1 Workup 1.1 Ophthalmic History Ref: Lecture Notes – Ch2, Oxford Handbook of Ophthalmology Ch1, UpToDate

History of present illness (HPI): □ Chief complaint: → Onset: acute (eg. vascular), subacute (eg. optic neuritis), chronic, acute on chronic (eg. acute glaucoma attack → Laterality: Rt (OD), Lt (OS), both (OU) [NOT ‘LE’] → Quality → Severity → Progression: intermittent vs constant, progressive vs stable → Aggravating and relieving factors □ Associating symptoms: ocular and non-ocular symptoms

Complaint Considerations D/dx Preceding trauma? Eyelid pathologies Pattern of redness? – diffuse vs focal? Perilimbic involvement/sparing? Conjunctivitis (allergic, bacterial, viral) Any pain/discomfort? Subconjunctival haemorrhage □ FB sensation → corneal ds Episcleritis □ Severe pain → keratitis, scleritis, Scleritis Red eye glaucoma Corneal ulcer, abrasion, FB Any photophobia? (corneal ds, uveitis) Keratitis Any blurred/loss of vision? Uveitis Any discharge? (conjunctivitis) Trauma Any associating systemic inflammatory diseases? – eg. SNRA, Behcet’s Acute angle closure glaucoma *: requires urgent ophthalmic referral Any contact lens wear? (keratitis) Transient vs persistent? – vascular Amaurosis fugax due to migraine, insufficiency vs structural causes ↑ICP, retinal a. insufficiency Unilateral vs bilateral vs VF defects? – Ocular media: acute angle closure ocular vs retrobulbar pathologies glaucoma, keratitis, uveitis, vitreous Central vs periphery? – macular vs haemorrhage Acute other pathologies Retinal: RAO, RVO, retinal visual loss Any pain? Red eye? (glaucoma, keratitis, detachment, acute maculopathy 1 endophthalmitis, uveitis, optic neuritis) ON: optic neuritis, AION , Associating symptoms? papilloedema, orbital cellulitis compression □ N/V → acute glaucoma Neuro: pituitary apoplexy, visual □ Neurologic deficit → stroke pathway lesions

1 AION = anterior ischaemic optic neuropathy, which can be caused by GCA or other vascular ds affecting optic disc supply.

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Pattern of visual loss? Ocular media: corneal opacity, chronic glaucoma, cataract, vitreous □ Gradual blurring/dimming haemorrhage □ Distortion → usu maculopathy Retinal: ARMD, macular or retinal Chronic □ Constricting → glaucoma dystrophy, DM retinopathy, DM visual loss □ Central loss → maculopathy macular edema, epiretinal membrane, macular hole Any pain? – dull eye pain in glaucoma Optic pathway: optic neuropathy, Systemic disease? – DM visual pathway lesions Seldom the sole presenting symptoms Trauma Usually useful in differentiating cause of Eyelid: lumps, blepharitis other ocular symptoms Anterior processes: dry eye, Discomfort only? – blepharitis, dry eye, conjunctivitis, anterior uveitis, conjunctivitis a/w discomfort keratitis, corneal ulcers, scleritis Ocular pain Severe pain? – keratitis, corneal ulcer, Acute/chronic glaucoma uveitis, glaucoma, endopthalmitis, Orbital disease: orbital cellulitis, optic scleritis, myositis of EOM neuritis, EOM myositis, dysthyroid eye Pain on eye movement? – optic neuritis disease Periorbital pain? – GCA, migraine, Others: cluster headache, migraine, orbital cellulitis, headache syndromes giant cell arteritis Preceding trauma? Monocular vs binocular? – does diplopia disappear after closing one eye → ocular vs malalignment causes Central: INO, failure to control a Separation of image? – vertical, longstanding squint horizontal or oblique Neurogenic: CN3, 4, 6 palsies Provoking gaze direction? – worst direction represents field of action of NMJ: MG Diplopia paretic muscle (opposite if dysthyroid) Myogenic: dysthyroid eye disease, Intermittent? (myasthenia gravis) myositis, myopathy Any corrective head position? Orbital: fracture, space-occupying lesions (eg. tumours) Worse at distance vs near? (MR palsy in near, LR palsy in distance) Monocular: maculopathies, media opacities, refractive errors Any pain? (orbital, aneurysmal, intracranial mass, inf’n/inf’n, DM) Other neurological features? Any dysthyroid features? Congenital ptosis, eg. levator Onset? – congenital vs acute vs chronic abnormality Bilateral vs unilateral? Apnoneurotic ptosis2 Varies diurnally? – MG CN III palsy Ptosis Associated headache or diplopia? Horner’s syndrome Hx of ocular surgery, trauma? Myasthenia gravis FHx of ptosis? Myogenic – mitochondrial myopathy, myotonic dystrophy, FSHD

