📋 Key Information Summary
- Visual failure is classified as acute (sudden) or chronic (gradual); the distinction drives urgency of assessment and differential diagnosis.
- Acute painless visual loss is an ophthalmological emergency — think retinal artery/vein occlusion, retinal detachment, vitreous haemorrhage, and ischaemic optic neuropathy until proven otherwise.
- Acute painful visual loss raises concern for acute angle-closure glaucoma, optic neuritis, anterior uveitis, and endophthalmitis.
- Cataracts remain the leading cause of reversible blindness worldwide and the most common indication for elective surgery in Australia (phacoemulsification under MBS).
- Primary open-angle glaucoma (POAG) affects ~3% of Australians over 50; it is insidious, often asymptomatic until advanced, and requires lifelong monitoring with intraocular pressure (IOP), optic disc assessment, and visual fields.
- Age-related macular degeneration (AMD) is the leading cause of legal blindness in Australia; wet AMD is treated with intravitreal anti-VEGF injections (ranibizumab, aflibercept) under PBS authority.
- Optic neuritis typically presents with painful visual loss in young adults and warrants MRI to evaluate for demyelinating disease (multiple sclerosis).
- Giant cell arteritis (GCA) must be considered in any patient >50 years with sudden visual loss, jaw claudication, or scalp tenderness — immediate high-dose corticosteroids are sight-saving.
- Refractive errors (myopia, hyperopia, astigmatism, presbyopia) are the most common correctable causes of blurred vision across all age groups.
- Amblyopia is the most common cause of unilateral visual impairment in children and is reversible if treated before age 7–8 years.
- Diabetic retinopathy screening (dilated fundoscopy or retinal photography) is recommended annually for all people with diabetes and is funded through MBS item 12325.
- Aboriginal and Torres Strait Islander Australians experience 3 times the rate of blindness compared with non-Indigenous Australians; trachoma persists in remote communities, and diabetic retinopathy is disproportionately prevalent.
- Low-vision rehabilitation and timely referral to Vision Australia or state-based services should be offered to all patients with irreversible visual impairment.
Introduction & Australian Epidemiology
Visual failure encompasses any reduction in visual acuity, visual field, colour vision, or contrast sensitivity that impairs a patient's functional vision. It may present as unilateral or bilateral, acute or chronic, painful or painless, and can affect any age group. A systematic diagnostic approach is essential because the differential diagnosis is broad — ranging from benign refractive error to life-threatening conditions such as giant cell arteritis or intracranial neoplasm.
In Australia, vision disorders affect approximately 13 million people to some degree, and an estimated 453,000 Australians are blind or vision-impaired (AIHW, 2023). The leading causes of visual impairment in adults are:
- Uncorrected refractive error — ~55% of all visual impairment nationally
- Cataracts — the most common cause of bilateral severe visual loss in older Australians; ~250,000 cataract extractions are performed annually
- Age-related macular degeneration — responsible for ~50% of legal blindness registrations
- Glaucoma — affects ~300,000 Australians, with half undiagnosed
- Diabetic retinopathy — the leading cause of preventable blindness in working-age Australians
In children, the most common causes of visual impairment are amblyopia, congenital cataracts, retinopathy of prematurity, and optic nerve disorders. Aboriginal and Torres Strait Islander Australians bear a disproportionate burden, with rates of blindness approximately three times those of non-Indigenous Australians (AIHW Eye Health Report, 2022).
Red-flag mnemonic — "EYES": Emergency (sudden loss), Young child (retinoblastoma, amblyopia, congenital cataract), Elderly (GCA, ischaemic optic neuropathy), Systemic disease (diabetes, hypertension, autoimmune). Any new visual symptom with these features warrants same-day ophthalmological assessment.
Visual Failure Diagnostic Approach
History — Key Questions
| Domain | Questions | Diagnostic Significance |
|---|---|---|
| Onset | Sudden vs gradual? Over hours, days, months? | Sudden → vascular, neurological emergency; gradual → refractive, cataract, glaucoma |
| Pain | Present? Aching, sharp, on eye movement? | Pain + vision loss → angle-closure glaucoma, optic neuritis, uveitis, scleritis |
| Laterality | Unilateral vs bilateral? | Unilateral → local eye pathology or ipsilateral vascular; bilateral → refractive, toxic, neurological (chiasmal) |
| Associated symptoms | Flashes, floaters, curtain, halos, headache, jaw claudication? | Flashes/floaters/curtain → retinal detachment; halos → angle closure; jaw claudication → GCA |
| Risk factors | Diabetes, hypertension, family history, smoking, steroids, trauma? | Diabetes → retinopathy; family history → glaucoma; steroids → cataract/glaucoma |
| Medications | Ethambutol, chloroquine/hydroxychloroquine, amiodarone, tamoxifen, corticosteroids? | Toxic optic neuropathy, corneal deposits, drug-induced cataract or glaucoma |
Bedside Examination in Primary Care
1
Visual Acuity
Snellen chart at 6 m (or Snellen equivalent on a phone/app at 40 cm if wall chart unavailable). Test each eye separately with current correction. Document pinhole acuity — improvement with pinhole suggests refractive error.
