Gradual Vision Loss Flashcards
pneumonic for causes of gradual vision loss
CARDIGAN
Cataracts
Age related macular degeneration (dry)
Refractive Error
Diabetic Retinopathy
Inherited Disease
Glaucoma (Open angle)
Access to eye clinic (non-urgent)
what is cataracts
gradual clouding of the lens
what can cause cataracts
age related - denaturing of lens protein as part of ageing
congenital - screened for with red reflex during neonatal exam
diabetes
steroids
trauma
key sign in cataracts
diminished/ loss of red reflex
symptoms of cataracts
gradual painless decrease in visual acuity
faded colour vision
glare - lights seem brighter
haloes around lights, particularly at night
treatment of cataracts
cataract surgery - removal of lens and replacing with artificial one
- endopthalmitis is a rare but serious complication
pathological hallmark of dry age related macular degeneration
drusen - yellow deposits of lipids / proteins
symptoms of dry age related macular degeneration
gradual painless loss of central vision
distortion of straight lines
management of dry age related macular degeneration
irreversible damage - treatment based on supporting the remaining vision the patient has left
what is a refractive error
eye’s inability to clearly focus on an image
e.g. hypermetropia, myopia, astigmatisms
what is astigmatism? what are the symptoms?
abnormal curvature of the cornea
- causes two focal points of light on the retina instead of one
blurry vision, headaches, eye strain
how is a refractive error corrected
glasses
contact lenses
laser eye surgery for permanent correction of vision
pathophysiology of diabetic retinopathy
hypercalcaemia causes:
- epithelial dysfunction: increased vascular permeability – haemorrhages + exudate formation
- pericyte dysfunction: microaneurysms
classifications of diabetic retinopathy
non-proliferative (mild, moderate, severe)
proliferative
what is seen in mild diabetic retinopathy
microanuerysms
what is seen in moderate diabetic retinopathy
microanuerysms
blot haemorrhages
hard exudates
cotton wool spots
what is seen in severe diabetic retinopathy
blot haemorrhages
microaneurysms in 4 quardrants
venous bleeding in 2 quadrants
intraretinal microvascular abnormality (IRMA) in any quadrant
features of proliferative diabetic retinopathy
neovascularisation
vitreous haemorrhage
complications of diabetic retinopathy
retinal detachment
vitreous haemorrhage
optic neuropathy
cataracts
treatment of diabetic retinopathy
laser photocoagulation
anti-VEGF
Vitreoretinal surgery in very severe disease
what is diabetic maculopathy
macula oedema + ischaemic changes
tx: laser surgery
what causes an open angle glaucoma
gradual rise in IOP due to resistance in the trabecular meshwork
risk factors for open angle glaucoma
increased age
myopia
black ethnicity
family history
symptoms of open angle glaucoma
gradual decrease in peripheral vision – tunnel vision
gradual onset of fluctuating headaches, pain, blurred vision, haloes around lights
how is intra occular pressure measured?
what is normal range?
tonometry
10-21mmHg
signs of raised IOP on fundoscopy
optic disc cupping - indent in the middle of optic disc, should be less than half the size of the disc. Cup - disc ratio >0.7 = abnormal
optic disc colour- pale = optic atrophy
1st line treatment of open angle glaucoma
latanoprost (prostaglandin analogue)
how does latanoprost work
increaeses uveoscleral outflow
side effects of latanoprost
eyelash growth
eye lid pigmentation
browning of iris
2nd line treatment options of open angle glaucoma
beta blockers (timolol) - decrease aqueous humour production
carbonic anydrase inhibitors (dorzolamide) - decrease aqueous humour production
miotics (pilocarpine)- increase uveoscleral outflow
treatment of open angle glaucoma if topical therapy ineffective
trabelectomy surgery
what is retinitis pigmentosa
inherited condition where there is degeneration of rods + cones in the retina
symptoms of retinitis pigmentosa
night blindness- often first symptom
peripheral vision lost first, before central vision
- tunnel vision
signs of retinitis pigmentosa on fundoscopy
black bone spiculae pigmentation on peripheral retina
what is Usher’s syndrome
retinitis pigmentosa + hearing loss
