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OP9.1 | Ophthalmoscopy Technique and Normal Retina — SDL Guide (Part 3)
Practising and Perfecting: Applied Clinical Scenarios
Technique knowledge becomes clinical skill only through deliberate, supervised practice on real patients. These applied scenarios represent the contexts where your fundoscopy findings will directly change management — the highest-value moments for this skill in a general medical career.
Scenario 1 — Diabetic retinopathy screening. A 45-year-old woman with a 10-year history of type 2 diabetes attends a routine annual review. She has no visual complaints. You perform direct ophthalmoscopy through dilated pupils. You find bilateral microaneurysms and two dot haemorrhages in the right eye, and one hard exudate near the left macula. This is non-proliferative diabetic retinopathy (NPDR) — early stage. No NVD or NVE (no proliferative changes). Management: optimise glycaemic and BP control, refer to ophthalmologist within 3 months for formal grading and assessment for clinically significant macular oedema (CSME). Do NOT normalise this finding — CSME is the leading cause of blindness in diabetics and requires anti-VEGF or focal laser, which the ophthalmologist will assess.
Scenario 2 — Hypertensive emergency. A 62-year-old man presents with a severe headache and BP of 220/130 mmHg. On fundoscopy: bilateral flame haemorrhages, hard exudates in a macular star pattern, and swollen optic discs. This is hypertensive retinopathy grade IV (Keith-Wagener-Barker) with papilloedema — hypertensive emergency. Admit immediately for IV antihypertensive therapy under monitored conditions.
Scenario 3 — Suspected raised ICP. A 30-year-old woman with daily headaches, worse on lying down, and transient visual obscurations. Fundoscopy shows bilateral blurred superior and inferior disc margins with loss of venous pulsations — early papilloedema. This finding is a medical emergency: arrange urgent MRI brain/MRV to exclude venous sinus thrombosis or space-occupying lesion before LP.
Scenario 4 — Acute visual loss. A 70-year-old man with sudden painless total visual loss in one eye. On fundoscopy: pallid, milky-white retina with a cherry-red spot at the fovea. This is central retinal artery occlusion (CRAO) — a true ocular emergency. Management must begin within 90 minutes to have any chance of visual recovery: immediate referral to ophthalmology, ocular massage, and urgent work-up for carotid disease and cardiac embolic source.
Scenario 5 — Child with white pupil. A 2-year-old child brought in because the parents noticed a white glow in photographs. The red reflex is absent and replaced by a pale white reflex (leukocoria). This is retinoblastoma until proven otherwise — a life-threatening emergency requiring urgent ophthalmological referral. Do NOT reassure the parents.
SELF-CHECK
On fundoscopy of a diabetic patient, you see flame-shaped haemorrhages in all four quadrants, markedly dilated and tortuous veins, and disc swelling. What is the most likely diagnosis?
A. Proliferative diabetic retinopathy with neovascularisation on the disc
B. Central retinal vein occlusion (CRVO) — 'blood and thunder' fundus
C. Non-proliferative diabetic retinopathy with cotton-wool spots
D. Hypertensive retinopathy grade IV with papilloedema
Reveal Answer
Answer: B. Central retinal vein occlusion (CRVO) — 'blood and thunder' fundus
Flame haemorrhages in all four quadrants with severely dilated tortuous veins and disc swelling is the classic 'blood and thunder' fundus of CRVO (central retinal vein occlusion). PDR features neovascularisation (new vessel growth on the disc or retina) but not this pattern of all-quadrant flame haemorrhages with swollen disc. Hypertensive grade IV shows a different pattern: flame haemorrhages are present but accompanied by a macular star (hard exudates), and the veins are not as markedly dilated and tortuous as in CRVO.
Self-Assessment
Test your understanding of the ophthalmoscopy principles and normal fundus findings covered in this module. For each question, think through your reasoning before checking the answer.
Question 1. A colleague claims the image seen with a direct ophthalmoscope is 'real and inverted.' Is this correct? What is the correct description of the image?
Answer: Incorrect. The image with a direct ophthalmoscope is virtual and erect (upright). An erect, virtual, magnified image at approximately 15× is the characteristic of the direct instrument. The indirect ophthalmoscope produces a real and inverted image.
Question 2. You examine the optic discs of a 50-year-old and find a CDR of 0.6 in the right eye and 0.3 in the left eye. The IOP (measured separately) is 24 mmHg in the right and 16 mmHg in the left. What is the significance of the CDR asymmetry?
Answer: CDR asymmetry >0.2 between eyes is a red flag for glaucoma, especially when associated with elevated IOP. In this case, the right eye has both elevated IOP (>21 mmHg) and an enlarged CDR — this combination strongly suggests early glaucomatous damage to the right optic nerve. Refer for visual field testing and gonioscopy.
Question 3. On examining the macula, you notice the foveal reflex is absent and there is a subtle grey discolouration. What does this suggest, and what common clinical condition causes it?
Answer: Absence of the foveal reflex combined with macular grey discolouration suggests macular oedema — fluid accumulation within or beneath the central retina causing thickening that disrupts the foveal reflection. In the context of diabetics, this raises concern for clinically significant macular oedema (CSME), the leading cause of visual loss in diabetic retinopathy. Refer for optical coherence tomography (OCT) and consideration of anti-VEGF therapy.