Ophthalmology

Question 1

aetiology of acute angle-closure glaucoma

Answer 1

optic neuropathy due to raised IOP

RFs (impairment to aqueous outflow)
- hypermetropia (long sightedness)
- pupillary dilatation
- lens growth associated w age

Question 2

px of acute angle-closure glaucoma

Answer 2

• haloes around lights
• semi-dilated non-reacting pupils
• severe pain
• worse with mydriasis
• hard, red eye
• corneal oedema -> dull or hazy cornea
• decreased visual acuity

Question 3

acute angle-closure glaucoma ix & mx

Answer 3

ix
- tonometry to check for elevated IOP
- gonioscopy - slit lamp lens which allows for visualisation of the angle

Mx
- urgent opthal referral

initial:
- combination eye drops (direct parasympathomimetic- pilocarpine, beta blocker- timolol, alpha-2 agonist- apraclonidine)
- IV acetazolamide

definitive mx
- laser peripheral iridotomy
(tiny holes in peripheral iris)

Question 4

Age-related macular degeneration aetiology

Answer 4

Degeneration of the central retina (macula)

degeneration of retinal photoreceptors that results in the formation of drusen

Drusen may become confluent in late disease to form a macular scar

most common cause of blindness in the UK

Question 5

ARMD RFs

Answer 5

advancing age (!!)
smoking
family hx
cvd rfs

Question 6

dry macular degeneration features (ARMD)

Answer 6

a.k.a atrophic / early ARMD
90% of cases
drusen -> yellow round spots in Bruch’s membrane
Gradual reduction in visual acuity
alteration to retinal pigment epithelium (RPE)

Question 7

wet macular degeneration features (ARMD)

Answer 7

a.k.a exudative / neovascular/ late ARMD
Choroidal neovascularisation
Leakage of serum fluid & blood
10 % of cases
worst prognosis
subacute reduction in visual acuity

Question 8

ARMD px

Answer 8

Reduction in visual acuity, esp near field objects
Difficulties in dark adaption
Poor night vision
Daily visual fluctuations
Photopsia (flickering/ flashing) lights
Glare around objects
Charles-Bonnet syndrome - visual hallucinations

Question 9

ARMD ix

Answer 9

Amsler grid testing -> distortion of line perception

Fundoscopy/ Slit lamp microscopy -> drusen (yellow pigment deposition in macula), pigmentary, exudative or haemorrhagic changes of retina

if neovascular ARMD: Fluorescein angiography -> to guide anti-VEGF therapy. Add indocyanine green angiography to visualise choroidal circulation changes.

Optical coherence tomography -> 3D retinal visualisations to reveal areas of disease which aren’t visible using microscopy alone

Question 10

ARMD tx

Answer 10

Dry
- combination of zinc with anti-oxidant vitamins A,C and E

Wet
- vascular endothelial growth factor (VEGF)
— e.g. ranibizumab, bevacizumab and pegaptanib
— 4 weekly injection, start w/in first 2 months
- laser photocoagulation (complication: acute visual loss)

Question 11

Allergic conjunctivitis tx

Answer 11

(usually seen in context of hay fever)

first-line: topical or systemic antihistamines
second-line: topical mast-cell stabilisers, e.g. Sodium cromoglicate and nedocromil

Question 12

Anterior uveitis associations

Answer 12

HLA-B27
Ankylosing spondylitis
reactive arthritis
Ulcerative colitis
Crohn’s disease
Behcet’s disease
Sarcoidosis: bilateral disease may be seen

Question 13

Anterior uveitis mx

Answer 13

urgent review by ophthalmology

cycloplegics (dilates the pupil which helps to relieve pain and photophobia) e.g. Atropine, cyclopentolate

steroid eye drops

Question 14

Argyll-Robertson pupil px & aetiology

Answer 14

small, irregular pupils
no response to light but there is a response to accommodate

Causes
- diabetes mellitus
- syphilis

mnemonics
- Argyll-Robertson Pupil (ARP) is Accommodation Reflex Present (ARP) but Pupillary Reflex Absent (PRA)
- prostitutes accommodate, but don’t react

Question 15

Blepharitis aetiology

Answer 15

Inflammation of the eyelid margins -> dry eyes -> grittiness, esp at eyelid margins (usually bilateral)

meibomian gland dysfunction (common, posterior blepharitis)
OR seborrhoeic dermatitis/staphylococcal infection (less common, anterior blepharitis)

associated w rosacea

Question 16

Blepheritis tx

Answer 16

hot compresses BD - softening of the lid margin

‘lid hygiene’, mechanical removal of the debris
- cotton wool buds in cooled boiled water, baby shampoo, sodium bicarbonate

artificial tears for dry eyes

Question 17

assessment & mx of blurred vision

Answer 17

visual acuity with a Snellen chart
- pinhole occluders to check if refractive error is cause

visual fields

fundoscopy

Mx
- refractive error -> optician review
- other -> opthalmology (urgent if pain or visual loss)

Question 18

cataracts RFs

Answer 18

Ageing (!!)
Smoking
Increased alcohol
Trauma
Diabetes mellitus
Long-term corticosteroids
Radiation exposure
Myotonic dystrophy
Hypocalcaemia

Question 19

Defect in the red reflex & Faded colour vision in which condition??

