MODULE 1 · GDFM PROGRAMME

Acute Eye Conditions in Primary Care

📅 🏛 College of Family Physicians Singapore
GDFM Programme · College of Family Physicians Singapore CFPS

Learning Objectives

  • 💎 Perform a structured ocular history and physical examination
  • 💎 Differentiate the key causes of the acute red eye
  • 💎 Identify ocular red flags requiring immediate referral
  • 💎 Describe initial management of Acute Angle-Closure Glaucoma
  • 💎 Recognise sudden visual disturbances — retinal detachment, optic neuritis, temporal arteritis
  • 💎 Understand when NOT to start treatment before specialist review (e.g., microbial keratitis)
GDFM Programme · College of Family Physicians Singapore CFPS

Ocular Assessment: History Red Flags

  • 🚨 Pain, photophobia, acute blurring of vision — always serious
  • 🚨 Flashes and/or multiple new floaters → rule out retinal detachment
  • 🚨 Haloes around lights → suggests raised IOP (angle-closure glaucoma)
  • 🚨 Recent contact lens use or high-velocity trauma
  • 💎 Ask about DM, HTN, autoimmune disease, drug history (anticholinergics, chloroquine)
  • 💎 Occupation matters — grinding/hammering raises suspicion for penetrating injury
GDFM Programme · College of Family Physicians Singapore CFPS

Ocular Examination: Key Steps

  • 💎 Visual acuity (Snellen) with and without pinhole — always first
  • 💎 Pupillary reactions: direct, consensual, swinging flashlight test for RAPD
  • 💎 Penlight: corneal clarity, ciliary flush, hypopyon, anterior chamber depth
  • 💎 Fluorescein staining with cobalt blue light to detect corneal defects
  • 💎 Evert upper eyelid to exclude subtarsal foreign body
  • 💎 Fundoscopy: optic disc, macula, vessels; check red reflex
GDFM Programme · College of Family Physicians Singapore CFPS

Fundoscopic Findings

  • 💎 Diabetic maculopathy: hard exudates, microaneurysms, haemorrhages
  • 💎 Glaucoma: increased cup-to-disc ratio (>0.6 suspicious, >0.7 significant)
  • 💎 Dry AMD: drusen deposits (yellow-white spots) at the macula
  • 🚨 CRAO: pale retina + cherry-red spot + attenuated vessels — ocular emergency
  • 💎 Optic atrophy: pale disc — late sequela of optic neuritis or raised ICP
  • 💎 Post-PRP scars in treated proliferative diabetic retinopathy
GDFM Programme · College of Family Physicians Singapore CFPS

Red Eye: Differential at a Glance

  • 💎 Conjunctivitis: diffuse redness, discharge, normal vision, normal pupil
  • 💎 Anterior Uveitis: ciliary flush, photophobia, small/irregular pupil
  • 🚨 Acute Angle-Closure Glaucoma: mid-dilated fixed oval pupil, hazy cornea, rock-hard globe
  • 🚨 Microbial Keratitis: corneal infiltrate/ulcer, contact lens history — do not start ABx
  • 💎 Scleritis: deep violaceous colour, boring pain, systemic disease association
  • 💎 Episcleritis: sectoral pink redness, self-limiting, sclera remains white
GDFM Programme · College of Family Physicians Singapore CFPS

Conjunctivitis: Viral vs Bacterial vs Allergic

  • 💎 Viral (adenovirus): watery discharge, preauricular node, recent URTI — supportive Rx only
  • 💎 Bacterial: purulent sticky discharge, lids stuck in AM — topical chloramphenicol
  • 💎 Allergic: bilateral, intense itch, atopy history — antihistamine/mast cell stabiliser
  • 🚨 Neonatal purulent discharge: always suspect gonococcal/chlamydial — refer immediately
  • 💎 Quinolones reserved for severe bacterial cases or corneal involvement
  • 💎 Hygiene counselling essential for viral conjunctivitis (highly contagious)
GDFM Programme · College of Family Physicians Singapore CFPS

