History Taking · Foundation · Ophthalmology

Visual Changes in the Central Field of Vision

Practise this PLAB 2 history taking station on Age-Related Macular Degeneration. 8-minute voice AI simulation with feedback on all 3 marking domains.

Clinical scenario

You are an FY2 doctor in a GP surgery. Mrs Jacqueline Knight, a 74-year-old woman, has come to see you because she has noticed that her central vision has become blurry and distorted over the past few weeks. She is finding it difficult to read and has some difficulty recognising faces. Please take a focused history and discuss initial management.

Background notes: PMH: Hypertension, Hypercholesterolaemia, Osteoarthritis (mild)

What this station tests

  • Metamorphopsia (wavy distortion of straight lines) as the hallmark of macular disease
  • Distinguishing wet AMD (rapid, treatable urgently with anti-VEGF) from dry AMD (slower, no acute treatment)
  • Urgent macular pathway referral: wet AMD requires assessment within 2 weeks for anti-VEGF to be effective
  • Reassuring about peripheral vision preservation: AMD does not cause total blindness
  • Amsler grid as a simple screening and home monitoring tool

How to use your 8 minutes

  • 0-1 min — Introduction: Introduce yourself, confirm identity, open question. 'What's brought you in today?'
  • 1-4 min — Systematic History: Presenting complaint detail (SOCRATES for pain, timeline, severity). Systems review. PMH, medications, allergies.
  • 4-6 min — Context and ICE: Social history (smoking, alcohol, occupation, living situation). Family history. Ideas, Concerns, Expectations.
  • 6-7 min — Summary and Plan: Summarise findings back to patient. Share differential/working diagnosis. Outline investigation and management plan.
  • 7-8 min — Closing: Safety netting with specific red flags. Arrange follow-up. Check for questions.

Consultation approach

The opening

Central visual distortion in an elderly patient is macular degeneration until proven otherwise. The urgency depends on the type: wet AMD is an emergency requiring urgent referral, dry AMD is slower. Mrs Knight is 74, presenting with 4 to 5 weeks of central vision blurring and distortion. Open with: 'Mrs Knight, changes to your central vision are something we take seriously. Tell me exactly what you are seeing.'

Core approach

Characterise the visual changes. Central vision blurry and distorted for 4 to 5 weeks. Straight lines appear wavy (metamorphopsia, the hallmark of macular disease). Difficulty reading (words distorted in the centre). Difficulty recognising faces. A dark or blank patch in the centre of vision. Peripheral vision preserved (she can see around the edges). This central loss with distortion is classic macular disease.

Determine dry versus wet AMD (critical for urgency). The 4 to 5 week progression with distortion raises concern for wet AMD (neovascular), which involves abnormal blood vessels leaking fluid under the macula. Wet AMD can cause rapid, permanent vision loss and requires urgent treatment (anti-VEGF injections). Dry AMD is slower and has no acute treatment. The distortion and relatively rapid progression favour wet.

Risk factors: age over 65, smoking history (ask), family history (her sister has AMD), hypertension, hypercholesterolaemia. Her sister's diagnosis is why she is connecting the dots.

Simple test: Amsler grid (if available) shows distortion of central lines, confirming macular pathology.

Closing and safety netting

Urgent referral. 'Mrs Knight, the distortion and blurring of your central vision needs urgent assessment by an eye specialist. There is a type of macular degeneration that can be treated if caught early, and I want to make sure you are seen quickly.' Refer to ophthalmology via the urgent macular pathway (most areas have a fast-track service for suspected wet AMD, target assessment within 2 weeks).

Provide realistic information: 'Macular degeneration affects the central part of your vision but it does not cause total blindness. Your peripheral vision is preserved, which means you will always be able to see around you.' If wet AMD is confirmed, anti-VEGF injections can stabilise and sometimes improve vision. Address driving: she may need a driving assessment depending on findings.

Safety net: 'If your vision suddenly gets worse before the appointment, go to A&E eye casualty.' Amsler grid for home monitoring if available.