2
Pupillary Reflexes
Check for relative afferent pupillary defect (RAPD / Marcus Gunn pupil) using the swinging torch test. RAPD indicates optic nerve or severe retinal pathology on the affected side.
3
Visual Fields
Confrontation testing — compare each eye to your own. Assess all four quadrants. Detect hemianopia (stroke/chiasmal lesion), arcuate defect (glaucoma), or central scotoma (macular/optic neuritis).
4
Eye Movements
Assess all six cardinal directions of gaze. Diplopia with restricted movement suggests cranial nerve palsy (III, IV, VI) or orbital pathology.
5
Anterior Segment
Inspect with penlight — corneal clarity, anterior chamber depth (shallow = angle-closure risk), pupil size/symmetry, lens opacity, redness. Measure IOP if tonometry available.
6
Fundoscopy
Dilated fundoscopy (tropicamide 1% ± phenylephrine 2.5%) when safe. Assess disc (cupping, pallor, swelling), macula, vessels, and retina. Consider fundus photography or teleophthalmology referral.
Classification by Onset and Laterality
Emergent causes of visual failure (require same-day ophthalmology assessment): Retinal artery occlusion (60-minute window for intervention), retinal detachment, acute angle-closure glaucoma, giant cell arteritis, chemical injury, endophthalmitis, and orbital compartment syndrome.
| Pattern | Common Causes | Urgency |
|---|---|---|
| Acute unilateral, painless | Retinal artery/vein occlusion, retinal detachment, vitreous haemorrhage, ischaemic optic neuropathy (arteritic or non-arteritic) | Emergency |
| Acute unilateral, painful | Acute angle-closure glaucoma, optic neuritis, anterior uveitis, keratitis, endophthalmitis | Emergency |
| Acute bilateral | Bilateral occipital infarction, toxic optic neuropathy (methanol), cortical blindness, severe bilateral uveitis | Emergency |
| Chronic unilateral | Cataract, chronic glaucoma, amblyopia, chronic retinal detachment, optic nerve compressive lesion | Urgent |
| Chronic bilateral | Refractive error, bilateral cataracts, POAG, AMD, diabetic retinopathy, toxic/nutritional optic neuropathy | Routine |
Investigations
GP Access
Visual acuity (Snellen)
Bedside; MBS item 10610 (optometric), but GP assessment is free of MBS constraint
GP Access
Intraocular pressure (IOP) — non-contact or Goldmann tonometry
Available in many GP practices; referral for formal measurement if not available
GP Access
Fundoscopy — direct ophthalmoscopy or fundus camera
Dilated exam with tropicamide 1%; diabetic retinal photography MBS item 12325
Referral
Optical coherence tomography (OCT)
Gold standard for macular and optic nerve head assessment; available in ophthalmology and optometry practices
Referral
Automated perimetry (Humphrey visual fields)
Essential for glaucoma staging and neurological field defects
Referral
Slit-lamp examination
Anterior segment assessment, gonioscopy for angle evaluation
Referral
Fluorescein angiography (FFA)
Retinal vascular assessment; diabetic retinopathy, retinal vein occlusion, wet AMD
Specialist
MRI brain and orbits (with gadolinium)
Suspected optic neuritis, intracranial mass, demyelination; bulk-billed under Medicare
Specialist
Erythrocyte sedimentation rate (ESR) & CRP
Suspected GCA — ESR >50 mm/hr highly suggestive; urgent if >50 years with visual loss
Specialist
Temporal artery biopsy
Gold standard for GCA diagnosis; should be performed within 2 weeks of commencing corticosteroids
Refractive Errors & Cataracts
Refractive Errors
Refractive errors are the most common cause of visual impairment globally and are responsible for the majority of presentations of blurred vision in primary care. They occur when the optical system of the eye fails to focus light precisely on the retina.
| Type | Mechanism | Presentation | Correction |
|---|---|---|---|
| Myopia (short-sightedness) | Image focused in front of retina — elongated globe or steep cornea | Blurred distance vision, clear near vision; squinting | Concave (minus) lenses — spectacles or contact lenses |
| Hyperopia (long-sightedness) | Image focused behind retina — short globe or flat cornea | Blurred near ± distance; eye strain, headache in younger patients (compensated by accommodation) | Convex (plus) lenses |
| Astigmatism | Unequal curvature of cornea/lens causing two focal points | Blurred/distorted vision at all distances; headache | Cylindrical (toric) lenses |
| Presbyopia | Age-related loss of lens accommodation (onset ~45 years) | Difficulty with near work — reading, phone use; holds objects at arm's length | Reading glasses, bifocals, or progressive lenses |
Refractive error assessment is primarily performed by optometrists (MBS item 10610 for comprehensive eye examination) or ophthalmologists. In Australia, Medicare covers one comprehensive eye examination per 12 months by a registered optometrist without requiring a GP referral. Contact lens fitting is also available under MBS optometric items.
