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Ophthalmology Postings: History Taking & Examination Guide
Source: Kanski's Clinical Ophthalmology: A Systematic Approach, 10th edition
PART 1 - HISTORY TAKING
The Ophthalmic History Framework
A basic ophthalmic history has the following components:
1. Main Complaint
For every symptom, ask:
- Rapidity of onset - sudden vs. gradual? Sudden painless loss of vision suggests vascular causes (CRAO, CRVO, vitreous hemorrhage); gradual suggests refractive error, cataract, glaucoma.
- Circumstances of onset - after trauma, on waking, after reading?
- Severity - how much vision is affected? Can they count fingers, read, drive?
- Duration - hours, days, weeks, months?
- Frequency - constant, intermittent, episodic (e.g., amaurosis fugax)?
Common presenting symptoms to probe:
| Symptom | Key questions |
|---|
| Blurred vision | Near or distance? One eye or both? Transient or persistent? |
| Pain | Aching (raised IOP), sharp/gritty (corneal/conjunctival), deep boring (uveitis, scleritis) |
| Redness | Unilateral/bilateral? Discharge? Painful or painless? |
| Diplopia | Monocular (corneal/lens) vs. binocular (muscle/nerve)? Horizontal/vertical? |
| Flashes (photopsia) | Duration, frequency - suggests retinal traction or migraine |
| Floaters | New or longstanding? Sudden shower of floaters = vitreous hemorrhage/retinal tear |
| Haloes around lights | Corneal oedema (acute glaucoma) vs. lens changes |
| Distortion (metamorphopsia) | Central - suggests macular pathology (AMD, CSCR) |
| Field loss | Which part of vision - central, peripheral, one side? |
| Photophobia | Uveitis, corneal abrasion, keratitis, meningitis |
| Discharge | Mucopurulent (bacterial), watery (viral), stringy/ropy (allergic) |
| Watering (epiphora) | Excessive tear production vs. impaired drainage? |
2. Past Ocular History
- Previous eye surgery (cataract, vitrectomy, strabismus, laser)
- Previous ocular inflammation (uveitis, scleritis)
- Previous trauma
- Glasses/contact lens use - which type, how long?
- Previous laser or intravitreal injections
- Amblyopia or squint in childhood
3. Past Medical History
Important systemic associations:
- Diabetes - diabetic retinopathy, cataract, cranial nerve palsies
- Hypertension - hypertensive retinopathy, BRAO, BRVO
- Thyroid disease - thyroid eye disease (proptosis, lid lag, diplopia)
- Rheumatoid arthritis / SLE - dry eye, scleritis, uveitis
- HIV/immunosuppression - CMV retinitis, toxoplasmosis
- Sarcoidosis - uveitis, retinal vasculitis
- Multiple sclerosis - optic neuritis
4. Systemic Medications
- Corticosteroids (topical or systemic) - posterior subcapsular cataract, raised IOP
- Tamsulosin / alpha blockers - intraoperative floppy iris syndrome (IFIS) - critical to know before cataract surgery
- Hydroxychloroquine - bull's eye maculopathy
- Amiodarone - corneal verticillata, optic neuropathy
- Ethambutol - toxic optic neuropathy
- Vigabatrin - visual field defects
- Topiramate - acute angle closure
5. Allergies
- Antibiotic drops (neomycin, chloramphenicol)
- Topical glaucoma medications
- Contact lens solution preservatives
6. Family History
- Glaucoma - most important; first-degree relatives have 4-9x risk
- Macular degeneration (AMD)
- Inherited retinal dystrophies (retinitis pigmentosa, Stargardt disease)
- Squint or amblyopia
- Refractive error (high myopia)
7. Social History
- Occupation (VDU use, outdoor work, occupational hazards)
- Driving (legal requirement to mention if affected)
- Smoking (major risk factor for AMD and diabetic retinopathy progression)
- Alcohol
PART 2 - OPHTHALMIC EXAMINATION
The examination is systematic and follows the path of light from the outside in: lids → conjunctiva → cornea → anterior chamber → iris/pupil → lens → vitreous → fundus.