Answer 19

Cataracts

Question 20

Cataracts Ix

Answer 20

Ophthalmoscopy: done after pupil dilation. Findings: normal fundus and optic nerve

Slit-lamp examination. Findings: visible cataract

Question 21

cataract classification

Answer 21

Nuclear: change lens refractive index, common in old age

Polar: localized, commonly inherited, lie in the visual axis

Subcapsular: due to steroid use, just deep to the lens capsule, in the visual axis

Dot opacities: common in normal lenses, also seen in diabetes and myotonic dystrophy

Question 22

Cataract mx

Answer 22

Non-surgical conservative mx initially - stronger glasses/contact lens, or use brighter lighting

Surgical - removing the cloudy lens and replacing this with an artificial one

referral for surgery should be dependent upon whether a visual impairment is present, impact on quality of life, and patient choice !!

Question 23

cataract surgery complications

Answer 23

Posterior capsule opacification: thickening of the lens capsule

Retinal detachment

Posterior capsule rupture

Endophthalmitis: inflammation of aqueous and/or vitreous humour

Question 24

Central retinal artery occlusion causes

Answer 24

thromboembolism (from atherosclerosis) or arteritis (e.g. temporal arteritis)

Question 25

features of Central retinal artery occlusion

Answer 25

sudden, painless unilateral visual loss relative afferent pupillary defect 'cherry red' spot on a pale retina

Question 26

Central retinal vein occlusion (CRVO) px

Answer 26

sudden, painless reduction or loss of visual acuity, usually unilaterally fundoscopy - widespread hyperaemia - severe retinal haemorrhages:'stormy sunset'

Question 26

Central retinal vein occlusion (CRVO) mx

Answer 26

conservatively indications for treatment in patients with CRVO include: - macular oedema - intravitreal anti-vascular endothelial growth factor (VEGF) agents - retinal neovascularization - laser photocoagulation

Question 27

corneal foreign body indications for referral to ophthalmology

Answer 27

Suspected penetrating eye injury due to high-velocity injuries (e.g. drilling, lawn moving or hammering) or sharp objects (e.g. as glass, knives, pencils or thorns) Significant orbital or peri-ocular trauma has occurred. A chemical injury has occurred (irrigate for 20-30 mins before referring) Foreign bodies composed of organic material (such as seeds, soil) -higher risk of infection and complications Foreign bodies in or near the centre of the cornea Any red flags e.g. severe pain; irregular, dilated or non-reactive pupils; significant reduction in visual acuity.

Question 28

Corneal ulcer aetiology

Answer 28

RFs - contact lens use - vitamin A deficiency: a particular problem in the developing world causes - bacterial keratitis - fungal keratitis - viral keratitis: herpes simplex, herpes zoster - may lead to a dendritic ulcer - Acanthamoeba keratitis: associated with contact lens use

Question 29

non-proliferative diabetic retinopathy diabetic retinopathy features depending on classification

Answer 29

Mild NPDR - 1 or more microaneurysm Moderate NPDR - microaneurysms - blot haemorrhages - hard exudates - cotton wool spots ('soft exudates' - represent areas of retinal infarction) - venous beading/looping - intraretinal microvascular abnormalities (IRMA) less severe than in severe NPDR Severe NPDR - blot haemorrhages and microaneurysms in 4 quadrants - venous beading in at least 2 quadrants - IRMA in at least 1 quadrant

Question 30

proliferative diabetic retinopathy features

Answer 30

Retinal neovascularisation - may lead to vitrous haemorrhage fibrous tissue forming anterior to retinal disc more common in Type I DM, 50% blind in 5 years

Question 31

Maculopathy (diabetic retinopathy) features

Answer 31

based on location rather than severity, anything is potentially serious hard exudates and other 'background' changes on macula check visual acuity more common in Type II DM