Progressive myopia in children: The prevalence of myopia is increasing in Australian children, particularly in East Asian background populations. Evidence-based myopia control strategies include low-dose atropine (0.01–0.05%) eye drops, orthokeratology, and specialised peripheral defocus contact lenses. Referral to a paediatric optometrist or ophthalmologist is recommended if myopia is progressing >0.50 D/year.
Cataracts
A cataract is any opacification of the crystalline lens. Age-related cataract is by far the most common type and is a universal consequence of ageing, though the rate of progression varies. In Australia, cataract surgery is the most frequently performed surgical procedure, with over 250,000 operations per year.
Classification of Cataracts
| Type | Risk Factors / Causes | Features |
|---|---|---|
| Nuclear sclerotic | Ageing, UV exposure, smoking | Hardening/yellowing of lens nucleus; initial myopic shift ("second sight"); gradual bilateral blurring |
| Cortical | Diabetes, UV exposure | Spoke-like opacities from periphery; glare, especially driving at night |
| Posterior subcapsular (PSC) | Corticosteroids, diabetes, radiation, uveitis | Most visually significant; affects near vision early; severe glare; rapid progression |
| Congenital | Intrauterine infection (rubella, CMV), genetic syndromes (Down, Turner, Marfan), metabolic (galactosaemia) | Leukocoria; requires urgent referral — amblyopia risk |
| Traumatic | Blunt or penetrating ocular trauma | Rosette-shaped opacity; may present years after injury |
Indications for Cataract Surgery
Cataract surgery is indicated when visual impairment from cataract interferes with the patient's quality of life, daily activities (driving, reading, work), or when the cataract impedes management of other eye conditions (e.g., fundal view for diabetic retinopathy). There is no fixed acuity threshold; the decision is based on functional impact shared between patient and ophthalmologist.
Cataract surgery in Australia: Phacoemulsification with intraocular lens (IOL) implantation is performed as a same-day procedure under topical or local anaesthesia. Medicare covers the procedure (MBS item 42724). Public hospital wait times average 3–12 months depending on state; private surgery can be arranged within weeks. Toric and multifocal IOLs are available at additional out-of-pocket cost.
Pre-operative Assessment
- Biometry — axial length and keratometry for IOL power calculation (IOLMaster or A-scan ultrasound)
- Assessment of co-existing ocular pathology — macular degeneration, glaucoma, diabetic retinopathy
- Endothelial cell count if corneal guttae or prior corneal disease suspected
- Consent discussion — risks include posterior capsule rupture (~1–2%), endophthalmitis (~0.04%), cystoid macular oedema, retinal detachment (especially in high myopia), dropped nucleus
- Pre-operative drops: topical NSAID (nepafenac or ketorolac) to reduce cystoid macular oedema risk; povidone-iodine 5% for antisepsis
Post-operative Management
Standard post-operative regimen (typically prescribed by the ophthalmologist):
Prednisolone acetate 1% eye drops
Prednefrin Forte® · Corticosteroid
Dose
1 drop QID for 2 weeks, then taper over 4–6 weeks
Notes
Tapering schedule varies by surgeon; monitor IOP during steroid use
PBS status
✔ PBS General Benefit
Moxifloxacin 0.5% eye drops
Vigamox® · Fluoroquinolone antibiotic
Dose
1 drop QID for 1–2 weeks post-operatively
Notes
Some surgeons use combined antibiotic-steroid drops (e.g., Tobradex®)
PBS status
✔ PBS General Benefit
Post-cataract emergency — Endophthalmitis: Any eye pain, redness, or worsening vision in the first 6 weeks after cataract surgery should be treated as endophthalmitis until proven otherwise. Refer immediately to an ophthalmologist for vitreous tap and intravitreal antibiotic injection (vancomycin 1 mg/0.1 mL + ceftazidime 2.25 mg/0.1 mL). Incidence: ~1 in 1,000 surgeries.
Chronic Glaucoma & Macular Degeneration
Chronic Glaucoma
Glaucoma is a progressive optic neuropathy characterised by loss of retinal ganglion cells and corresponding visual field defects, usually associated with raised intraocular pressure (IOP). It is the second most common cause of irreversible blindness worldwide. In Australia, approximately 300,000 people have glaucoma, with half remaining undiagnosed.
