Important eye presentations

Question 1

Painful loss of vision

Answer 1

Trauma: corneal foreign body, corneal abrasion, traumatic hyphaema, penetrating injury, globe rupture.
Corneal ulcer.
Herpes simplex keratitis.
Anterior uveitis.
Endophthalmitis.
Scleritis.
Giant cell arteritis.

Question 2

Acute painless loss of vision

Answer 2

Vitreous haemorrhage.
Wet age-related macular degeneration.
Central or branch retinal vein occlusion.
Central or branch retinal artery occlusion.
Anterior ischaemic optic neuropathy.
Temporal arteritis or giant cell arteritis.
Retinal detachment

Question 3

Acute painless loss of vision: vitreous haemorrhage

Answer 3

Impaired or no fundal view, ± reduced red reflex.

Causes: retinal detachment, diabetic retinopathy.

Question 4

Acute painless loss of vision: central or branch retinal vein occlusion

Answer 4

Widespread or hemispheric retinal haemorrhages, ± cotton wool spots, exudates, disc swelling, macular oedema.
Common causes: hypertension, diabetes, hyperlipidaemia.
Other causes: vasculitis (e.g. Behçet’s, sarcoidosis, SLE), clotting disorders (e.g. protein S or C deficiency, antiphospholipid syndrome) multiple myeloma, glaucoma.

Question 5

Acute painless loss of vision: central or branch retinal artery occlusion

Answer 5

Sudden loss of vision, may have symptoms of GCA, 10% of patients have preceding amaurosis fugax.
Pale retina, cherry red spot, retinal vessel emboli.
Causes: atherosclerotic (hypertension, diabetes, smoking, hyperlipidaemia), embolic (carotid/aortic artery disease, cardiac valve disease), haematological (protein C deficiency, antiphospholipid syndrome, lymphoma, leukaemia), inflammatory (GCA, SLE, polyarteritis nodes, Wegener’s granulomatosis), other (oral contraceptive, trauma, migraine).

Question 6

Acute painless loss of vision: anterior ischaemic optic neuropathy

Answer 6

May be arteritic (temporal arteritis or GCA) or non-arteritic (hypertension, diabetes, anaemia, smoking, hyperlipidaemia).

Question 7

Acute painless loss of vision: temporal arteritis or giant cell arteritis

Answer 7

Headache, scalp tenderness, jaw claudication, neck pain, fever, malaise, joint pains.
Tender, non-pulsatile temporal artery, relative afferent pupillary defect, swollen optic disc, ± central retinal arterial occlusion, ± cranial nerve palsies.

Question 8

Acute painless loss of vision: retinal detachment

Answer 8

Floaters, flashing lights, loss of vision/visual field defect.
Ocular risk factors: history of trauma, cataract surgery, myopia.
Systemic risk factors: Stickler syndrome, Marfan’s syndrome, Ehlers-Danlos syndrome.

Question 9

Hypertensive retinopathy

Answer 9

Findings depend on classification grade of retinopathy.
Focal/generalised arteriolar constriction and straightening.
Arteriosclerosis leading to changes at arteriovenous crossing points: AV nipping or nicking and silver-wiring of retinal arterioles.
Microaneurysms.
Cotton wool spots indicating ischaemia.
Retinal haemorrhages, usually flame shaped.
Exudate, often in macular star pattern.
Arterial macroaneurysms.
Disc oedema.
Tortuous vessels in malignant hypertension.

Question 10

Diabetic retinopathy: pathogenesis

Answer 10

Microangiopathy primarily affecting pre-capillary arterioles, capillaries, and post-capillary venules.
There is loss of pericytes, damage to the vascular endothelial cells, deformation of red blood cells with increased aggregation leading to microvascular occlusion and leakage.

Question 11

Diabetic retinopathy: clinical features

Answer 11

Fundus findings are usually bilateral and broadly symmetrical.
Abnormalities depend on the severity of the disease.
Microaneurysms.
Dot and blot haemorrhages.
Lipid exudates.
Venous beading.
Intraretinal microvascular abnormalities.
Cotton wool spots.
New vessels at the disc or elsewhere.
Tractional retinal detachment.
Macular oedema and thickening (diabetic maculopathy).

