Cases/Ophthalmology

Rapid Vision Loss — Free SCA Practice Case

Elderly man with rapid vision loss

Station Timer

12:00

Golden Minute

Initial Introduction

•Introduce yourself

•Ask an open question — "How can I help you today?"

•Listen — don't interrupt

•Catch early cues

Data Gathering

History, ICE & Diagnosis

Clinical Management

Diagnosis, Plan & Decisions

Safety Net

Follow-up & Close

12:00

Golden Minute

Materials for Candidate

Please review before starting the consultation

Patient Profile

Full Name

Arthur Pennyworth

Age

78 years

Consultation Type

Video

Age

78 (DOB: 12/03/1947)

Situation

Video Consultation.

Reason for Encounter

"My eyesight has gone downhill rapidly in the last few weeks. I need new glasses."

Medical Records

●
PMH:
- ●Dry Age-Related Macular Degeneration (diagnosed 3 years ago by Optometrist).
- ●Hypertension.
●Medications: Ramipril 5mg OD. MacuShield (Vitamin supplement).
●Allergies: NKDA.

Recent Notes

●1 Year Ago: Routine Optician review. "Dry AMD stable. Drusen present. Visual Acuity 6/9 bilateral."

Patient Script

For the friend playing the patient role

Character Overview: You are Arthur. You are an independent, sharp-minded retired engineer. You rely heavily on your sight for your hobbies (crosswords, model trains). You are frustrated because you bought new reading glasses at the chemist last week and they "didn't work." You assume you just need a stronger prescription, but you are secretly terrified of going blind.

Opening Sentence: "Good morning, Doctor. I need a referral for an eye test or something. Over the last month, my right eye has just given up. I can't read the newspaper anymore, even with my glasses. It's all just a smudge in the middle."

History if Asked (Data Gathering Phase)

●
The Vision Loss:
- ●Speed: "It was fine at Christmas (1 month ago). Now, when I look at the crossword, the black squares are grey."
- ●Distortion (Metamorphopsia): "The strangest thing is the bathroom tiles. I know they are straight, but when I look with my right eye, the lines look wavy and bent. Like a funhouse mirror."
- ●Central vs Peripheral: "I can see the clock on the wall, but I can't see the hands. It's right in the middle that's the problem."
●
Red Flag Screening (GCA/Detachment/Glaucoma):
- ●Pain: "No pain at all. No redness."
- ●Flashes/Floaters: "No flashing lights."
- ●Headache: "No headaches. My scalp is fine when I comb my hair." (Rules out Giant Cell Arteritis).
●
Examination Expectation:
- ●"Can't you look in my eye with that light? I've got a torch here if it helps?" (You don't understand that a GP video consult can't see the retina).

ICE — Ideas, Concerns, Expectations

●Ideas: "I thought I just needed stronger glasses — maybe the prescription has changed. But the chemist ones didn't help and now I'm starting to wonder if it's that macular thing the optician told me about a few years back. She said it was the 'dry' kind and it would stay slow, so I don't understand why this has happened so fast."
●Concerns: "I'm terrified I'm going to go blind, Doctor. I live on my own. If I can't read, can't do my models, can't drive to the shops — what am I going to do? I've always been independent and the thought of needing someone to look after me is worse than any of it."
●Expectations: "I just want someone to look at my eye properly and tell me what's going on. And if there's something that can be done, I want it done quickly — before it gets any worse. I can't sit on a three-week waiting list while my sight disappears."

If Asked — Medical History and Medications

●Dry AMD diagnosis: "The optician picked it up about three years ago. She said I had some spots at the back of my eye — drusen, I think she called them. She said it was the dry type and that it usually progresses slowly. I've been going back every year and it's been stable until now."
●MacuShield: "I take those eye vitamins — MacuShield. The optician suggested them when I was first diagnosed. I take one a day, been doing it for about three years. I don't know if they actually do anything but I thought it couldn't hurt."
●Hypertension: "I've had high blood pressure for years. It's been well controlled as far as I know — the nurse checks it every six months or so."
●Ramipril: "I take a tablet every morning for the blood pressure — Ramipril, 5mg. Been on the same dose for a good while now. No problems with it."
●Allergies: "No, no allergies to anything that I know of."