Types of Glaucoma
| Type | Mechanism | Demographics | Clinical Features |
|---|---|---|---|
| Primary open-angle glaucoma (POAG) | Chronic trabecular meshwork dysfunction → gradual IOP rise → optic nerve damage | Most common type; prevalence increases with age; family history; African descent higher risk | Insidious; peripheral visual field loss first; central vision affected late; painless |
| Normal-tension glaucoma | Optic nerve damage despite IOP in "normal" range (≤21 mmHg); vascular/ischaemic factors | More common in Japanese and Korean populations; association with migraines, Raynaud's | Similar field loss to POAG; disc haemorrhages common |
| Acute angle-closure glaucoma | Sudden blockage of trabecular meshwork by peripheral iris → rapid IOP rise | Hypermetropic (long-sighted) eyes; older females; dilated pupil risk; Southeast Asian heritage | Emergency: painful red eye, mid-dilated fixed pupil, hazy cornea, nausea/vomiting, IOP often >40 mmHg |
| Secondary glaucoma | Steroid-induced, pseudoexfoliation, pigment dispersion, neovascular (diabetes/CRVO), uveitic | Variable; steroid-induced can occur at any age | Find underlying cause; may present as acute or chronic |
| Childhood glaucoma | Primary congenital (trabeculodysgenesis); developmental anomalies | 1 in 10,000 births; bilateral in 70% | Buphthalmos, photophobia, tearing, corneal clouding, Haab's striae |
Acute angle-closure glaucoma is an ophthalmological emergency. If suspected, immediately commence topical timolol 0.5%, pilocarpine 2%, and oral acetazolamide 500 mg (if no sulphonamide allergy). Arrange emergency ophthalmology review within hours — laser peripheral iridotomy is definitive treatment. Delay risks permanent vision loss within hours to days.
Diagnosis of POAG
- IOP: Normal range 10–21 mmHg (mean 15.5 mmHg). Diagnosis does NOT require IOP >21 — normal-tension glaucoma accounts for ~30% of cases.
- Optic disc assessment: Cup-to-disc ratio >0.6, cup-to-disc ratio asymmetry >0.2 between eyes, disc haemorrhage, neuroretinal rim thinning (ISNT rule).
- Gonioscopy: Essential to distinguish open-angle from angle-closure. Performed by ophthalmologist using a goniolens.
- Visual field testing: Humphrey automated perimetry (24-2 or 30-2); arcuate (Bjerrum) scotoma and nasal step are characteristic.
- OCT: Retinal nerve fibre layer (RNFL) and ganglion cell analysis — detects structural loss before field defects manifest.
- Central corneal thickness (CCT): Thin corneas (<555 μm) underestimate IOP and are an independent risk factor for POAG progression.
Pharmacological Treatment of Glaucoma
The goal of treatment is to lower IOP to a target level (typically 25–30% reduction from baseline) to slow or halt optic nerve damage. Treatment is lifelong. Medications are applied topically as eye drops.
Latanoprost 0.005%
Xalatan® · Prostaglandin analogue (PGA)
Dose
1 drop in affected eye(s) once daily at night
Mechanism
Increases uveoscleral outflow; IOP reduction 25–35%
Counsel
Iris colour change (blue → brown), periorbital fat atrophy, eyelash growth; remove contact lenses before instillation
PBS status
🔒 PBS Authority Required — Streamlined authority code 8621
Timolol 0.5%
Timoptol® · Beta-blocker (non-selective β1/β2)
Dose
1 drop BD (morning and evening)
Mechanism
Decreases aqueous humour production; IOP reduction 20–25%
Counsel
Avoid in asthma/COPD, heart failure, heart block; nasolacrimal occlusion to reduce systemic absorption; may mask hypoglycaemia in diabetics
PBS status
✔ PBS General Benefit
Brimonidine 0.2%
Alphagan® · Alpha-2 agonist
Dose
1 drop TDS (or BD with Purite® preservative-free formulation)
Mechanism
Decreases aqueous production, increases uveoscleral outflow; IOP reduction 18–25%
Counsel
Avoid in children <2 years (CNS depression); caution with MAOIs; may cause allergic conjunctivitis in up to 12% after prolonged use
PBS status
🔒 PBS Authority Required
Dorzolamide 2%
Trusopt® · Carbonic anhydrase inhibitor (CAI)
Dose
1 drop TDS (or BD in combination with timolol as Cosopt®)
Mechanism
Decreases aqueous humour production; IOP reduction 15–20%
Counsel
Sulphonamide derivative — avoid in sulphonamide allergy; bitter taste; stinging on instillation
PBS status
🔒 PBS Authority Required
Acetazolamide
Diamox® · Systemic carbonic anhydrase inhibitor
Acute dose
500 mg PO or IV stat, then 250 mg QID
Chronic dose
125–250 mg PO BD (sustained-release formulation)
Mechanism
Inhibits carbonic anhydrase in ciliary body; reduces aqueous production
Counsel
Avoid in sulphonamide allergy, severe renal/hepatic failure; monitor potassium; paraesthesia, fatigue, metabolic acidosis common; renal calculi risk with prolonged use
PBS status
✔ PBS General Benefit
Surgical and Laser Options for Glaucoma
- Laser peripheral iridotomy (LPI): First-line treatment for angle-closure; creates a small hole in peripheral iris to equalise pressure. Bilateral (prophylactic on fellow eye).