Question 32

diabetic retinopathy mx

Answer 32

All patients - optimise glycaemic control, blood pressure and hyperlipidemia - regular review by ophthalmology Maculopathy - if visual acuity affected -> intravitreal vascular endothelial growth factor (VEGF) inhibitors Non-proliferative retinopathy - regular observation - if severe/very severe consider panretinal laser photocoagulation Proliferative retinopathy - panretinal laser photocoagulation - intravitreal VEGF inhibitors. e.g. ranibizumab - if severe or vitreous haemorrhage: vitreoretinal surgery

Question 33

complications of pan retinal laser photocoagulation

Answer 33

- following treatment around 50% of patients develop a noticeable reduction in their visual fields due to the scarring of peripheral retinal tissue - decrease in night vision (rods are predominantly responsible for vision in low light conditions, the majority of rod cells are located in the peripheral retina) - a generalised decrease in visual acuity - macular oedema

Question 34

what medication can differentiate between episcleritis and scleritis?

Answer 34

phenylephrine drops phenylephrine blanches the conjunctival and episcleral vessels but not the scleral vessels if the eye redness improves after phenylephrine a diagnosis of episcleritis can be made

Question 35

Episcleritis causes & mx

Answer 35

idiopathic inflammatory bowel disease rheumatoid arthritis Management - conservative - artificial tears may sometimes be used

Question 36

types of stye (infection of the glands of the eyelids) & mx

Answer 36

- external (hordeolum externum): infection (usually staphylococcal) of the glands of Zeis (sebum producing) or glands of Moll (sweat glands). - internal (hordeolum internum): infection of the Meibomian glands. May leave a residual chalazion (Meibomian cyst) -management includes hot compresses and analgesia. CKS only recommend topical antibiotics if there is an associated conjunctivitis

Question 37

Herpes simplex keratitis mx

Answer 37

(most commonly presents with a dendritic corneal ulcer) immediate referral to an ophthalmologist topical aciclovir

Question 38

Herpes zoster ophthalmicus mx

Answer 38

oral antiviral treatment for 7-10 days - start w/in 72hrs - iv for very severe infection or if immunocompromised topical corticosteroids may be used to treat any secondary inflammation of the eye ocular involvement requires urgent ophthalmology review

Question 39

Holmes-Adie pupil px

Answer 39

- unilateral in 80% of cases - dilated pupil - once the pupil has constricted it remains small for an abnormally long time - slowly reactive to accommodation but very poorly (if at all) to light Holmes-Adie syndrome - Holmes-Adie pupil with absent ankle/knee reflexes

Question 40

Horner syndrome px

Answer 40

- miosis (small pupil) - ptosis - enophthalmos (sunken eye) anhidrosis (loss of sweating one side - depends on location of lesion) - pupillary dilation with apraclonidine drops* (*an alpha-adrenergic agonist causes mild pupillary constriction in the normal pupil by down-regulating the norepinephrine release at the synaptic cleft)

Question 41

Horner syndrome - central lesion px & causes

Answer 41

Anhidrosis of the face, arm and trunk Stroke Syringomyelia Multiple sclerosis Tumour Encephalitis

Question 42

Horner syndrome - pre-ganglionic lesion px & causes

Answer 42

Anhidrosis of the face Pancoast's tumour Thyroidectomy Trauma Cervical rib

Question 43

Horner syndrome - post-ganglionic lesion px & causes

Answer 43

No anhidrosis Carotid artery dissection Carotid aneurysm Cavernous sinus thrombosis Cluster headache

Question 44

hypertensive retinopathy classification (Keith-Wagener classification)

Answer 44

1. Arteriolar narrowing and tortuosity Increased light reflex - silver wiring 2. Arteriovenous nipping 3. Cotton-wool exudates Flame and blot haemorrhages These may collect around the fovea resulting in a 'macular star' 4. Papilloedema

Question 45

Infective conjunctivitis mx

Answer 45

- normally self limiting in 1-2 wks - topical antibiotic therapy (Chloramphenicol: drops are given 2-3 hourly or ointment qds) - topical fusidic acid BD is alternative (in pregnancy) - advice should be given not to share towels - school exclusion is not necessary contact lens users - topical fluoresceins to identify any corneal staining - do not wear until it resolves - tx as above

Question 46

causes of keratitis

Answer 46

(red eye w pain, photophobia, gritty sensation, maybe hypopyon) bacterial - Staphylococcus aureus - Pseudomonas aeruginosa is seen in contact lens wearers fungal amoebic - acanthamoebic keratitis - increased incidence if eye exposure to soil or contaminated water - pain is classically out of proportion to the findings parasitic: - onchocercal keratitis ('river blindness') viral - herpes simplex keratitis environmental