Serious Red Eye: Uveitis & Pterygium

  • 🚨 Anterior Uveitis: perilimbal injection, dull aching pain, photophobia — urgent referral
  • 💎 Causes: idiopathic, ankylosing spondylitis, sarcoidosis, IBD, syphilis, TB, herpes
  • 💎 Tx: topical steroids + cycloplegics — not to be started in primary care without ophthalmologist
  • 💎 Pterygium: nasal fibrovascular growth onto cornea; lubricants for symptoms
  • 💎 Refer pterygium if encroaching on visual axis or growing rapidly
  • 💎 Scleritis: associated with RA, SLE, vasculitis — urgent referral + oral NSAIDs
GDFM Programme · College of Family Physicians Singapore CFPS

Acute Angle-Closure Glaucoma: Initial Management

🚨 Emergency — Act Now
🚨
  • 🚨 Emergency: sudden severe eye pain, N&V, halos, mid-dilated fixed pupil, hazy cornea
  • 💎 Definitive Tx = Laser Peripheral Iridotomy (LPI) — arrange emergency transfer
  • 💎 While awaiting: Pilocarpine 2–4% drops (×2, q15 min) + Brimonidine 0.15% (×2, q15 min)
  • 💎 Systemic IOP reduction: Acetazolamide 500 mg PO (IV if nauseated)
  • 💎 Refractory IOP: IV Mannitol 25–50 g (20% solution)
  • 🚨 Treat fellow eye prophylactically with pilocarpine
GDFM Programme · College of Family Physicians Singapore CFPS

Sudden Visual Disturbances

  • 🚨 New floaters + flashes + visual field curtain = retinal detachment until proven otherwise
  • 🚨 CRAO: pale retina + cherry-red spot — refer urgently (4–6 hour window)
  • 🚨 Temporal arteritis: >50 yrs, jaw claudication, headache — immediate high-dose steroids
  • 💎 PVD: benign age-related floaters; urgent dilated fundoscopy to exclude RD
  • 💎 Vitreous haemorrhage: sudden floaters/blobs — refer to exclude RD
  • 💎 Metamorphopsia (wavy vision): macular pathology — wet AMD or central serous retinopathy
GDFM Programme · College of Family Physicians Singapore CFPS

Optic Neuritis & Anisocoria

  • 💎 Optic Neuritis triad: subacute unilateral visual loss + pain on eye movement + dyschromatopsia
  • 💎 Key sign: RAPD (Marcus Gunn pupil) — swinging flashlight test
  • 🚨 IV corticosteroids hasten recovery; oral prednisolone alone is CONTRAINDICATED
  • 🚨 Anisocoria in light (larger pupil abnormal): CN III palsy — rule out posterior communicating aneurysm
  • 🚨 Anisocoria in dark (smaller pupil abnormal) + neck pain: Horner's + carotid dissection — emergency
  • 💎 Optic atrophy (pale disc) is a late sign — develops weeks after acute optic neuritis
GDFM Programme · College of Family Physicians Singapore CFPS

Key Summary

Key Point
🚨 Red Flags: severe pain, vision loss, photophobia, fixed mid-dilated pupil, hazy cornea, penetrating trauma, sudden floaters/flashes
Key Point
🚨 Do Not Miss: AACG, Microbial Keratitis, Retinal Detachment, Orbital Cellulitis, Temporal Arteritis
Key Point
💎 Exam Essentials: Visual acuity FIRST, pupillary reactions, fluorescein staining, lid eversion
Key Point
💎 Never start antibiotics before referral for microbial keratitis (scraping needed)
Key Point
💎 Never prescribe topical anaesthetics for home use
Key Point
💎 Safety net ALL patients: return immediately if pain worsens or vision deteriorates
GDFM Programme · College of Family Physicians Singapore CFPS

References

  • Azari AA, Barney NP. Conjunctivitis. JAMA. 2013;310(16):1721-9.
  • Shah SM, Khanna CL. Ophthalmic Emergencies. Mayo Clin Proc. 2020;95(5):1050-1058.
  • Nguyen V, Lee GA. Microbial keratitis in general practice. Aust J Gen Pract. 2019;48(8):516-9.
  • Heath Jeffery RC et al. Unequal pupils. Aust J Gen Pract. 2019;48(1-2):39-42.
  • Gariano RF, Kim CH. Suspected retinal detachment. Am Fam Physician. 2004;69(7):1691-8.
  • UpToDate. Optic neuritis: Prognosis and treatment. Accessed July 2024.
  • Glaucoma Today. Management of AACG in an Emergent Setting. 2025 May-Jun.
GDFM Programme · College of Family Physicians Singapore CFPS