- Selective laser trabeculoplasty (SLT): First-line option for POAG (LiGHT trial evidence); equivalent to eye drops in newly diagnosed POAG; repeatable; reduces medication burden.
- Trabeculectomy: Gold-standard filtration surgery for medically uncontrolled glaucoma. Anti-metabolites (mitomycin C, 5-fluorouracil) used to improve success rates.
- Glaucoma drainage devices (tube shunts): For refractory glaucoma, neovascular glaucoma, or failed trabeculectomy.
- Minimally invasive glaucoma surgery (MIGS): iStent, Hydrus, XEN gel stent — often combined with cataract surgery; lower efficacy but safer profile than trabeculectomy.
Age-Related Macular Degeneration (AMD)
AMD is a progressive, degenerative disease of the macula and is the leading cause of legal blindness in Australians over 50. An estimated 1.7 million Australians have some evidence of AMD, with prevalence doubling every decade after age 50 (Macular Disease Foundation Australia, 2023).
Classification and Features
Early AMD
Early / Intermediate AMD
Medium-sized drusen (63–124 μm), pigmentary changes. Usually asymptomatic. Amsler grid normal. Annual monitoring recommended.
Setting: Optometrist/GP annual review
Late Dry (GA)
Geographic Atrophy (Dry AMD)
Progressive atrophy of RPE and photoreceptors; large confluent drusen. Gradual central vision loss; difficulty reading, recognising faces. No approved treatment in Australia until recently — pegcetacoplan (Syfovre®) approved by TGA 2024 for GA.
Setting: Ophthalmologist monitoring every 3–6 months
Late Wet (nAMD)
Neovascular (Wet) AMD
Choroidal neovascularisation → fluid, haemorrhage, and fibrosis under retina. Rapid central vision loss, metamorphopsia, central scotoma. Requires urgent intravitreal anti-VEGF therapy.
Setting: Ophthalmologist — intravitreal injection clinic (monthly loading phase)
Amsler grid self-monitoring: All patients with intermediate AMD (or the fellow eye of patients with late AMD) should be provided with an Amsler grid for home monitoring. New distortion or missing areas should prompt urgent ophthalmology review within 1–2 weeks, as conversion to wet AMD may benefit from immediate anti-VEGF treatment.
Intravitreal Anti-VEGF Therapy for Wet AMD
Ranibizumab 0.5 mg
Lucentis® · Anti-VEGF-A antibody fragment
Dose
0.5 mg (0.05 mL) intravitreal injection monthly × 3 months loading, then PRN or treat-and-extend
Administration
Intravitreal injection in sterile procedure room; topical anaesthesia; povidone-iodine antisepsis
Counsel
Risks: endophthalmitis (~1/2,000), retinal detachment, vitreous haemorrhage, transient IOP rise
PBS status
🔒 PBS Authority Required (Specialist)
Aflibercept 2 mg
Eylea® · VEGF Trap (fusion protein)
Dose
2 mg (0.05 mL) intravitreal injection monthly × 3 months, then every 2 months (or treat-and-extend)
Advantage
Potentially fewer injections than ranibizumab with comparable visual outcomes (VIEW trials)
PBS status
🔒 PBS Authority Required (Specialist)
Aflibercept 8 mg (high-dose)
Eylea HD® · High-dose VEGF Trap
Dose
8 mg intravitreal injection — loading q4 weeks × 3, then q8–16 weeks (PULSAR trial data)
Advantage
Extended dosing intervals (up to 16 weeks); may improve adherence
PBS status
🔒 PBS Authority Required (Specialist) — TGA approved 2024
Modifiable Risk Factors for AMD Progression
Lifestyle Modifications
- Smoking cessation — most important modifiable risk factor (3–4× risk increase)
- UV protection (sunglasses, hat) — recommended but evidence is observational
- Regular exercise — associated with reduced AMD progression
- Weight management and cardiovascular risk reduction
Nutritional Supplementation (AREDS2 Formula)
- For intermediate AMD (bilateral large drusen) or advanced AMD in one eye:
- Lutein 10 mg + Zeaxanthin 2 mg
- Vitamin C 500 mg + Vitamin E 400 IU
- Zinc 80 mg + Copper 2 mg
- No benefit for early AMD or for smokers (beta-carotene excluded in AREDS2 due to lung cancer risk)
- Available OTC; not PBS-listed
Optic Neuropathies & Visual Failure in Children and the Elderly
Optic Neuropathies
Optic neuropathies are a heterogeneous group of disorders affecting the optic nerve, presenting with visual loss, colour vision impairment (particularly red desaturation), a relative afferent pupillary defect (RAPD), and characteristic visual field defects. The differential diagnosis requires careful history, examination, and often neuroimaging.