2 In aponeurotic ptosis, there is spontaneous disinsertion or dehiscence of levator aponeurosis (tendon connecting levator to tarsal plate). It is the commonest cause of acquired ptosis in adults

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Past ocular history (POH): □ Hx of eye disease, incl refractory error Significance of eye complaints: □ Hx of ocular surgery Red eye (redness ± pain, photophobia, □ Hx of eye trauma discharge) → usually indicates anterior □ Hx of contact lens wearing ocular pathology Painless loss of vision Past medical history (PMH): → usually posterior pathology □ Vascular diseases, eg. HTN, DM, coronary or Glare → usually indicates cataract cerebrovascular disease Distortion (metamorphosia), central □ Systemic inflammatory diseases, eg. sarcoidosis, scotoma → usually macular pathology CTD, Behcet’s disease Flashes (photopsia) and floaters □ Allergic diseases, eg. allergic rhinitis → usually vitreoretinal pathology

Drug Hx □ Current and past medications Medications to be noted in □ Drug allergies ophthalmological patients:

Corticosteroids (a/w glaucoma, Social history: cataract) □ Smoking and alcohol when relevant, eg. vascular event, Hydroxychloroquine unexplained optic neuropathy Amiodarone □ ADL Anti-TB drugs, esp isoniazids

Neuroleptics and anticonvulsants Family history, eg. retinitis pigmentosa (inherited), Neuroptics glaucoma (FHx is a RF)

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1.2 Examination of the Eye Ref: Lecture Notes – Ophthalmology Ch2, Oxford Handbook of Ophthalmology Ch1, IB and JC teaching Basic examination of the eye involves: □ External appearance: eyebrows, eyelids, lacrimal apparatus, obvious ocular abnormalities (eg. squint) □ Visual acuity (VA): distance vs near acuity, aided vs unaided, ± pinhole □ Visual field (VF): confrontation or mid-peripheral vision, Goldman perimeter □ : symmetry, direct and consensual response, accommodation reflex, swinging torch test □ Ocular movement and alignment: EOM test, Hirschberg test, cover and uncover test Additional examination of the eye involves: □ Fluoroscein staining for corneal abrasion and injury □ Slit lamp (biomicroscopy) for anterior segment examination □ Goldmann tonometer for intraocular pressure measurement □ Fundoscopy: disc, retinal vasculature, macula, peripheral

1.2.1 Basic Examination of the Eye A. External Appearance Eyebrows: asymmetry, scarring

Eyelids: □ Lumps, eg. stye3, chalazion4, xanthelasma □ Swelling, eg. blepharitis □ Abnormalities in position → Ptosis: measure distance between upper and lower lids and excursion of upper lid from extreme downgaze to extreme upgaze → Entropion and ectropion: eyelid turning inward and outward respectively □ Eyelash problems, eg. trichiasis (lashes arise from normal position but are posteriorly directed

Lacrimal apparatus: □ Tear film: epiphora (watery eye), dry eye □ Lacrimal swelling: dacryocystitis (lacrimal sac infection)

Other obvious ocular abnormalities, eg. squint

3 Stye (external hordeolum) is an acute eyelash follicular abscess. It is associated with pustule at eyelid margin with erythema, swelling and pain. It is classically due to S. aureus and treatment involves warm compression ± oral Abx. 4 Chalazion refers to chronic inflammation due to obstructed Meibomian (sebaceous) gland. It is initially associated with eyelid swelling and erythema (same as stye) but later becomes a painless, rubbery nodular lesion towards the centre of eyelid. Treatment is again warm compression only

