Common Conditions of the Eye 2 Flashcards
What is the two pathologies of the cornea
Inflammatory
- corneal ulcers
Non inflammatory
- dystrophies
What is the aetiology of corneal ulcers
Infectious
Trauma
Corneal degeneration
Dystrophy
Why is it important to have aggressive management in dealing with infectious corneal ulcers
Prevent the spreading of infection
as if spreads below bowman capsule the healing process will involve scar tissue formation
What is the cause of dystrophies of the cornea
Due to opacifying
Genetics
Accumulation of lipids
What is the clinical presentation of corneal dystrophy
Happens in first to fourth decade
Decreased vision - bilateral
starts in one layer of the cornea and spreads to other
What is cataract
Lens opacification occurring with old age
What is the 3 pathologies that lead to cataract
New fibres formed from Basement membrane compact around old fibres - opaque
No blood supply dependant on nutrition from diffusion
absorbs harmful UV rays to protect the retina
What is the name of childhood cataract
sutural and zonular - formed due to the opacification of certain zones on the lens in utero
What is a differential diagnosis to cataract
Nuclear sclerosis
cloudy appearance but doesn’t affect vision
Why is it necessary to manage cataract
as if left untreated will result in loss of vision
How is cataract managed
Surgery(day case) small incision to open lens capsule cataractous lens removed by emulsification (phacoemulsification)
then Intra ocular lens is placed in the posterior chamber capsular bag
What is the two types of glaucoma
Open angle
Closed angle
What is the clinical presentation of glaucoma
Bilateral
Asymptomatic for a long period of time
Picked up on routine eye exam
What is glaucoma
Raised intraocular pressure resulting in field of vision loss
What is the pathology of open angle glaucoma
Trabecular meshwork isn’t working leading to the increase of intraocular pressure this causes damage to nerve fibres on surface of retina, nerve fibres eventually die out/lost resulting in blindness
What is the appearance on the ophthalmoscopy for glaucoma
optic disc appears unhealthy, pale and cupped
What is the triad of signs that lead to the diagnosis of glaucoma
Raised IOP
Visual field defects
Optic disc changes on ophthalmoscopy
What is the management for increased IOP
Eye drops to decrease IOP - Prostaglandin analogues - Beta-blockers - Carbonic anhydrase inhibitors Laser trabeculoplasty Trabeculectomy surgery
What is the symptoms of angle closure glaucoma
Sudden onset, painful,
vision lost/ blurred
headaches (often confused with migraine
What is seen on examination of closed angle glaucoma
Red eye,
Cornea often opaque
Why is the cornea obliwue in closed angle glaucoma
Raised IOP drive fluid into cornea
What affect does angle closed glaucoma have on the pupil and iris anterior chamber
Pupil Mid-dilated
iris is pushed forwards so the anterior chamber is shallow
What is the pathology of closed angle glaucoma leading to increased intraocular pressure
Predisposed eye as aqueous produced doesn’t freely go from posterior chamber exit through the pupil
Pupil is mid dilated causing periphery of iris to crowd and obstruct outflow
so aqueous humour fail to reach trabecular mesh work/AC
Then the iris sticks to pupillary boarder and balloons anteriorly obstructing angle
This raises the intraocular pressure driving aq humour into the cornea
What are the two methods an acute episode of glaucoma (closed angle0 is managed
Decrease IOP
Iridotomy - laser