Step 1: Visual Acuity (VA) - The Single Most Important Test
Distance VA:
- Use a Snellen chart at 6 metres (or LogMAR/ETDRS chart which is preferred in trials for accuracy)
- Test each eye separately - cover the other eye
- Always test with best correction (glasses/contact lenses)
- If the patient cannot see the top letter at 6m, move them closer and record (e.g., 3/60)
- If still no letters: Count Fingers (CF), Hand Motion (HM), Perception of Light (PL), or No Perception of Light (NPL)
- Use a pinhole if VA is reduced - improvement with pinhole suggests a refractive cause rather than organic pathology
Near VA:
- Use a near vision chart (e.g., Jaeger test types) held at a comfortable distance (~33cm)
- Sensitive for early macular disease
- Note if patient uses reading glasses
Step 2: Colour Vision
- Use Ishihara plates (test for red-green deficiency - screens for optic nerve disease)
- Useful in optic neuritis (red desaturation is an early sign)
- A light brightness comparison test can be done informally: hold a pen torch alternately in front of each eye and ask the patient to compare brightness - a dim perception in one eye suggests relative afferent pupillary defect (RAPD) or optic neuropathy
Step 3: Visual Fields
- Confrontation testing (bedside): Sit opposite the patient at arm's length. Cover one eye each. Bring a finger in from the periphery in each quadrant. Compare with your own field as reference.
- For subtle defects use a red hatpin - colour desaturation in a scotoma is detected before white-target loss
- Formal fields: Humphrey automated perimetry (standard in glaucoma monitoring), Goldmann kinetic perimetry
- Amsler grid - for central/macular distortion; the patient fixates on the central dot and reports if any lines appear wavy or missing (metamorphopsia in AMD, CSCR)
Step 4: Pupil Examination
Always examine pupils before dilating the eye.
- Size and symmetry at rest (anisocoria?)
- Direct light reflex - shine a light in one eye, the same pupil constricts
- Consensual reflex - the opposite pupil also constricts
- Swinging flashlight test for RAPD (Relative Afferent Pupillary Defect): Swing a torch from eye to eye every 2-3 seconds. If the pupil dilates when the light is swung to it (paradoxical dilation), there is an RAPD in that eye - indicating optic nerve disease or severe retinal disease on that side.
- Accommodation reflex - ask patient to look at a distant object then at your finger close up; pupil should constrict and eyes converge
Step 5: Ocular Motility & Cover Test
Ocular movements:
- Ask patient to follow your finger through the 9 positions of gaze (H-pattern)
- Note any limitation, pain, or diplopia in any position
- Look for nystagmus
Cover test (for squint/strabismus):
- Cover-uncover test: Cover one eye; watch the uncovered eye for movement (movement = manifest deviation/tropia)
- Alternating cover test: Rapidly alternate cover from eye to eye; detects latent deviation (phoria)
Step 6: External Examination
Systematic inspection from outside in:
- Periorbital: Swelling, bruising, skin lesions, ptosis
- Lids:
- Ptosis (measure levator function: MRD1 = margin-to-reflex distance)
- Entropion, ectropion, trichiasis
- Lid margin - styes, chalazion, blepharitis (look for meibomian gland dysfunction, lid margin telangiectasia, crusting)
- Eversion of upper lid to look for foreign bodies (papillae, follicles)
- Conjunctiva:
- Injection pattern: conjunctival (peripheral/fornices, mobile with conjunctiva), ciliary/circumcorneal (limbal, fixed - suggests corneal/anterior segment disease)
- Discharge: purulent, mucopurulent, serous
- Follicles (viral, chlamydial) vs. papillae (allergic, bacterial)
- Subconjunctival hemorrhage, chemosis, pterygium, pinguecula
- Cornea:
- Clarity - opacities, scars, infiltrates, ulcers
- Size - microcornea, megalocornea, buphthalmos
- Fluorescein staining under cobalt blue light - reveals epithelial defects (abrasion, ulcer, exposure, HSV dendrite)
- Anterior chamber:
- Depth (shallow = angle closure risk)
- Hyphema (blood), hypopyon (pus - white/yellow level)
- Look obliquely across with a slit lamp for flare and cells (uveitis)
- Iris:
- Colour, posterior synechiae (adhesions to lens from uveitis), rubeosis (new vessels - suggests ischaemia)
- Iridodonesis (trembling = aphakia or lens subluxation)
- Lens:
- Clarity - nuclear sclerosis (yellow/brown), posterior subcapsular (PSC), anterior/posterior cortical cataracts
- Position - subluxation in Marfan syndrome, homocystinuria
Step 7: Slit Lamp Biomicroscopy (Anterior Segment)
This is the core examination tool in ophthalmology. It provides a binocular, magnified, illuminated view of the anterior segment.