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B. Visual Acuity (VA) Types: □ Unaided vs aided: w/o and w/ spectacles respectively □ Best corrected VA (BCVA): tested w/ trial lenses (gold standard, NOT commonly used) □ Near vs distance: test VA at distance (usu 6m) or near (usu ~30cm) → May be different in myopia and prebysopia Setting and principle: □ Ensure proper illumination □ Use appropriate chart at appropriate distance □ Test each eye in turn and occlude the other using palm of your hand5 or occluder VA expressed as d/D: □ d = distance at which pt is reading chart □ D = distance at which pt is expected to be able to read chart Interpretation: □ Normal = 6/6 (20/20) □ <6/9 (20/30) → use pinhole occluder to correct refractory error □ <6/120 (20/400) → try to determine if pt can → Count fingers (CF) → Hand movement (HM) → Light perception (LP) → No perception of light (NLP) Chart used: □ Snellen’s chart: standard target, placed at 6m (10ft) → Each optotype (letter) subtend 5’ arc and lines subtend 1’ arc → Normal vision = 6/6 (20/20); significant = ≥2 line change □ LogMAR charts, eg. ETDRS chart → MAR = min angle of resolution ≈ 1/Snellen’s quotient (eg. 6/60 = 10) → Equal line/letter spacing and # of optotypes on a row → avoids crowding phenomenon6 → Visual angle doubled every 3 lines → linear ↑difficulty cf Snellen’s □ Other variants, eg. Landolt C, illiterate E test Assessment of VA in children □ ‘Hundreds and thousands’ test for very young children □ Cardiff Acuity test for young children 1-3y □ Sheridan-Gardiner test for older children

5 Fingers should NOT be used (can peek through gaps between fingers). 6 Crowding refers to a phenomenon by which neighboring targets interfere as proximity increases and amblyopic patients are particularly susceptible.

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C. Visual Field (VF) Testing Confrontation: □ Setting: → Pt at one arm length, fixate on your → One eye covered, no spectacles → Object midway between you and pt → Ask patient to focus on your eye □ Coloured pin/moving finger brought into visual field from four quadrants (superotemporal, superonasal, inferotemporal, inferonasal) → ask pt to tell you when object is seen → compare your own VF vs patient’s VF Rapid screening test: more relevant for neurological purposes □ Setting: similar to confrontation □ Process: ask pt to count fingers which you show in each quadrant at mid-peripheral area Perimetry: formal testing for more accurate plotting of visual field □ Can measure kinetic (moving target) vs static visual field □ Goldmann perimetry: manual VF recording using suprathreshold stimuli → detects relative scotomas only □ Humphrey’s perimetry: digital VF recording using threshold stimuli → detects absolute scotomas □ Useful in monitoring subtle changes in VF in chronic ocular and neurological conditions (eg. compression on visual pathway)

Normal VF described as ‘hill of vision’ □ Objects resolved in finest detail at fovea (nasal side) □ VF wider in temporal side than nasal side □ Blind spot (optic n.) at temporal side D. Pupils Size and symmetry: □ Anisocoria = asymmetry of pupillary size → Always reflects efferent defect → Dynamic (neurological cause) vs fixed (mechanical or pharmacological causes) □ In PN disease, pathological pupil is the larger one (mydriatic) → ↑anisocoria in bright light where the normal pupil constricts □ In SN disease, pathological pupil is the smaller one (miotic) → ↑anisocoria in dim light where the normal pupil dilates

Pupillary light reflexes: □ Setting: ALWAYS DIM THE LIGHTS + eye directed to distant object □ Process: use two torches (one for illumination, one for stimulus) to test for → Direct response testing ipsi afferent + ipsi efferent functions → Consensual response testing contra afferent + ipsi efferent functions

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Near reflex: to test afferent + efferent function □ Process: ask pt to look into distance then to a close object □ Components: accommodation, convergence, miosis □ Light-near dissociation: pupils react to near reflex but not to light → Argyll-Robertson pupils: classically a/w midbrain lesions due to neurosyphilis or DM → Adie’s tonic pupil: ciliary ganglionitis leading to denervation of pupillary sphincter and pupillary reinnervation by accommodation fibres originally to ciliary body → Parinaud syndrome: dorsal midbrain lesion due to eg. MS

Swinging torchlight test for relative pupillary afferent defect (RAPD) □ Principle: direct response of one eye compared with consensual response of the same eye → efferent pathway shared but afferent pathways compared □ Setting: dim lighting, eye directed to distant object □ Process: torch directed at each eye in turn and the same pupil is observed → paradoxical dilatation implies RAPD at the eye at which the torch is shining7 □ D/dx: optic nerve lesion (sensitive), very severe retinal diseases (but not /lens opacities) E. Eye Movements Hirschberg (corneal light reflex) test for any squints () □ Torch light held directly ahead (33cm away) with eye in primary position (forward gaze) □ Normal = reflection of light from cornea should be symmetrical □ Squint = reflection from non-fixating eye is displaced □ Pseudosquint = reflection at same position but appear to have squint because of eyelid asymmetry

7 The term reverse RAPD refers to paradoxical dilatation in contralateral eye. It is useful when the pathological eye is dilated with cycloplegic eyedrops for fundal examination.

