Master Ophthalmology
for FMGE

What the FMGE Tests in Ophthalmology

The FMGE Ophthalmology section tests recognition and management of common ocular emergencies and chronic conditions. Candidates must differentiate red eye causes (conjunctivitis, keratitis, iritis, acute angle-closure glaucoma), apply Snellen visual acuity and intraocular pressure (IOP) cut-offs (normal IOP 10–21 mmHg), and know first-line treatments (e.g., topical antibiotics for bacterial conjunctivitis, timolol for glaucoma). Key decisions include when to refer urgently (e.g., corneal ulcer, retinal detachment, chemical burn). Knowledge of cataract surgery indications (visual acuity ≤6/12 or patient-reported disability), diabetic retinopathy staging (NPDR vs PDR), and amblyopia management (patching therapy before age 7) is essential. The exam also tests basic pharmacology (e.g., pilocarpine, atropine, acetazolamide) and trauma assessment (e.g., hyphema, ruptured globe).

High-Yield Concepts

• Red Eye Differential Diagnosis: Conjunctivitis: diffuse injection, watery/mucoid discharge, no photophobia, no corneal staining. Keratitis: circumcorneal injection, photophobia, fluorescein uptake (dendritic ulcer in HSV). Acute angle-closure glaucoma: severe pain, fixed mid-dilated pupil, IOP >40 mmHg, corneal edema; treat with pilocarpine 2%, acetazolamide 500 mg IV, then laser iridotomy. Iritis: ciliary flush, small irregular pupil, cells/flare in anterior chamber; treat with topical steroids and cycloplegics (e.g., atropine 1%).
• Glaucoma Management: Primary open-angle glaucoma (POAG): IOP >21 mmHg, optic disc cupping (cup-to-disc ratio >0.5), visual field defects. First-line: topical prostaglandin analogue (latanoprost 0.005% once daily). Acute angle-closure glaucoma: emergency—immediate acetazolamide 500 mg IV, topical timolol 0.5%, pilocarpine 2%, then laser iridotomy. Target IOP for POAG: 15–18 mmHg.
• Cataract Surgery Indications: Surgery indicated when visual acuity ≤6/12 (Snellen) or patient has significant functional impairment (e.g., glare, difficulty driving). Pre-op evaluation includes biometry (IOL power calculation), B-scan if dense cataract, and assessment of comorbidities (e.g., diabetic retinopathy). Most common procedure: phacoemulsification with posterior chamber IOL.
• Diabetic Retinopathy Staging and Treatment: Non-proliferative DR (NPDR): microaneurysms, dot-blot hemorrhages, hard exudates. Proliferative DR (PDR): neovascularization (disc or elsewhere), vitreous hemorrhage. Treatment: laser photocoagulation for high-risk PDR (e.g., neovascularization of disc >1/3 disc area) and for clinically significant macular edema (CSME: retinal thickening within 500 μm of fovea). Anti-VEGF (ranibizumab, aflibercept) first-line for DME.
• Amblyopia Management: Amblyopia (lazy eye) due to strabismus, anisometropia, or deprivation. Diagnosis: best-corrected visual acuity difference ≥2 lines between eyes. Treatment: refractive correction first, then patching the better eye (2–6 hours/day) or atropine 1% drops in the better eye. Critical period: age <7 years; earlier treatment yields better outcomes.
• Ocular Trauma: Chemical burn: immediate copious irrigation (normal saline or Ringer's lactate) for 30 minutes; check pH, then topical antibiotics (e.g., chloramphenicol) and cycloplegics. Hyphema (blood in anterior chamber): elevate head 30°, avoid aspirin, use topical steroids; measure IOP—if >30 mmHg, give acetazolamide. Ruptured globe: avoid pressure, shield eye, urgent surgical repair; no topical medications.
• Corneal Ulcer and Keratitis: Bacterial ulcer: corneal infiltrate, hypopyon, pain; corneal scrapings for Gram stain and culture; first-line topical fortified antibiotics (cefazolin 5% + gentamicin 1.4% or fluoroquinolone monotherapy). Fungal keratitis: risk factors (trauma with plant material, contact lens); slow onset, feathery margins; topical natamycin 5% or voriconazole 1%. HSV dendritic ulcer: topical acyclovir 3% ointment 5 times/day; avoid steroids.
• Retinal Detachment: Symptoms: sudden flashes (photopsia), floaters (often 'curtain' or 'shadow'), visual field loss. Signs: reduced visual acuity, relative afferent pupillary defect (RAPD), retinal tear on fundoscopy. Emergency: refer for scleral buckle or vitrectomy within 24–48 hours. Pre-op: head positioning to keep detachment away from macula. Risk factors: high myopia, aphakia, trauma.

Common Traps in Ophthalmology Questions

• Confusing acute angle-closure glaucoma with iritis: both cause red eye and photophobia, but glaucoma has fixed mid-dilated pupil and rock-hard eye, while iritis has small irregular pupil.
• Thinking that all red eye with discharge is infective conjunctivitis—consider allergic conjunctivitis (itching, cobblestone papillae) and keratitis (fluorescein staining, photophobia).
• Assuming normal IOP rules out glaucoma: normal-tension glaucoma (IOP <21 mmHg) exists and requires optic disc assessment and visual fields.
• Forgetting to shield the eye and avoid pressure in suspected ruptured globe—any manipulation can extrude intraocular contents.
• Using topical steroids in HSV keratitis without antiviral cover—this can worsen dendritic ulcers and cause corneal melting.
• Neglecting to check for RAPD (swinging flashlight test) in any patient with vision loss—this is a key sign of optic nerve or severe retinal disease.

How to Revise Ophthalmology for the FMGE

For FMGE Ophthalmology, prioritise red eye differentiation (especially acute angle-closure glaucoma vs iritis vs keratitis), glaucoma management (drug classes and IOP targets), and diabetic retinopathy treatment thresholds (CSME and PDR). Questions often present a clinical vignette with symptoms and signs, asking for the most likely diagnosis, next step (e.g., urgent referral, specific drop), or first-line drug. Practice interpreting Snellen acuity (e.g., 6/60 means sees at 6 m what normal sees at 60 m) and fundoscopy findings (e.g., disc cupping, neovascularization). Memorise key drug names: timolol, latanoprost, acetazolamide, pilocarpine, atropine, acyclovir, natamycin. Focus on emergency management (chemical burns, retinal detachment, acute glaucoma) as these are frequently tested. Use OSCE-style clinical reasoning: always check IOP, perform fluorescein staining, and assess pupillary reflexes.

Practise it: MedLumen has 50 Ophthalmology questions for the FMGE, each with a full explanation and references.