Question 47

keratitis mx

Answer 47

contact lens wearers w painful red eye - same-day referral to an eye specialist for slit lamp to rule out microbial keratitis stop using contact lens until the symptoms have fully resolved topical antibiotics - typically quinolones are used first-line cycloplegic for pain relief e.g. cyclopentolate

Question 48

Causes of mydriasis (large pupil)

Answer 48

Third nerve palsy Holmes-Adie pupil Traumatic iridoplegia Phaeochromocytoma Congenital

Question 49

Drugs which cause mydriasis

Answer 49

topical mydriatics: tropicamide, atropine sympathomimetic drugs: amphetamines, cocaine anticholinergic drugs: tricyclic antidepressants

Question 50

nasolacrimal duct obstruction mx

Answer 50

- teach parents to massage the lacrimal duct - usually resolves in 1 yr - if not, opthal referral for probing

Question 51

why is hyphema dangerous?

Answer 51

Hyphema = blood in the anterior chamber of the eye main risk to sight comes from raised intraocular pressure due to the blockage of the angle and trabecular meshwork with erythrocytes

Question 52

ocular trauma & hyphema mx

Answer 52

Strict bed rest - excessive movement can redisperse blood that had previously settled high-risk cases are often admitted otherwise daily ophthalmic review and pressure checks initially as an outpatient. assess for orbital compartment syndrome (e.g. secondary to retrobulbar haemorrhage) -> true ophthalmic emergency

Question 53

optic neuritis causes

Answer 53

multiple sclerosis: the commonest associated disease diabetes syphilis

Question 54

optic neuritis features & mx

Answer 54

- acute unilateral decreased visual acuity - hrs or days - poor discrimination of colours (red desaturation) - pain worse on eye movement - RAPD - central scotoma ix MRI of the brain and orbits with gadolinium contrast mx high-dose steroids recovery usually in 4-6 weeks

Question 55

Preorbital vs orbital cellulitis

Answer 55

Periorbital (preseptal) cellulitis - infection anterior to the orbital septum Orbital cellulitis - infection of fat and muscles posterior to the orbital septum, within the orbit but not involving the globe reduced visual acuity, proptosis, ophthalmoplegia/pain with eye movements, restricted movements, chemosis, RAPD = orbital

Question 56

causes of papiloedema

Answer 56

increased intracranial pressure - space-occupying lesion: neoplastic, vascular - malignant hypertension - idiopathic intracranial hypertension - hydrocephalus - hypercapnia rare other causes - hypoparathyroidism and hypocalcaemia - vitamin A toxicity

Question 57

vitreous detachment ix & mx

Answer 57

RF - age - highly myopic (near-sighted) ix - Weiss ring on ophthalmoscopy (the detachment of the vitreous membrane around the optic nerve to form a ring-shaped floater). - examined by an ophthalmologist within 24hrs to rule out retinal tears or detachment. mx - nothing - gradually improve over a period of around 6 months - if retinal tear/ detachment -> surgery

Question 58

orbital cellulitis ix & mx

Answer 58

CT contrast of orbit & blood culture medical emergency -> hospital admission for IV antibiotics, urgent senior review

Question 59

orbital cellulitis causes & RFs

Answer 59

- Most common bacterial causes – Streptococcus, Staphylococcus aureus, Haemophilus influenzae B. Risk factors - Childhood - Mean age of hospitalisation 7-12 years - Previous sinus infection - Lack of Hib vaccination - Recent eyelid infection/ insect bite on eyelid (periorbital cellulitis) - Ear or facial infection

Question 60

preseptal cellulitis mx

Answer 60

All cases should be referred to secondary care for assessment Oral antibiotics are frequently sufficient - usually co-amoxiclav contrast CT of orbit if suspecting orbital cellulitis

Question 61

night blindness and tunnel vision?

Answer 61

Retinitis pigmentosa fundoscopy: black bone spicule-shaped pigmentation in the peripheral retina, mottling of the retinal pigment epithelium

Question 62

Ocular manifestations of rheumatoid arthritis?

Answer 62

25% of patients having eye problems Ocular manifestations keratoconjunctivitis sicca (most common) episcleritis (erythema) scleritis (erythema and pain) corneal ulceration keratitis Iatrogenic steroid-induced cataracts chloroquine retinopathy

Question 63

primary open-angle glaucoma mx

Answer 63

1. offer 360° selective laser trabeculoplasty (SLT) first-line to people with an IOP of ≥ 24 mmHg 2.prostaglandin analogue (PGA) eyedrops 3. beta-blocker eye drops / carbonic anhydrase inhibitor eye drops / sympathomimetic eye drops 4. surgery in the form of a trabeculectomy may be considered in refractory cases