How examiners mark this station

Examiners will focus on the thoroughness and structure of your history taking for age-related macular degeneration. Domain 1 (Data Gathering) carries the most weight: expect marks for systematic coverage of presenting complaint, red flags, PMH, medications, social and family history. Domain 2 (Clinical Management) requires a clear differential, appropriate investigations, and a safe management plan with safety netting. Domain 3 (Interpersonal Skills) is assessed throughout: genuine exploration of ICE, active listening, empathic responses, and clear communication without jargon.

Domain 1: Data Gathering, Technical and Assessment Skills (Primary focus)

Scores well: Central distortion characterised (metamorphopsia). Peripheral vision confirmed preserved. Wet vs dry risk assessed. Risk factors checked (smoking, family). Amsler grid used if available.

Costs marks: Not identifying central distortion pattern. Not considering wet vs dry. Not checking risk factors.

Domain 2: Clinical Management Skills (Primary focus)

Scores well: Urgent macular pathway referral. Anti-VEGF explained as potential treatment. Home monitoring with Amsler grid. Driving assessment mentioned. Safety netting for sudden deterioration.

Costs marks: Routine referral. Not knowing about anti-VEGF. No urgent pathway. No safety netting.

Domain 3: Interpersonal Skills (Throughout)

Scores well: Reassuring about peripheral vision preservation. Explaining urgency without causing panic. Addressing driving concern. Acknowledging sister's diagnosis as source of concern.

Costs marks: Not reassuring about blindness. Being either too casual or too alarming. Not addressing driving.

Common examiner feedback (and how to fix it)

Did not gather sufficient information to make an adequate assessment of the patient's condition

Fix: Use a consistent framework for every history. After covering the presenting complaint, systematically move through PMH, drug history, social history, family history, and ICE. Keep a mental checklist.

Did not identify the patient's problems and/or did not develop a management plan adequately

Fix: Reserve the final 2 minutes to summarise your findings, share your working diagnosis with the patient, and outline your investigation and management plan including safety netting.

Common mistakes in this station

  1. Not recognising the urgency of possible wet AMD. Central distortion progressing over weeks suggests wet AMD, which needs urgent treatment. Candidates who arrange routine ophthalmology referral risk permanent vision loss from treatment delay.
  2. Confusing AMD with cataracts. Cataracts cause generalised dimming and glare. AMD causes central distortion with preserved peripheral vision. The pattern is different and the management is completely different.
  3. Not reassuring about total blindness. Patients with macular degeneration fear going completely blind. AMD preserves peripheral vision. This reassurance is important and often omitted.

Resitting PLAB 2?

If you have previously struggled with history taking stations, focus on building a consistent systematic framework that you apply to every case. Practise structuring your history into clear phases (presenting complaint, systems review, PMH, social, ICE) so that even under pressure, you cover all domains. Many resitters lose marks not on knowledge but on organisation and time management.

Example opening

Good morning/afternoon, my name is Dr [Name], I'm one of the doctors here today. Could I confirm your name and date of birth please? Thank you. So, what's brought you in to see me today?

Frequently asked questions

How do I approach the consultation in this age-Related macular degeneration station?

Central visual distortion in an elderly patient is macular degeneration until proven otherwise. The urgency depends on the type: wet AMD is an emergency requiring urgent referral, dry AMD is slower. Mrs Knight is 74, presenting with 4 to 5 weeks of central vision blurring and distortion.

What does a strong performance look like to the examiner in this station?

Strong performances show: Central distortion characterised (metamorphopsia). Peripheral vision confirmed preserved. Wet vs dry risk assessed. Risk factors checked (smoking, family). Weak performances: Not identifying central distortion pattern. Not considering wet vs dry. Not checking risk factors.

What is the biggest pitfall in this age-Related macular degeneration station?

Not recognising the urgency of possible wet AMD. Central distortion progressing over weeks suggests wet AMD, which needs urgent treatment. Candidates who arrange routine ophthalmology referral risk permanent vision loss from treatment delay.

How should I prepare for age-Related macular degeneration if I have never seen it in practice?

Structure beats experience here. Focus on distinguishing wet AMD (rapid, treatable urgently with anti-VEGF) from dry AMD (slower, no acute treatment). The written guidance on this page covers the full approach, and practising the consultation aloud builds the fluency the examiner is listening for.

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