to lower image acuity
How are cataracts treated?
Surgery (cataractous lens removed by emulsification, plastic lens placed in capsular bag)
What is glaucoma?
Raised intraocular pressure
What are the 2 types of glaucoma?
Primary open angle glaucoma
Angle closure glaucoma
What are the consequences of raised intraocular pressure?
Pressure on optic nerve head and nerve fibres on retina surface, die out causing altered field of vision or blindness
How are primary open angle glaucomas managed?
Eye drops decrease pressure
Laser trabeculectomy
Trabeculectomy surgery
What are the symptoms of angle closure glaucoma?
Sudden onset
Pain
Vision loss/blurred
Headaches (often confused as migraines)
What are the clinical signs of angle closure glaucoma?
Red eye
Cornea often opaque
Pupil mid dilated
IOP severely raised
Why does the angle close to cause glaucoma?
Periphery of iris crowds around angle, outflow is obstructed
Iris sticks to pupillary border which prevents reaching AC
How do you manage an acute episode of glaucoma?
Decrease IOP with IV infusion, constructor eye drops, steroid eye drops
Iridotomy
What type of epithelium is present on the cornea?
Stratified squamous non-keartinised
What are the causes of corneal ulcers?
Trauma
Corneal degenerations/dystrophy
Viral/bacterial/fungal infections
How do corneal dystrophies present?
Decreased vision
What is a lattice (stromal) dystrophies?
Deposition of amyloid material in corneal stroma
How do lattice dystrophies present?
Eye irritation
Photosensitivity
Pain
Blurred vision
What is a Fuch’s endothelial dystrophy?
Destruction and death of endothelial cells causing progressive bilateral oedema
How are dystrophies managed?
Symptom mangement
Corneal transplant in later stages
What is the surgical benefit of corneal transplantation?
Avascularity means lesser chance of foreign antigens from graft being recognised by recipient so lesser chance of rejection
What is uveitis?
Inflammation of uvea
Where would you find the different types of uveitis?
Anterior - Iris with or without ciliary body
Intermediate - ciliary body
Posterior - Choroid
What are the causes of uveitis?
TB
Ankylosing spondylosis
Autoimmune causes
What happens in anterior uveitis?
Uvea leaks plasma and white blood cells into the aqueous humour
What is seen on examination of an anterior uveitis?
Hazy anterior chamber
Cells deposited at back of the cornea
What are the symptoms of anterior uveitis>
Eye is red, painful
Visual loss
What is seen on examination of intermediate and posterior uveitis?
Hazy vitreous
What are the symptoms intermediate/posterior uveitis?
Hazy vision
What are the symptoms of conjunctivitis?
Red, watering eyes
Discharge
No loss of vision
What is the treatment for conjunctivitis?
Antibacterial eye drops if the cause is bacterial
What is the tarsal plate?
Connective tissue which helps evert the eyelids
What is the cause of an external stye?
Infection of the hair follicle of the eyelash
What is the cause of an internal stye?
Blockage and infection of the Meibomian glands