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Range of eye movements: □ Setting: both eyes open and fixating on finger □ Process: → Ask patient to follow your finger → Move finger in an ‘H’ pattern with finger perpendicular to direction of movement → Press on eyebrows when testing downgaze to stop eyelids from dropping □ Note any: → Diplopia (more sensitive) or malalignment → Limitation of range (ophthalmoplegia) → Nystagmus □ Further testing if there is any diplopia or ophthalmoplegia → Note the direction of max displacement of diplopia → identify pair of ms involved → Cover each eye → the abnormal eye is the one seeing the outer image → Test saccadic movement by asking pt to look at targets held at each side of head → differentiate between restrictive and paralytic causes of ophthalmoplegia - Restrictive: due to ms entrapment, shows sharp mov’t but stops immediately - Paralytic: due to ms weakness, shows weak movement → Ask pt to move eye further beyond limited range → vergence problem (can move beyond) vs duction problem (cannot move beyond) Cover/uncover test for non-paralytic squints □ Principles: → Manifest squint (heterotropia) seen in primary gaze - Affects one eye only with the other used as fixation → Latent squint (heterophoria) NOT seen in primary gaze - Only seen when binocular fusion is interrupted - Refers to tendency of visual pathways to drift apart but usually corrected by unconscious effort, i.e. reflects a disparity rather than affect a specific eye □ Cover test: one eye occluded by occluder → Look at the contralateral eye → Contralateral tropia → corrective drift to neutral position, i.e. inward in , outward in → Ipsi tropia or phoria → no movement □ Uncover test: occluder removed from the eye → Look at the ipsilateral eye → Contralateral tropia → corrective drift to neutral position → Phoria → corrective drift to neutral position → Alternating tropia with preference of fixation (i.e. bilateral heterotropia but one eye usu used to fixate) → unoccluded eye remains fixated □ Alternating cover-uncover test → Occluder moved from one eye to another rapidly □ Prism cover test: prisms used to correct gaze direction → prism that eliminates squint response in cover test used to measure degree of squint

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1.2.2 Additional Examination of the Eye Diagnostic use of fluorescein: □ Principle: fluorescein absorbs blue light and emits green fluorescence □ Examination of corneal abrasion/ulcers → A weak, highly fluorescent solution of dye applied to the eye → Eye examined with a blue light → any corneal abrasion fluoresces bright green □ Examination of corneal breaks leading to aqueous leaks → A drop of highly concentrated (2%) fluorescein solution (not fluorescent) applied to eye → Eye examined with blue light → any aqueous leakage would dilute dye to fluorescent concentration → bright green at junction w/ dark concentrated fluorescein

Slit lamp for examination of lids and anterior segment □ Principle: → Biomicrosope for magnified stereoscopic view → Slit of light directed to highlight a cross-section of transparent media of eye to be examined □ : any injection and distribution? Any discharge? Any subconjunctival haemorrhage? □ Cornea: clarity? Any opacity or defects? Any oedema? □ Anterior chamber: Is it intact? Any hypopyon or hyphaema? Any keratic precipitates? Any cells and flare? □ /pupils: Is shape of pupil normal? □ Lens: Any opacities/clouding?

Goldmann tonometer for measurement of IOP □ Principle: → Plastic cylinder pressed against anaesthetized cornea → Ring of flattening of cornea made visible by fluorescein in the tear film → Horizontally disposed prism within cylinder splits ring of contact into two semicircles → Pressure of cylinder adjusted such that the two semicircles just interlocks (end-points) → Ocular pressure = force applied by cylinder □ Use: to test for ↑IOP in glaucoma □ Other variants: → Non-contact devices using puffs of air → Hand-held US pachymeters to measure corneal thickness to correct IOP measurements

