Eye Flashcards
What would you see in retinal artery occlusion and what would you treat with?
You may see retinal oedema with red cherry spot and pale disc (late manifestatio)
Treat with ocular massage
Acetazolamide
Paracentasis
How do you diagnose and treat Open angle glaucoma?
Goldmann applanation tonometry
Beta blockers- timolol (reduce production)
Carbonic anhydrase inhibitors- reduce production of aqueous humour
Brimonidine
Trabeculectomy surgery may be required where eye drops are ineffective
What is the pathophysiology of open angle glaucoma?
In open-angle glaucoma, there is a gradual increase in resistance through the trabecular meshwork. This makes it more difficult for aqueous humour to flow through the meshwork and exit the eye. Therefore the pressure slowly builds within the eye and this gives a slow and chronic onset of glaucoma.
What do you see on fundoscopy with Open angle glaucoma?
Cupping
How do you manage AACG?
NICE CKS 2019 say patients with potentially life-threatening causes of red eye should be referred for same-day assessment by an ophthalmologist. If there is a delay in admission, whilst waiting for an ambulance:
Lie patient on their back without a pillow
Give pilocarpine eye drops (2% for blue, 4% for brown eyes)
Give acetazolamide 500 mg orally
Given analgesia and an antiemetic if required
Laser iridotomy is usually required as a definitive treatment. This involves using a laser to make a hole in the iris to allow the aqueous humour to flow from the posterior chamber into the anterior chamber. The relieves pressure that was pushing the iris against the cornea and allows the humour the drain.
What investigations should you do for age related macular degeneration?
Reduced acuity using a Snellen chart
Scotoma (a central patch of vision loss)
Amsler grid test can be used to assess the distortion of straight lines
Fundoscopy. Drusen are the key finding.
Slit-lamp biomicroscopic fundus examination by a specialist can be used to diagnose AMD.
Optical coherence tomography is a technique used to gain a cross-sectional view of the layers of the retina. It can be used to diagnose wet AMD.
Fluorescein angiography involves giving a fluorescein contrast and photographing the retina to look in detail at the blood supply to the retina. It is useful to show up any oedema and neovascularisation. It is used second line to diagnose wet AMD if optical coherence tomography does not exclude wet AMD.
How do you treat wet AMD and dry AMD?
There is no specific treatment for dry age-related macular degeneration. Management focuses on lifestyle measure that may slow the progression:
Avoid smoking
Control blood pressure
Vitamin supplementation has some evidence in slowing progression
Wet AMD
Anti-VEGF medications are used to treat wet age-related macular degeneration. Vascular endothelial growth factor is involved in the development of new blood vessels in the retina. Medications such as ranibizumab, bevacizumab and pegaptanib block VEGF and slow the development of new vessels. They are injected directly into the vitreous chamber of the eye once a month. They slow and even reverse the progression of the disease. They typically need to be started within 3 months to be beneficial.
What are the complications of diabetic retinopathy?
Retinal detachment
Vitreous haemorrhage (bleeding in to the vitreous humour)
Rebeosis iridis (new blood vessel formation in the iris)
Optic neuropathy
Cataracts
What is the management of diabetic retinopathy?
Laser photocoagulation
Anti-VEGF medications such as ranibizumab and bevacizumab
Vitreoretinal surgery (keyhole surgery on the eye) may be required in severe disease
What is the difference in vision changes with macular degeneration, glaucoma and cataracts?
. Cataracts cause a generalised reduction in visual acuity with starbursts around lights. Glaucoma causes a peripheral loss of vision with halos around lights. Macular degeneration causes a central loss of vision with a crooked or wavy appearance to straight lines.
How do you treat scleritis?
Consider an underlying systemic condition
NSAIDS (topical / systemic)
Steroids (topical / systemic)
Immunosuppression appropriate to the underlying systemic condition (e.g. methotrexate in rheumatoid arthritis)