| Type | Demographics | Presentation | Investigation / Treatment |
|---|---|---|---|
| Optic neuritis (demyelinating) | Young adults (20–40 years), F > M; associated with MS | Subacute painful vision loss (hours–days), pain on eye movement, central scotoma, dyschromatopsia. Vision typically improves over weeks. | MRI brain and orbits (look for demyelinating lesions); IV methylprednisolone 1 g daily for 3 days, then oral prednisolone taper (hastens recovery, does not change final outcome). See ONTT trial. |
| Non-arteritic anterior ischaemic optic neuropathy (NAION) | Age >50; "disc at risk" (small crowded disc, C/D <0.1); vascular risk factors (diabetes, hypertension, obstructive sleep apnoea) | Sudden painless unilateral vision loss (often noticed on waking); altitudinal field defect; disc swelling (usually segmental/pallid); usually no treatment available — prevent fellow eye: manage vascular risk factors, screen for OSA | No proven treatment; avoid PDE-5 inhibitors (sildenafil, tadalafil); screen for obstructive sleep apnoea |
| Arteritic anterior ischaemic optic neuropathy (A-AION) — Giant cell arteritis | Age >50; peaks 70–80 years; F > M | Ophthalmological emergency: Sudden severe painless vision loss; may have preceding transient visual obscurations (amaurosis fugax); jaw claudication, scalp tenderness, headache, polymyalgia rheumatica, weight loss, fever | Immediate high-dose steroids — do NOT wait for biopsy: IV methylprednisolone 500 mg–1 g/day for 3 days, then oral prednisolone 1 mg/kg/day. ESR, CRP, FBC (normochromic normocytic anaemia, thrombocytosis). Temporal artery biopsy within 2 weeks. |
| Compressive optic neuropathy | Any age; pituitary tumour, meningioma, craniopharyngioma, thyroid eye disease | Gradual progressive vision loss; may have bitemporal hemianopia (chiasmal); proptosis if orbital | MRI brain and orbits with contrast; neurosurgical/ENT referral |
| Toxic/nutritional optic neuropathy | Ethambutol, methanol, tobacco-alcohol, vitamin B12/folate deficiency | Bilateral symmetric gradual vision loss; cecocentral scotoma; reduced colour vision | Discontinue offending agent; B12/folate levels; B12 replacement if deficient; monitor vision recovery |
| Leber hereditary optic neuropathy (LHON) | Young males (15–35 years); mitochondrial DNA mutations (m.11778G>A most common) | Sequential bilateral subacute painless vision loss (second eye typically affected within weeks–months); pseudo-oedema of disc; telangiectatic peripapillary vessels | Genetic testing (mtDNA); idecene (Raxone® — not yet PBS-listed in Australia); avoid alcohol and smoking |
Giant cell arteritis — sight-saving urgency: Any patient >50 years presenting with new visual loss (even transient), jaw claudication, or new-onset headache must have ESR and CRP checked immediately. If clinical suspicion is high, commence IV methylprednisolone 500 mg–1 g before results return. The fellow eye is at imminent risk (up to 25% within days). Do NOT wait for a temporal artery biopsy result to initiate treatment.
Visual Failure in Children
Visual failure in children requires prompt assessment because the developing visual system is vulnerable to irreversible damage (amblyopia) during the critical period (birth to 7–8 years).
