Ophthalmology - Loss of Vision Flashcards
What is used for examination of loss of vision?
Best corrected visual acuity
Snellen chart
Fundal exam
Ancillary tests
What does a fundal examination include?
Direct ophthalmoscope, slit lamp and volk lens
What are some ancillary tests?
Amsler chart
Colour vision
Visual field assessment
Fluorescein angiography
Optical coherence tomography
Describe a asmler chart
Usually taken home
Look at central spot one eye at time and see if there is distortion
If changed then alert for eye exam
What does colour vision assess?
Optic nerve and red + green colour blindness
Describe fluorescein angiography
Retinal conditions and dye injected
Arteries appear white first then after time veins
Describe optical coherence tomography
Cross section of retina and good for macula conditions
Can see fovea
Describe central retinal artery occlusion
Sudden complete loss of vision due to vascular reasons
Cherry red spot as perfusion of macula by choroidal vessels
Detect CVS risk factors
What is the management for central retinal artery occlusion?
CROA
Identify and treat CV risk factors
Aspirin sometimes given
Describe branch retinal artery occlusion
Emboli can be seen on fundal exam
Pale artery
Treated same as CROA
Identify and treat CV risk factors
Describe central retinal vein occlusion
CRVO - vein drains blood of all of retina
Haemorrhages may be seen and in all 4 quadrants may develop macular oedema
What is the management for central retinal vein occlusion?
Identify and treat risk factors
Intravitreal anti Vegf if macular oedema
What are the 2 types of anterior ischaemic optic neuropathy (AION)?
Arteritic - giant cell arteritis (optic nerve is pale and borders indistinct)
Non arteritic
What are the signs and symptoms of giant cell arteritis?
Loss of vision, unilateral headache, loss of appetite, scalp tenderness and jaw claudication
Tenderness of superficial temporal arteries, raised CRP, ESR and platelets
What is the management of giant cell arteritis?
High dose systemic steroids - oral prednisolone
Describe non arteritic anterior ischaemic optic neuropathy?
Painless
Half of vision can be missing, disc is swollen, raised CV risks
Management is identify and treat CV risk factors
What can cause a vitreous haemorrhage?
Posterior vitreous detachment
Proliferative diabetic retinopathy
Trauma
Causes rapid loss of vision
What is the management of vitreous haemorrhage?
Conservative or vitrectomy - remove VH and blood
What are the risk factors for retinal detachment?
Myopia, trauma and cataract surgery
Describe retinal detachment
Have realised flashing lights and floating spots in vision
If caught early with no detachment just tear then managed with laser retinal pelxi
Surgical repair is needed
What could cause a gradual loss of vision?
Cataract, glaucoma, age related macular degeneration and diabetic retinopathy
What are the symptoms of cataracts?
Loss of vision and dazzle/gaze especially at night/ evening
What is the management for cataracts?
Surgery - phacoemulsification with intraocular lens implant
What is a glaucoma?
Optic neuropathy with typical optic nerve damage and associated field changes usually associated with raised IOP
Open or closed angle and can be chronic or acute
What are the symptoms of a glaucoma?
Asymptomatic, gradual loss of peripheral field of vision
Presents usually later symptoms
What are the signs of chronic glaucoma?
Raised IOP, visual field defects and optic nerve damage
What is the management for chronic glaucoma?
Topical treatment - prostaglandins, BB and carbonic anhydrase inhibitors
Surgery - trabeculectomy and drainage services
What are the symptoms of age related macular degeneration?
Progressive loss of central vision and distortion
Can be wet or dry (mainly dry)
Wet is more significant
What are the signs of age related macular degeneration?
Distortion on amsler chart
Drusen - yellow patched on fundoscopy (calcium and protein deposits)
Normal retina and Atrophy in dry
What is the management of dry age related macular degeneration?
Low vision aids
Registration - sight impaired SSI
Describe wet age related macular degeneration
Neovascular
Choroidal new vessels
Bleeding out of abnormal vessels at macula
What investigations are used for wet age related macular degeneration?
OCT - macular oedema may be seen
Fluorescein angiography - hyperfluorescent shows leakages
What is the management of wet age related macular degeneration?
Intravitreal antivegf
Low vision aids
Registration - SI/SSI
What are the signs of diabetic retinopathy?
Gradual loss of vision
Microaneurysms
Retinal haemorrhages and exudates
Neovascularisation
What are the investigations for diabetic retinopathy?
Fluorescein angiography
OCT - macular oedema
What is the management of diabetic retinopathy?
Control BP, BM and cholesterol
Intravitreal antivegf
Laser - panretinal phtocoagulation
Low vision aids
Registration