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Ophthalmoscopy (fundoscopy) for examination of retina □ Types: direct ophthalmoscopy (for non-specialists, only visualizes 10% of retina), indirect ophthalmoscopy, special lenses in slit lamp (for ophthalmologists only) □ Setting: → Lights dimmed, pt looks straight ahead at distance → Patient’s pupil first dilated with 1% tropicamide (cycloplegic), 2.5% phenylephrine (mydriatic) or Mydrin-P (combination eyedrop) → Examiner’s Rt eye used to examine pt’s Rt eye etc → Index finger used to switch between lenses □ Adjustments: → Lenses to adjust magnification power (X-clockwise → +ve diopters) → Rheostat to adjust brightness of light source → Apertures: usually use large aperture - Small → small pupils - Red-free filter → optic disc pallor, minute vessel Δs - Slit → for anterior eye or elevated lesions - Grid → for estimation of size of fundal lesions □ Process: → First view the red reflex through pupil at a distance of about ~30cm from eye - Corneal and lens opacities appear as dark silhouettes against red reflex - Can be further visualized by turning the ophthalmoscope to the hypermetropic side (i.e. +ve, green/black dioptres) → Follow the red reflex and approach the eye to within a few cm → re-focus by adjusting to myopic side (i.e. –ve, red dioptres) until retina clearly visualized → Go closer for a wider view (usu only visualize 10% of retina) □ Examine the following → Optic disc: approach at 15o temporal to gaze line - Colour: pale in optic atrophy (temporal pallor in MS) - Contour: blurred margins in papilloedema OR papillitis - Cup-to-disc ratio: increased (>0.4) in glaucoma - Disc vessels: neovascularization in proliferative DMR → Retinal vasculature: - Arteries: bright red, thinner, reflects light (due to sm content) - Veins: darker red, larger caliber - HTN retinopathy: AV nipping, silver/copper wiring → Macula: central part of retina bound by sup. and inf. retinal vv. - Foveal reflex: in youth, foveal pit appears at bright pinpoint of light in centre of retina - Abnormal lesions, eg. haemorrhage, exudates, CWSs → Retina: systematically in a 360o sweep - Look for exudates, haemorrhages, colour changes and other lesions

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Fundoscopic gallery: disc-centred vs macula-centred photo □ Exudates: → Soft exudate (cotton wool spots, CWS) with blurred margins - Due to microinfarcts of axons - Seen in microangiopathic ds, eg. DM, HTN → Hard exudate with well-defined margins - Due to lipoprotein leakage from vessels - Seen in ↑capillary permeability, eg. DMR □ Haemorrhages: → Flame-shaped haemorrhage: - Due to blood accumulating at nerve fibre layer - Seen in ↑capillary pressure, eg. HTN, RVO, papilloedema, bleeding disorder → Dot-and-blot haemorrhage (microaneurysms): - Due to impaired vascular autoregulation ± rupture - Specific for diabetic retinopathy → Subhyaloid haemorrhage: - Due to blood between vitreous and retina - Specific for subarachnoid haemorrhage → Vitreous haemorrhage: - Due to bleeding into vitreous humour

□ Vascular changes: → Central retinal artery obstruction (CRAO): - Pan-retinal pallor with cherry red spot at fovea - Due to ↓perfusion of retina with macular sparing (derives blood supply from choroid) → Branch of retinal artery obstruction (BRAO): - Partial retinal pallor with partial cherry red spot → Central retina vein obstruction (CRVO): - ‘Blood and thunder’ appearance with disc swelling, diffuse flame haemorrhage and CWSs

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□ Other retinal lesions: → Laser photocoagulation scars for DM retinopathy → Retinal detachment with elevated sheet of retinal tissues with fold - Look for corresponding VF defect (opposite to site of lesion) → Retinitis pigmentosa: dark deposits of irregular clumps of pigments □ Disc lesions: → Disc pallor in optic atrophy → Blurred disc margin in - Papilloedema: bilateral, a/w diffuse flame-shaped haemorrhage, visual loss if any usually only transient, S/S of ↑ICP - Papillitis: may be unilateral, no flame-shaped haemorrhage, visual loss more prominent due to optic neuritis □ Common disease associations: → Diabetic retinopathy: - Retinal microangiopathy → microaneurysm, dot-and-blot haemorrhage - Retinal ischaemia → cotton wool spots, venous beading, intra-retinal microvascular abnormalities (IRMA) - Breakdown of blood-retinal barrier → hard exudates, macular oedema - Vasoproliferation → neovascularization → vitreous haemorrhage, tractional retinal detachment, rubeosis iridis ± acute rubeotic glaucoma → Hypertensive retinopathy: - Grade I = silver wiring - Grade II = G1 + arteriovenous nipping - Grade III = G2 + flame-shaped haemorrhage and CWS - Grade IV = G3 + papilloedema

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