Ophthalmology Flashcards
What is the cause of diabetic retinopathy?
- blood vessels damaged by hyperglycaemia causing damage to the retina
Describe the pathophysiology of diabetic retinopathy
- increased vascular permeability leads to leakage from the blood vessels, causing blot haemorrhages and the formation of hard exudates
- damage to the blood vessel wall leads to microaneurysms and venous beading
- damage to nerve fibres in the retina causes fluffy white patches to form on the retina called cotton wool spots
- intracranial microvascular abnormalities is where there are dilated and tortuous capillaries in the retina. Act as a shunt between the arterial and venous vessels in the retina
- neovascularisation
What are the different types of retinopathy and how can we classify them?
- non proliferative and proliferative
- Non-proliferative is microaneurysms, blot haemorrhages, hard exudates and if severe can also have cotton wool spots and venous beading
- proliferative is when there is also neovascularisation
- diabetic maculopathy is specifically when the macula is affected
Complications of diabetic retinopathy
- retinal detachment
- vitreous haemorrhage
- rebeosis iridis (new blood vessel formation)
- optic neuropathy
- cataracts
How is diabetic retinopathy managed?
- laser photocoagulation
- anti-VEGF (ranibizumab, bevacizumab)
- vitreoretinal surgery for severe disease
What is uveitis?
- inflammation of the iris and ciliary body and choroid
What causes uveitis?
- infection (e.g. herpes simplex), trauma, ischaemia or malignancy
- can occur as a manifestation of systemic inflammatory conditions (reactive arthritis, ankylosing spondylitis, inflammatory bowel disease, sarcoidosis)
What associations does uveitis have?
- Anterior is associated with HLA B27 conditions (ankylosing spondylitis, IBD, reactive arthritis)
- Chronic anterior uveitis (sarcoidosis, syphilis, lyme disease, tuberculosis, herpes virus)
Presenting symptoms of uveitis
- unilateral symptoms
- may occur with a flare of an associated disease such as reactive arthritis
- dull, aching, painful red eye
- ciliary flush
- reduced visual acuity
- miosis
- photophobia
- pain on movement
- excessive lacrimation
- abnormally shaped pupil
- hypopyon
How should uveitis be managed?
- steroids (oral, topical or IV)
- cyclopentolate
- immunosuppressants such as DMARDS or TNF inhibitors
What is scleritis?
inflammation of the full thickness of the sclera
What are the associated symptoms of scleritis
- RA
- SLE
- IBD
- sarcoidosis
- granulomatosis with polyangiitis
How does scleritis present?
- severe pain
- pain with movement
- photophobia
- eye watering
- reduced visual acuity
- abnormal pupil reaction to light
- tenderness to palpation of the eye
How is scleritis managed?
- NSAIDs
- Steroids
- Immunosuppression
What are the 3 types of conjunctivitis?
- bacterial
- viral
- allergic
How does conjunctivitis present?
- unilateral or bilateral
- red eyes
- bloodshot
- itchy or gritty sensation
- discharge from the eye
Difference between viral and bacterial conjunctivitis?
Bacterial = purulent discharge, worse in morning where eyes may be stuck together, starts in one eye and can spread to others
Viral = clear discharge, dry cough, sore throat and blocked nose, preauricular lymph nodes
How should conjunctivitis be managed?
- usually resolves without treatment after 1-2 weeks
- good hygiene
- stop contacts
- clean eyes
Bacterial = consider antibiotic eyedrops (chloramphenicol)
Under 1s = urgent review as it can be associated with gonococcal infection
Allergic = antihistamines, topical mast-cell stabilisers
Why is neonatal conjunctivitis an urgent issue?
- associated with gonococcal infection and can cause loss of sight and more severe complications such as pneumonia