Key Paediatric Causes of Visual Failure
| Condition | Age at Presentation | Key Features | Management |
|---|---|---|---|
| Amblyopia | Detectable from 6 months; critical period <7 years | Reduced vision in one eye not correctable by refractive means; most common cause of unilateral visual impairment in children. Causes: strabismus (35%), anisometropia (35%), deprivation (cataract, ptosis) | Correct refractive error first (spectacles); then occlusion therapy — patching the better eye 2–6 hours/day (dose depends on severity); atropine penalisation as alternative; monitor for reverse amblyopia |
| Congenital cataract | Newborn (red reflex screening at birth) | Absent or abnormal red reflex; leukocoria; may be unilateral or bilateral. Bilateral cases: consider metabolic, genetic, intrauterine infection (TORCH) | Urgent ophthalmology referral; surgical extraction within first 6 weeks of life (bilateral) or urgently (unilateral to prevent amblyopia); post-operative aphakic correction (contact lens or IOL); intensive amblyopia treatment |
| Retinoblastoma | Median 18 months; 95% diagnosed before age 5 | Leukocoria (white pupillary reflex) — most common presenting sign (~60%); strabismus (~20%); may present with glaucoma, hyphaema, or proptosis in advanced disease | Urgent referral to ocular oncology centre (RVEEH Melbourne, Sydney Children's Hospital); globe-salvaging therapy: intra-arterial chemotherapy, intravitreal melphalan, laser, cryotherapy; enucleation if advanced; genetic testing (RB1 gene) essential |
| Retinopathy of prematurity (ROP) | Premature infants <32 weeks or <1,500 g birth weight | Neovascularisation at the vascular–avascular retina junction; screening mandated for at-risk neonates in Australian NICUs | Screening from 31–33 weeks corrected gestational age (ANZNN guidelines); laser photocoagulation or intravitreal anti-VEGF for treatment-requiring ROP (Type 1); retinal detachment requires vitreoretinal surgery |
| Infantile nystagmus | Onset usually by 3 months | Rhythmic oscillation of eyes; may indicate underlying visual pathway pathology (albinism, Leber congenital amaurosis, achromatopsia, foveal hypoplasia, cataract) | Full ophthalmic and neurological assessment; MRI brain if structural cause suspected; prism correction; gabapentin or memantine (off-label) for acquired nystagmus in selected cases |
| Childhood glaucoma | Usually by age 3 (primary congenital) | Buphthalmos (enlarged globe), photophobia, tearing, cloudy cornea, Haab's striae, high IOP | Surgery is first-line — goniotomy or trabeculotomy; topical IOP-lowering drops as adjunct; lifelong follow-up |
Leukocoria (white pupil) in a child is retinoblastoma until proven otherwise. Urgent referral to a specialist ophthalmologist is required — do not delay for routine optometry referral. Other causes include Coats' disease, persistent fetal vasculature, toxocariasis, and retinopathy of prematurity. Delayed diagnosis of retinoblastoma significantly worsens prognosis and increases the likelihood of enucleation or metastatic disease.
Visual Failure in the Elderly
Visual impairment in older adults is common and significantly under-recognised. It is associated with increased falls, depression, social isolation, cognitive decline, and loss of driving independence. The Royal Australian and New Zealand College of Ophthalmologists (RANZCO) recommends annual eye examinations for all adults over 65.
Unique Considerations in the Elderly
1
Multi-morbidity
Elderly patients frequently have multiple concurrent causes of visual loss (e.g., cataract + glaucoma + AMD + diabetic retinopathy). Treating one condition may unmask another. Comprehensive assessment is essential.
2
Falls and Fractures
Visual impairment doubles the risk of falls. Cataract surgery has been shown to reduce fall rates by 34% in randomised controlled trials. Assess for home hazards and refer to falls prevention programmes.
3
Medication Burden
Eye drops may be difficult to self-administer (arthritis, cognitive impairment). Consider preservative-free formulations, sustained-release options, or carer-assisted instillation. Avoid topical beta-blockers in severe asthma or bradycardia.
4
Driving Safety
Legal visual acuity requirement for driving in Australia is 6/12 (both eyes together, with correction if needed). GPs have a legal and ethical obligation to advise patients who no longer meet this standard and to notify the relevant state licensing authority if the patient does not self-report.
5
Low-Vision Rehabilitation
For irreversible visual impairment, refer to Vision Australia (1300 84 74 66) or equivalent state service. Interventions include magnification devices, electronic reading aids, home modifications, orientation and mobility training, and assistive technology. GP Management Plans (GPMP, MBS item 721) can support allied health referrals.
Monitoring & Follow-up
Monitoring frequency depends on the underlying condition, risk of progression, and whether the patient is on active treatment. The following provides a general guide aligned with RANZCO and ophthalmological best practice:
Every 1–2 years
Low-risk adults (no known eye disease): Comprehensive eye examination from age 40 (RANZCO recommendation); annually from age 65. Includes visual acuity, IOP measurement, and optic disc assessment.
Every 12 months
Diabetic patients: Dilated fundoscopy or retinal photography (MBS item 12325) from diagnosis of type 2 diabetes (or 5 years after diagnosis of type 1). More frequently if established retinopathy.
Every 6–12 months
Glaucoma suspects and treated glaucoma: IOP, visual fields (Humphrey perimetry), OCT of RNFL and optic nerve head. More frequent (3–6 months) if newly diagnosed, post-laser, or with progressive field loss.
Every 3–6 months
Wet AMD on anti-VEGF: Visual acuity, OCT, and clinical assessment at each injection visit. Treat-and-extend protocols adjust intervals based on disease activity (fluid on OCT).
Every 6–12 months
Intermediate AMD (no treatment): Amsler grid self-monitoring at home; regular review with optometrist or ophthalmologist; immediate review if new metamorphopsia or scotoma.
4–6 weeks post-operatively
Post-cataract surgery: First review by the operating ophthalmologist; refraction at 4–6 weeks for final spectacle prescription. Resume optometrist/GP care thereafter.