Question 64

Prostaglandin analogues example MoA in eye Advese effects

Answer 64

latanoprost Increases uveoscleral outflow OD eye drops Adverse effects include brown pigmentation of the iris, increased eyelash length

Question 65

Beta-blocker eye drops example MoA in eye CI

Answer 65

(e.g. timolol, betaxolol) Reduces aqueous production Should be avoided in asthmatics and patients with heart block

Question 66

Sympathomimetics eye drops example MoA in eye CI

Answer 66

(e.g. brimonidine, an alpha2-adrenoceptor agonist) Reduces aqueous production and increases outflow Avoid if taking MAOI or tricyclic antidepressants Adverse effects include hyperaemia

Question 67

Carbonic anhydrase inhibitors

Answer 67

(e.g. Dorzolamide) Reduces aqueous production Systemic absorption may cause sulphonamide-like reactions

Question 68

Miotics (e.g. pilocarpine, a muscarinic receptor agonist)

Answer 68

Increases uveoscleral outflow Adverse effects included a constricted pupil, headache and blurred vision

Question 69

peripheral visual field loss- nasal scotoma -> tunnel vision decreased visual acuity optic disc cupping what is this?

Answer 69

primary open-angle glaucoma (POAG)

Question 70

Fundoscopy signs of primary open-angle glaucoma

Answer 70

1. Optic disc cupping - cup-to-disc ratio >0.7 (normal = 0.4-0.7), occurs as loss of disc substance makes optic cup widen and deepen 2. Optic disc pallor - indicating optic atrophy 3. Bayonetting of vessels - vessels have breaks as they disappear into the deep cup and re-appear at the base 4. Additional features - Cup notching (usually inferior where vessels enter disc), Disc haemorrhages

Question 71

Marcus-Gunn pupil?

Answer 71

a.k.a relative afferent pupillary defect - found by swinging light test - caused by a lesion anterior to the optic chiasm-> retina: detachment or optic nerve: optic neuritis e.g. multiple sclerosis finding: the affected and normal eye appears to dilate when light is shone on the affected

Question 72

Pathway of pupillary light reflex

Answer 72

afferent: retina → optic nerve → lateral geniculate body → midbrain efferent: Edinger-Westphal nucleus (midbrain) → oculomotor nerve

Question 73

Retinal detachment aetiology & RFs?

Answer 73

neurosensory tissue that lines the back of the eye comes away from its underlying pigment epithelium reversible cause of visual loss, provided it is recognised and treated before the macula is affected, otherwise permanent visual loss RFs - diabetes mellitus - myopia - age - previous cataract surgery - eye trauma

Question 74

pt seeing flashes & floaters. what now?

Answer 74

most likely just posterior vitreous detachment But refer urgently (<24 hours) to an ophthalmologist for assessment with a slit lamp and indirect ophthalmoscopy for pigment cells and vitreous haemorrhage retinal detachment - also have dense shadow that starts peripherally progresses towards the central vision, central visual loss, straight lines -> curved

Question 75

Scleritis RFs

Answer 75

rheumatoid arthritis: the most commonly associated condition systemic lupus erythematosus sarcoidosis granulomatosis with polyangiitis

Question 76

scleritis mx

Answer 76

same-day assessment by an ophthalmologist oral NSAIDs first-line oral glucocorticoids for more severe presentations immunosuppressive drugs for resistant cases (and also to treat any underlying associated diseases)

Question 77

Squints types

Answer 77

concomitant (common) - Due to imbalance in extraocular muscles Convergent is more common than divergent paralytic (rare) - Due to paralysis of extraocular muscles

Question 78

squint ix & mx

Answer 78

important to detect as uncorrected -> amblyopia (the brain fails to fully process inputs from one eye and over time favours the other eye) ix - corneal light reflection test - holding a light source 30cm from face to see if the light reflects symmetrically on the pupils - cover test - focus on object, cover one eye, observe movement of other eye mx - referral to secondary care - eye patches may help prevent amblyopia

Question 79

most common causes of a sudden painless loss of vision

Answer 79

- ischaemic/vascular a.k.a amaurosis fugax e.g. thrombosis (CRVO, CRAO), embolism, temporal arteritis, TIA, ischaemic optic neuropathy - vitreous haemorrhage - retinal detachment - retinal migraine

Question 80

Causes of tunnel vision

Answer 80

papilloedema glaucoma retinitis pigmentosa choroidoretinitis optic atrophy secondary to tabes dorsalis hysteria

Question 81

Common causes of vitreous haemorrhage

Answer 81

proliferative diabetic retinopathy (over 50%) posterior vitreous detachment ocular trauma: the most common cause in children and young adults