The Eye in General Disease Flashcards
What occurs in diabetic retinopathy?
Chronic hyperglycaemia causes glycosylation of protein/basement membrane
What does the loss of pericytes due to glycosylation in diabetic retinopathy cause?
Microaneurysms = may leak or cause ischaemia
What are the signs of non-proliferative diabetic neuropathy?
Microaneurysms, dot/blot haemorrhages, cotton wool patches, hard exudate, abnormalities of venous calibre, intra-retinal microvascular abnormalities (IRMA)
Where can new vessels grow in diabetic retinopathy?
On the disc (NVD), in the periphery (NVE) or on the iris (if ischaemia is severe)
Why do diabetic patients ultimately loss their vision?
Retinal oedema affecting the fovea, vitreous haemorrhage, scarring/tractional retinal detachment
What is the classification of retinopathy?
No retinopathy
Mild retinopathy
Moderate and severe = non-proliferative retinopathy
Proliferative retinopathy
What is the classification of maculopathy?
No maculopathy
Observable maculopathy
Referable maculopathy
Clinically significant maculopathy
What are the management options for diabetic retinopathy?
Laser = PRP, macular grid Surgery = vitrectomy Rehabilitation = blind/partial sighted
What part of the eye correlates the severity of hypertension and the state of the retinal arterioles?
The appearance of the fundus
How does age affect how hypertension impacts the eye?
Young people can have extensive retinopathy
Elderly patients with arteriosclerotic vessels often have minimal changes
What are some features of hypertensive retinopathy?
Attenuated vessels (copper/silver wiring), cotton wool spots, hard exudates, retinal haemorrhage, optic disc oedema
What are some features of accelerated hypertension?
Particularly affects young patients, very dramatic fundal appearance, can have decreased vision
What are some features of central artery occlusion?
Sudden painless loss of vision, profound visual loss, retinal nerve fibre layer except fovea (cherry red spot), rarely recovers
What are some features of central vein occlusion?
Sudden painless visual loss, range of visual loss, need to determine degree of ischaemia
What does the ischaemia that occurs due to central vein occlusion correlate to?
The degree of reduced vision and fundal appearances
What are some symptoms of branch vein occlusion?
Painless disturbance in vision, may be asymptomatic, may be aware of loss of part of visual field
What are some infective causes of uveitis?
TB, herpes zoster, toxoplasmosis, candidiasis, syphilis, lyme disease
What are some non-infective causes of uveitis?
Juvenile arthritis, idiopathic, sarcoidosis, Behcet’s disease, HLA-B27
What is giant cell arteritis?
Inflammation of medium sized arteries associated with polymyalgia rheumatica
What are some features of giant cell arteritis?
Headache, jaw claudication, malaise, raised PV, may cause blindness
What are some extra-ocular symptoms of thyroid eye disease?
Proptosis, restrictive myopathy
Lid involvement = retraction, oedema, lag, pigmentation
What are some ocular features of thyroid eye disease?
Anterior segment = chemosis, injection, exposure, glaucoma
Posterior segment = choroidal folds, optic nerve swelling
What characterises thyroid eye disease?
Swelling of the extra-orbital muscles and orbital fat
What is the underlying mechanism behind thyroid eye disease?
Autoimmunity = spectrum of severity, potential blinding complications
What is the most common cause for unilateral and bilateral proptosis?
Thyroid eye disease
How is thyroid eye disease managed?
Control of thyroid dysfunction, lubricants, surgical decompression
What are some features of SLE?
Multi-system autoimmune disease, anti-DNA antibodies, ocular inflammation
How does rheumatoid arthritis affect the eye?
Dry eyes (keratoconjunctivitis sicca), scleritis, corneal melt
How does Sjogren’s syndrome affect the eyes?
Keratoconjunctivitis sicca, xerostomia, rheumatoid arthritis, infiltration of lacrimal glands
What are some dermatological conditions that affect the eyes?
Erythema multiforme (Stevens-Johnson), hypersensitivity to drugs/food, maculopapular rash, stomatitis, conjunctivitis
How does Stevens-Johnson syndrome affect the eyes?
Symblepharon, occlusion of lacrimal glands, corneal ulcers
What vision problems are characteristic of Marfan’s syndrome?
Severe myopia, astigmatism