Lifelong (3-monthly initially)
Paediatric amblyopia treatment: Frequent reviews during occlusion therapy (every 6–8 weeks initially). Confirm compliance and monitor for reverse amblyopia. Continue until stable visual acuity achieved or age ~8–10 years.
GP role in monitoring: GPs play a critical role in coordinating care, reinforcing medication adherence (eye drops in glaucoma), managing systemic risk factors (blood pressure, HbA1c, lipids), screening for driving fitness, and facilitating referrals. The GP Management Plan (MBS item 721) and Team Care Arrangement (MBS item 723) allow structured follow-up with optometrists and allied health professionals.
Aboriginal and Torres Strait Islander Health
Aboriginal and Torres Strait Islander Australians experience significantly higher rates of visual impairment and blindness compared with non-Indigenous Australians. According to the 2022 National Eye Health Survey and AIHW reporting, Indigenous Australians are:
- Three times more likely to be blind than non-Indigenous Australians
- Have higher rates of uncorrected refractive error — particularly in remote communities with limited access to optometry services
- Experience disproportionately high rates of diabetic retinopathy due to the significantly higher prevalence of type 2 diabetes (3–4 times that of non-Indigenous Australians)
- Are the only population group in high-income countries where trachoma (Chlamydia trachomatis) remains endemic — prevalence exceeds 5% in some remote communities in the Northern Territory, Western Australia, and South Australia
- Have lower rates of cataract surgery and longer wait times compared with non-Indigenous Australians, despite higher cataract prevalence
Action for GPs: When reviewing Aboriginal and Torres Strait Islander patients, specifically ask about vision ("Can you see clearly for reading? For distance?"). Check for spectacle use and red reflex. Ensure diabetic patients are up to date with retinal screening. Document findings and arrange appropriate referrals. Use the Indigenous Health Check (MBS item 715) as a prompt for a structured eye health assessment.
📚 References
- 1. Australian Institute of Health and Welfare (AIHW). Eye health indicators for Aboriginal and Torres Strait Islander people 2022. Canberra: AIHW; 2023. Available from: https://www.aihw.gov.au
- 2. Macular Disease Foundation Australia. Macular disease in Australia 2023 — prevalence and impact. Sydney: MDFA; 2023.
- 3. Royal Australian and New Zealand College of Ophthalmologists (RANZCO). Position statement: Eye health and vision care. Sydney: RANZCO; 2022.
- 4. Heijl A, Leske MC, Bengtsson B, et al. Reduction of intraocular pressure and glaucoma progression: results from the Early Manifest Glaucoma Trial. Arch Ophthalmol. 2002;120(10):1268–1279.
- 5. Gazzard G, Konstantakopoulou E, Garway-Heath D, et al. Selective laser trabeculoplasty versus eye drops for first-line treatment of ocular hypertension and glaucoma (LiGHT): a multicentre randomised controlled trial. Lancet. 2019;393(10180):1505–1516.
- 6. Age-Related Eye Disease Study 2 Research Group. Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration: the Age-Related Eye Disease Study 2 (AREDS2) randomized clinical trial. JAMA. 2013;309(19):2005–2015.
- 7. Schmidt-Erfurth U, Kaiser PK, Korobelnik JF, et al. Intravitreal aflibercept injection for neovascular age-related macular degeneration: ninety-six-week results of the VIEW studies. Ophthalmology. 2014;121(1):193–201.
- 8. Optic Neuritis Study Group (ONTT). The 5-year risk of multiple sclerosis after optic neuritis: experience of the Optic Neuritis Treatment Trial. Neurology. 1997;49(5):1404–1413.
- 9. Hellmich B, Agueda A, Monti S, et al. 2018 Update of the EULAR recommendations for the management of large vessel vasculitis. Ann Rheum Dis. 2020;79(1):19–30.
- 10. Prevent Blindness Australia and Vision 2020 Australia. National Eye Health Survey 2016 — final report. Melbourne: Centre for Eye Research Australia; 2016.
- 11. Taylor HR, Xie J, Fox S, et al. The prevalence and causes of vision loss in Indigenous Australians: the National Indigenous Eye Health Survey. Med J Aust. 2010;192(6):312–318.
- 12. Hoy SM. Pegcetacoplan: first approval. Drugs. 2023;83(14):1303–1310. [Geographic atrophy treatment — TGA approval Australia 2024]
- 13. The Royal Australian and New Zealand College of Ophthalmologists (RANZCO). Clinical guideline: Cataract surgery in Australia. 2021.
- 14. Dirani M, Tong L, Gazzard G, et al. Outdoor activity and myopia in Singapore teenage children. Br J Ophthalmol. 2009;93(8):997–1000.
- 15. World Health Organization. Ending the neglect to attain the Sustainable Development Goals: a road map for neglected tropical diseases 2021–2030 — trachoma. Geneva: WHO; 2020.