Social History and Lifestyle Impact

●Occupation / daily life context: Arthur is a retired mechanical engineer, widowed, living alone in a semi-detached house. He is fiercely independent — does his own shopping, cooking, and drives himself to the supermarket and the model railway club twice a week.
●Lifestyle impact of the condition: "I can't do my crossword anymore — that used to be my morning routine with a cup of tea and now I just sit there staring at a blur. My model trains are even worse — I've been building a new signal box and I can't see the small parts to glue them. I had to put it all away. And I nearly knocked a cyclist off last week because I didn't see him until the last moment — scared me half to death. Honestly, Doctor, without my sight I don't know what I'd do with myself. It's everything."

If Asked — Associated Symptoms

●If asked about the left eye: "The left eye seems alright — not perfect, mind you, but I can still read with it if I close the right one. It's the right that's the problem."
●If asked about double vision: "No, nothing like that. It's not doubled — it's just blurred and smudgy in the middle."
●If asked about eye discharge or watering: "No discharge or anything like that. My eyes aren't sticky or weepy."
●If asked about colour vision changes: "Now you mention it, colours do look a bit duller in that right eye — not as vivid as they used to be. But it's the blurriness that bothers me most."
●If asked about night vision: "It's worse in dim light, definitely. I've stopped reading in the evening because I can't see the page even with the lamp on."
●If asked about any injury or trauma to the eye: "No, nothing like that. I haven't bumped it or got anything in it."
●If asked about a curtain or shadow coming across the vision: "No, it's not like a curtain. It's more like someone has smeared Vaseline right in the centre."
●If asked about jaw pain or pain when chewing: "No, nothing like that at all."
●If asked about shoulder or hip stiffness: "No, I'm a bit creaky in the mornings but nothing unusual for my age."
●If asked about recent weight loss or fatigue: "No, I'm eating fine and I've got plenty of energy. It's just the eye."

Responses to Management (The Negotiation Phase)

●
If the Doctor suggests 'Dry AMD progression':
- ●Reaction: "But the optician said the dry type takes years! This happened in three weeks. Surely that's not right?"
●
If the Doctor mentions 'Injections in the eye':
- ●Reaction: Horrified. "A needle? In my eyeball? Is that the only way? Will it save my sight?"
●
If the Doctor discusses Driving:
- ●Reaction: Defensive. "I only drive to the shops. I can see the road fine, it's just reading that's hard. You aren't going to take my license, are you?"
●
If the Doctor refers to an Optician:
- ●Reaction: "I tried to book, but they said there's a 3-week wait. I can't wait that long, Doctor. I'm losing my independence."

Mark Scheme

Domain 1: Data Gathering and Diagnosis

0 / 16 indicators checked+0−0

Positive (0/8)

Negative (0/8)

Domain 2: Clinical Management and Medical Complexity

0 / 22 indicators checked+0−0

Positive (0/11)

Negative (0/11)

Domain 3: Relating to Others

0 / 16 indicators checked+0−0

Positive (0/8)

Negative (0/8)

Clinical Learning Points

Distinguishing Dry from Wet (Neovascular) AMD

●Dry AMD is characterised by slow, progressive atrophy of the retinal pigment epithelium over years, with drusen (yellow subretinal deposits) visible on fundoscopy. There is no licensed treatment; management is with AREDS2-formula supplements and lifestyle modification.
●Wet (neovascular) AMD occurs when pathological choroidal new vessels (CNV) grow beneath the macula and leak fluid or blood, causing rapid and severe central vision loss — typically over weeks, not years.
●The cardinal symptom of wet AMD is metamorphopsia — distortion of straight lines (e.g. door frames, bathroom tiles appear wavy or bowed). This directly reflects subretinal fluid distorting the overlying photoreceptors.
●A central scotoma (blurred or missing central vision with preserved peripheral vision) is the other defining feature — patients can see the clock face but not the hands.
●Dry-to-wet conversion is the critical transition: up to 15% of patients with dry AMD develop neovascular conversion. This can occur in one eye while the other remains stable. Rapid unilateral deterioration on a background of known dry AMD should be treated as wet AMD until proven otherwise.
●The Amsler grid is the standard home-monitoring tool: a grid of straight lines with a central dot. Patients with dry AMD should be instructed to test each eye separately weekly and attend urgently if lines appear distorted or a blank area develops.

