Opth- other visual defects Flashcards
what is glaucoma
a group of chronic diseases characterised by a progressive optic neuropathy resulting in characteristic field defects
modifiable risk factor of glaucoma
intra-ocular pressure
non-modifiable risk factors of glaucoma
increased age
myopia
afro-caribbean ethnicity
what are open angled glaucomas the result of
poor drainage through the trabecular meshwork
what is Rubeotic glaucoma
new vessel formation in diabetic eye disease forms obstructive angle
signs of closed angle glaucoma
red eye
cloudy cornea
dilated pupil
symptoms of open angle glaucoma
usually asymptomatic
first line treatment for open angled glaucoma
prostanoids eg latanoprost (xalatain)
second line treatment for open angled glaucoma
beta blockers, carbonic anhydrase inhibitors
what is the definitive management of closed angle glaucoma
laser peripheral iridotomy
what are cataracts
opacifications within the lens
what accounts for 50% of all causes of blindness worldwide
cataracts
risk factors of cataracts
UVB damage
hypertension
smoking
post operative and trauma
steroids
metabolic disorders eg diabetes
genetic
management of cataracts
surgical removal with intra-ocular lens transplant if patient is symptomatic
complications of cataract surgery
Posterior capsule opacification: thickening of the lens capsule
retinal detachment
posterior capsule rupture Endophthalmitis
what are refractive errors
refers to any abnormalities in focusing mechanism of the eye
what is emmetropia
‘perfect vision’- no refractive error, light focused on retina
what is ametropia
refractive error, light focused in front of retina or behind retina
what is animoetrophia
significant difference between the right and left ametropia
where do light rays focus in myopia
light rays focus in front of retina
where do light rays focus in astigmatism
light rays focus on more than one point
where do light rays focus in hypermetropia
light rays focus behind the retina
what is myopia aka
short sightedness
complications of myopia related to large eyeball size
retinal detachment
primary open-angle glaucoma
what glasses do people with myopia wear
glasses with concave (negative) lenses
what is hyperophia aka
far-sightedness
what glasses do people with hyperopia wear
glasses with convex (positive) lenses
complications of hyperopia related to small eyeball size
closed angle glaucoma
what is the management of astigmatism
cylindrical lenses
what is presbyopia
age-related degeneration of structures responsible for accommodation of the lens
risk factors of strabismus (squint)
premature birth
cerebral palsy
family history
