The Eye and Systemic Disease Flashcards
How does the retina appear in diabetic retinopathy?
- White spots are scars from laser treatment
- Yellow stuff is lipid layed macrophages -> called exudates
- Retina should be transparent – the choroid is pink – in DR it looks yellow
Describe the pathogenesis of diabetic retinopathy
- Chronic hyperglycaemia
- Glycosylation of protein/basement membrane
- Loss of pericytes* leads to small microscopic outpouchings of the retina -> microaneurysm
- Microaneurysm can lead to leakage + ischaemia
- Pericyte = contractile cells that wrap around the endothelial cells that line the capillaries and venules throughout the body.
- Ischaemia leads to new vessel formation
Describe some retinal signs of non-proliferative retinopathy
- Microaneurysms / dot + blot haemorrhages
- Hard exudate (this is blot haemorrhages)
- Cotton wool patches (these are just thickened axons)
- Abnormalities of venous calibre
- Intra-retinal microvascular abnormailities (IRMA – this is just a term for venous bleeding)
- Macroaneurysm – small red dot on retina with blank patch around it
Describe the pathophysiology of neovascularization in DR
- Haemorrhage on retina
- Supply demand mismatch – photoreceptors need more oxygen (i.e. they are ischaemic) , so send out signalling molecules leading to neovascularization
- New blood vessels are not surrounded by pericytes -> not competent, leaky, fragile
- New vessel formation brings a massive scarring response
What is rubeosis iridis?
Neovascularization of the iris - you cannot recover from this
What are the three things that diabetic patients lose their vision from?
- Retinal oedema affecting the fovea
- Vitreous haemorrhage
- Scarring/ tractional retinal detachment
How is diabetic eye disease classified according to retinopathy?
- No retinopathy
- Mild
- Moderate
- Severe
- Proliferative retinopathy
The midde three are classed as non-proliferative
How is diabetic eye disease classified according to maculopathy?
- No maculopathy
- Observable maculopathy
- Referable maculopathy
- Clinically significant maculopathy
Give some management options for diabetic retinopathy
- Optimise medical management
- Laser treatment - mismatch in supply in demand – drop the demand by reducing the metabolic rate of the retina i.e. you sacrifice the peripheral retina
- Surgery – vitrectomy
- Rehabilitation (blind/partial sighted)
- Anti-VGEF
Disc neovascularization can be treated with laser treatment.
How does the appearance of the fundus relate to severity of hypertension?
Appearance of fundus correlates to severity of hypertension and the state of the retinal arterioles.
How can the fundus of elderly vs young patient look in terms of hypertensive retinopathy?
Young people can have extensive retinopathy.
Elderly patients with arteriosclerotic vessels often have minimal changes.
NB – atherosclerotic changes look like hypertensive ones.
Give some fundus features of hypertensive retinopathy
- Attenuated blood vessels (narrowed blood vessels) -copper or silver wiring
- Cotton wool spots
- Hard exudates
- Retinal haemorrhage
- Optic disc oedema
Accelerated hypertension
- Who gets it?
- Fundus appearance?
- Vision?
- Particularly in young patients
- Very dramatic fundal appearance
- Can have decreased vision
What is the other name for neovascular glaucoma?
- Precipitating factor?
- Pathology?
- Symptoms?
Rubeotic eye
- Follows a severe retinal vein blockage or severe diabetic eye disease
- Growth factors from an ischaemic retina spread to the anterior chamber, where they meet the trabecular meshwork (drainage system)
- At the same time as blood vessels grow on the drainage system, they grow on the iris
- They block the drainage system to aqueous cannot drain and so pressure in the eye increases
- Pain and inflammation
Sarcoidosis causes inflammation of which part of the eye?
What other eye symptoms can sarcoidosis cause?
Uvea - choroid, ciliary body and iris
Periocular lesions may produce dry eye symptoms, as well as disfiguring lid, periocular, and adnexal lesions
What symptoms does uveitis cause?
include blurred vision, photophobia, floaters, redness, scotomata, and pain.
Giant cell arteritis
- Inflammation of which vessels?
- Associated with which condition?
- Symptoms?
- Inflammation of middle sized arteries
- Associated with polymyalgia rheumatica
- Headache
- Jaw claudication
- Malaise
- Raised P.V.
- Blinding Condition
Give some extra ocular features of thyroid eye disease
Proptosis – bulging of the eyes Lid signs - Retraction - Oedema - Lag - Pigmentation Restrictive myopathy
Give some ocular features of thyroid eye disease
Anterior segment - Chemosis - Injection - Exposure - Glaucoma Posterior segment - Choroidal folds - Optic nerve swelling
What is proptosis characterised by?
What type of condition is it caused by?
- Characterised by swelling of the extraocular muscles and orbital fat
- Autoimmune
- Most common cause of unilateral and bilateral proptosis
- Spectrum of severity
- Potential blinding complications
Treatment of thyroid eye disease?
- Control of thyroid dysfunction
- Lubricants
- Surgical decompression
Give three eye features of rheumatoid arthritis
- Dry eyes (Keratoconjunctivitis Sicca)
- Scleritis
- Corneal melt
Give two eye features of Sjogren’s disease
Keratoconjunctivitis sicca
Infiltration of the lacrimal glands
What eye problem does Marfan’s syndrome cause?
Dislocation of the lens
Give three eye features of Stevens-Johnson syndrome
- Symblepharon – partial or complete adhesion of the palpebral conjunctiva of the eyelid to the bulbar conjunctiva of the eyeball
- Occlusion of lacrimal glands
- Corneal ulcers
Which nerve is associated with visual field defects?
CN II - optic
Give four common aetiologies of visual field defects
- Vascular disease – CVA – can affect one optic nerve -> optic neuropathy, or stroke – bilateral visual field defect
- Space occupying lesion (SOL) – can affect anywhere in the tract
- Demyelination (MS)
- Trauma - including surgical
Give two things which commonly affect the optic nerve in visual field defect
Ischaemic optic neuropathy
Optic neuritis
What two types of visual field defect is an optic nerve problem likely to cause?
- Complete
2. Altitudinal - abide the horizontal - likely to be microvascular
Optic neuritis
- What type of visual loss?
- Pain?
- Other affects on vision?
- Recovery?
- Appearance on fundoscopy?
- Progressive visual loss (unilateral) – gradual but relatively quick
- Pain behind eye, especially on movement
- Colour desaturation
- Central scotoma
- Gradual recovery over weeks – months
- Optic atrophy - optic disc which is pale and featureless
How is optic neuritis distinguished from microvascular disease?
Affects people under 50 – distinguishes it from microvascular disease
Give some clinical features of optic tract/radiation defects
- Homonomous defects
- Macula not spared
- Quadrantanopia
- Incongruous
What does a meningioma in the optic tract/radiation cause in visual field?
Homonomous hemianopia
What visual field defect does pathology in the occipital cortex cause?
- Homonomous defect
- Macular sparing
- Congruous