Red Flag Differentials in Acute Visual Loss

●In any patient over 50 presenting with acute monocular visual loss, Giant Cell Arteritis (GCA) must be excluded as a first priority — this is an ophthalmic and rheumatological emergency. Screen for: temporal or frontal headache, scalp tenderness (pain on combing hair), jaw claudication, and systemic features (fatigue, weight loss, proximal girdle aching). A raised ESR and CRP supports the diagnosis; urgent high-dose prednisolone and same-day secondary care referral are required if suspected.
●Retinal detachment presents with sudden visual field loss (often described as a 'curtain' or 'shadow' across vision), preceded by new-onset photopsia (flashing lights) and floaters. It requires same-day emergency ophthalmology review.
●Acute angle-closure glaucoma presents with severe unilateral eye pain, redness, halos around lights, headache, nausea, and visual blurring. It is an ocular emergency requiring same-day review.
●In this case, the absence of pain, redness, flashes/floaters, headache, scalp tenderness, or jaw claudication, combined with the clinical pattern of metamorphopsia and central scotoma on a background of dry AMD, points clearly to wet AMD conversion rather than these emergencies — but all three must be actively screened for and excluded.

Investigations

●This is primarily a clinical diagnosis made on history; in a video consultation, formal visual acuity testing and fundoscopy are not possible.
●A useful remote functional assessment is to ask the patient to cover each eye separately and look at a straight-edged surface (door frame, window frame, or a sheet of lined paper) to confirm or elicit distortion — this approximates an informal Amsler grid test.
●Definitive diagnosis is made in secondary care via optical coherence tomography (OCT), which confirms the presence of subretinal fluid and CNV, and guides anti-VEGF treatment decisions. Fluorescein angiography may also be used.
●Do not delay referral to arrange investigations in primary care — the speed of the referral pathway is the priority.

Urgent Referral and the Rapid-Access Macular Clinic

●Suspected wet AMD requires urgent referral to the hospital eye service / rapid-access macular clinic, with a target of assessment within 1–2 weeks of referral. Many areas have dedicated macular pathways.
●Do not refer to a standard high-street optician for wet AMD — routine optician appointments carry waiting times that are clinically unacceptable for a time-sensitive condition. Refer directly to the macular clinic or, where available, via the community optometry urgent referral scheme with a confirmed rapid-access contract.
●The urgency of referral must be communicated clearly to the patient: treatment is most effective when started promptly, and delay risks irreversible photoreceptor damage and permanent central vision loss.
●If the referral is rejected or delayed beyond the expected timeframe, escalate via the practice or chase directly — do not leave the patient without follow-up.

Treatment — Anti-VEGF Intravitreal Injections

●The standard treatment for wet AMD is intravitreal anti-VEGF therapy — injections of a vascular endothelial growth factor inhibitor directly into the vitreous cavity of the eye, given by an ophthalmologist.
●Licensed agents used in NHS practice include ranibizumab (Lucentis), aflibercept (Eylea), and bevacizumab (Avastin), with faricimab (Vabysmo) increasingly used. The choice is made by the specialist; candidates do not need to know dose or interval details.
●The mechanism is inhibition of VEGF-driven pathological angiogenesis, reducing vascular leak, resolving subretinal fluid, and stabilising the macula.
●Prognosis: Anti-VEGF therapy stabilises vision in approximately 90% of patients and improves vision in around 30%. It is a maintenance treatment, not a cure — most patients require ongoing injections (initially monthly, then as-needed or treat-and-extend regimens).
●Patients should understand that treatment cannot restore vision that has already been permanently lost, but that starting promptly gives the best chance of preserving remaining vision.
●The eye is fully anaesthetised with topical drops before the procedure; the injection itself takes seconds. Acknowledging the patient's anxiety about needles and explaining the anaesthesia and brevity of the procedure is important for informed consent and concordance.

MacuShield and AREDS2 Supplements

●MacuShield (lutein, zeaxanthin, meso-zeaxanthin) is an AREDS2-formula antioxidant supplement widely used for dry AMD. Evidence (AREDS2 trial) supports a modest reduction in the risk of progression to advanced AMD in patients with intermediate or advanced dry AMD in one eye.
●Supplements do not treat or prevent wet AMD — once neovascular conversion has occurred, anti-VEGF therapy is required. Patients should not be led to believe that taking supplements will reverse or halt wet AMD.
●There is no indication to stop MacuShield: it may still have a role for the dry AMD component and there is no harm in continuing. Advise the patient to continue as before.