Question 12

Glaucoma: overview

Answer 12

Glaucoma is an optic neuropathy associated with raised intraocular pressures leading to irreversible optic nerve damage.
It is usually asymptomatic and is often detected incidentally, but can lead to blindness.

Question 13

Glaucoma: applied physiology

Answer 13

Aqueous humour is produced by the ciliary body and mainly drained through the trabecular meshwork but there is also drainage through uveoscleral routes.
Normal intraocular pressure = 8-21mmHg.

Question 14

Glaucoma: primary angle closure

Answer 14

Narrowing of the anterior chamber drainage angle prevents aqueous fluid outflow resulting in increased intraocular pressure.
Acute: classically a red, painful eye, hazy cornea due to oedema, fixed mid-dilated oval pupil, reduced vision, headache, nausea and vomiting.
Chronic/subacute: may give a history of haloes around lights at night.

Question 15

Glaucoma: primary open angle

Answer 15

Aqueous fluid outflow is reduced despite anterior chamber angle remaining open.
Most common form of glaucoma in patients >50 years.
Risk factors: increased IOP, reduced central corneal thickness, Afro-Caribbean origin, increased age, affects 1st degree relative, hypertension, diabetes, myopia.

Question 16

Glaucoma: secondary glaucoma

Answer 16

Angle may be open or closed but the pathology results from a separate ocular condition or its treatment.

Question 17

Glaucoma: normal tension/pressure glaucoma

Answer 17

Open angle and glaucomatous field loss and disc changes despite and IOP falling within the ‘normal’ range.

Question 18

Glaucoma: conditions leading to secondary glaucoma

Answer 18

Uveitis: trabeculitis (chronic inflammation of the trabecular meshwork resulting in reduced aqueous outflow) or iris bombé (iris adhesions to the anterior capsule of the lens through 360 degrees following anterior uveitis can result in bowing forward of the iris, from trapped aqueous, closing the drainage angle).
Rubeosis: ischaemic insults to the eye (retinal vein/artery occlusions, diabetes) can lead to new blood vessel growth/bleeding in the anterior chamber angle obstructing aqueous flow.
Trauma: damage to the drainage angle from blunt trauma can lead to scarring of the trabecular meshwork.

Question 19

Age-related macular degeneration: overview

Answer 19

AMD is the leading cause of blindness registration in the western world.
There are 2 main types: wet and dry.
The common dry form is associated with gradual visual loss, while the much less common wet or neovascular AMD is associated with rapid and more severe visual loss.

Question 20

Age-related macular degeneration: dry

Answer 20

Progressive atrophic changes of the macula characterised by the presence of drusen, extracellular material deposited between the retinal pigment epithelium and the underlying Bruch’s membrane.
There is resulting loss of the RPE and photoreceptor layers of the retina.

Question 21

Age-related macular degeneration: wet

Answer 21

Accounts for 10% of cases of AMD and is the most common cause of blindness in the Western world.
New vessels grow from the choroidal vasculature and enter the retina forming a choroidal neovascular membrane, which can leak fluid or blood at the macula leading to scarring and visual loss.

Question 22

Age-related macular degeneration: symptoms

Answer 22

Central visual loss (gradual or sudden).
Distortion (metamorphopsia: straight lines look wavy and distorted).
Scotoma.

Question 23

Age-related macular degeneration: signs

Answer 23

Hard drusen (well demarcated yellow lesions).
Soft drusen (ill-defined paler lesions which may become confluent).
Pigmentation.
Subretinal or intraretinal haemorrhage.
Exudate.

Question 24

Age-related macular degeneration: risk factors

Answer 24

Age
Family history
Female sex
Caucasian
Smoking
Hypertension
Cardiovascular disease
Hypercholesterolaemia

Question 25

Cataract: overview

Answer 25

The lens is a biconvex, transparent, avascular structure enclosed by a capsule.
Lens fibres are continually laid down throughout life so the lens is the only eye structure that continues to grow.
With time the lens loses its transparency leading to cataract formation, which is universal with increasing age.

Question 26

Cataract: common symptoms

Answer 26

Gradual deterioration of vision, difficulty reading.

Glare from oncoming car headlights.

Question 27

Cataract: risk factors

Answer 27

Majority are senile.
Diabetes mellitus.
Disorders of calcium homeostasis.
Uveitis.
Intraocular tumours.
Angle closure glaucoma.
Wilson's disease.