Slit lamp techniques:
- Diffuse broad beam - general survey, gross abnormalities
- Direct focal illumination (narrow slit beam) - assess depth and layering of corneal lesions, lens opacities
- Scleral scatter - decenter the beam to the limbus; detects subtle corneal stromal haze/infiltrates
- Retroillumination - reflects light from iris or fundus to illuminate cornea from behind; shows epithelial cysts, keratic precipitates (KPs), corneal blood vessels
- Specular reflection - assess corneal endothelium; shows guttata, reduced cell density
Key things to document at slit lamp:
- Keratic precipitates (KPs): small/stellate (non-granulomatous uveitis) vs. large mutton-fat (granulomatous uveitis e.g. sarcoid, TB)
- Anterior chamber cells (grade 0-4+) and flare
- Corneal staining with fluorescein
Step 8: Intraocular Pressure (IOP)
- Normal range: 10-21 mmHg
- Goldmann applanation tonometry - the gold standard; done at slit lamp after instilling topical anaesthetic and fluorescein
- Non-contact tonometry (air puff) - screening only, less accurate
- Icare rebound tonometer - no anaesthetic needed, useful for children and bedside
- Perkins tonometer - portable, for supine/examination under anaesthesia
Step 9: Gonioscopy (Angle Examination)
- Special contact lens placed on the anaesthetised eye to examine the iridocorneal angle
- Essential for classifying glaucoma (open angle vs. closed angle) and looking for neovascularization of the angle (rubeosis iridis)
- Shaffer grading of angle width (Grade 0 = closed to Grade 4 = wide open)
Step 10: Fundus Examination (Posterior Segment)
Always dilate the pupil first (tropicamide 1% ± phenylephrine 2.5%) unless contraindicated (shallow anterior chamber, need to monitor pupil neurology).
a) Direct Ophthalmoscopy:
- Handheld, provides 15x magnification
- Upright, monocular image - no stereopsis, small field of view
- Useful at bedside
- Technique: examiner on same side as eye being examined, use same eye as patient's eye
- Start with red reflex check from ~25cm (lens/vitreous opacities block the reflex)
- Then approach to ~3cm, find the optic disc by directing the beam slightly nasally
b) Indirect Ophthalmoscopy (Head-Mounted BIO):
- Wide field of view, stereoscopic, inverted & laterally reversed image
- Penetrates media opacities better than slit lamp
- Essential for peripheral retina (retinal detachment, peripheral tears)
- Use with scleral indentation for far periphery
c) Slit Lamp with Non-Contact Lens (+78D or +90D):
- Best for detailed posterior pole examination (macula, disc)
- Inverted, virtual image
- Most common method in clinic
What to examine systematically in the fundus:
| Structure | What to look for |
|---|
| Optic disc | Cup:disc ratio (normal <0.5), disc margin clarity, pallor, swelling (papilloedema), haemorrhages, notching |
| Macula | Foveal reflex, drusen, haemorrhage, exudates, pigmentary changes, membranes, holes |
| Vessels | AV ratio (normal 2:3), arteriovenous nipping, silver/copper wiring, haemorrhages (flame = superficial, dot/blot = deep), exudates (hard = lipid, soft = cotton wool spots = NFL infarcts), neovascularization |
| Peripheral retina | Lattice degeneration, holes, tears, detachment |
| Vitreous | Haemorrhage, cells (asteroid hyalosis, inflammation), posterior vitreous detachment |
Quick Reference: The Ophthalmology Examination Order
- VA (with correction + pinhole)
- Colour vision (Ishihara)
- Visual fields (confrontation, Amsler grid)
- Pupils (direct, consensual, swinging torch for RAPD)
- Ocular motility + cover test
- External examination (lids, adnexa)
- Slit lamp (anterior segment: conjunctiva, cornea, AC, iris, lens)
- IOP (Goldmann applanation)
- Gonioscopy (if glaucoma suspected)
- Dilated fundus exam (disc, macula, vessels, periphery)
Practical tips for postings:
- Always examine both eyes and compare - most findings are more meaningful in context of the fellow eye.
- Document findings using standard abbreviations: RE/LE (right/left eye), BCVA, RAPD, KPs, AC cells/flare grade, C:D ratio.
- Learn to use the slit lamp early - it takes practice. Start with wide beam on low magnification, then narrow down.
- The Amsler grid and confrontation fields take 1-2 minutes but yield enormous diagnostic value - never skip them.
- When in doubt about IOP or disc changes, always refer to a senior or formal perimetry before dismissing the patient.
Source: Kanski's Clinical Ophthalmology: A Systematic Approach, 10th edition, Chapter 1