Driving and the DVLA

●The legal visual standard for driving a car in the UK (Group 1 licence) requires: visual acuity of at least 6/12 on the Snellen scale using both eyes together (or one eye if the other is absent or blind), and a visual field meeting the binocular Esterman standard (no significant defects in the central or lower visual fields).
●A patient with significant central vision loss in one eye should stop driving and seek ophthalmological assessment before returning to the wheel — the ability to meet the legal standard must be confirmed, not assumed.
●DVLA notification is required if the condition affects both eyes, affects the only functioning eye, causes a visual field defect, or reduces acuity below the legal standard. If a patient with wet AMD in one eye retains adequate acuity and field in the other eye and meets the standard overall, they may be permitted to drive — but this determination must be made by the specialist, not assumed in primary care.
●Candidates must raise driving proactively when the history reveals a functional impact on driving safety (e.g. near-miss with a cyclist). Failure to address this is a patient safety failure.
●Frame the discussion sensitively: driving restriction is described as temporary pending specialist assessment, practical alternatives are explored (delivery services, community transport, family support), and the clinical and legal rationale is explained clearly without being punitive.

Safety Netting — Monitoring the Fellow Eye

●Patients with unilateral wet AMD have a significantly elevated risk of developing neovascular conversion in the fellow eye — approximately 10–15% per year in some estimates.
●All patients should be instructed to self-monitor the fellow eye regularly using the Amsler grid or by checking straight-edged objects at home. Each eye should be tested separately.
●Any new distortion, central blurring, or scotoma in the fellow eye should prompt immediate contact with the macular clinic (not the GP surgery) — this is a clinical emergency with the same urgency as the index presentation.
●Ensure the patient leaves the consultation with a clear plan: what to watch for, in which eye, and who to contact and how quickly.

Holistic and Psychosocial Considerations

●Sudden central vision loss in an elderly patient living alone has consequences far beyond the clinical — it threatens functional independence (driving, reading, hobbies, self-care), social connection, and psychological wellbeing.
●The risk of depression and social isolation is significant in patients with new visual impairment. This should be acknowledged in the consultation and followed up after the specialist assessment.
●Signpost to relevant support services: RNIB (Royal National Institute of Blind People) provides practical support, talking books, and peer support. Local authority social services can arrange a needs assessment. Low vision clinics offer practical aids.
●If the specialist confirms significant permanent visual impairment, the patient may be eligible for registration as sight impaired or severely sight impaired (previously 'partially sighted' and 'blind'), which unlocks a range of statutory benefits and support services — this can be discussed at follow-up once the clinical picture is clearer.

Common Candidate Mistakes

●Accepting the presenting complaint at face value: Wet AMD does not present as 'needing stronger glasses.' Candidates who take the patient's self-diagnosis at face value and arrange an optician referral will fail to identify the time-critical diagnosis. The clinical pattern — rapid unilateral onset, metamorphopsia, central scotoma, background of dry AMD — must be recognised and acted on.
●Diagnosing 'worsening dry AMD': Dry AMD progresses over years. A three-week deterioration is not dry AMD progression — it is wet AMD until proven otherwise. Failing to recognise this distinction is the most common diagnostic error in this case.
●Routine optician referral instead of urgent macular clinic referral: A three-week optician wait for suspected wet AMD risks irreversible macular scarring. Candidates must know the urgent referral pathway.
●Omitting GCA screening: Any patient over 50 with acute visual loss requires active GCA exclusion. Failing to ask about scalp tenderness and jaw claudication is a patient safety error.
●Avoiding the driving discussion: Arthur describes a near-miss with a cyclist. Candidates who do not raise driving proactively are failing on both clinical management and patient safety grounds.
●Giving false reassurance about prognosis: Telling a patient that treatment will restore their vision is incorrect and constitutes a consent failure. The honest message — treatment can preserve the vision that remains but may not recover what is already lost — must be communicated clearly and compassionately.

Free MRCGP SCA practice case for GP registrars covering Rapid Vision Loss — Ophthalmology. Includes candidate brief, patient script, marking scheme mapped to the RCGP SCA marking domains, and learning points. Built directly from the RCGP curriculum topic stations listed under "How this might be tested in the MRCGP SCA," part of a free library of 79 SCA practice cases for simulated consultation assessment preparation.

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