Hypertensive retinopathy

Overview

•Chronic hypertensive retinopathy (BP >140/90 mmHg sustained) - usually asymptomatic, detected incidentally; bilateral and symmetric findings

•Accelerated (malignant) hypertension (BP >180/120 mmHg) - headache, decreased vision, disc swelling

•Fundoscopic signs (chronic, progressive): copper wiring → silver wiring → AV nipping → flame haemorrhages → hard exudates

•Fundoscopic signs (accelerated): cotton wool spots, flame haemorrhages, macular star, disc swelling (papilloedema)

🎯

Bilateral symmetric findings distinguish hypertensive retinopathy from retinal vein occlusion (unilateral). AV nipping and copper/silver wiring are the defining features of hypertensive retinopathy - absence should make you favour diabetic retinopathy. Neovascularisation rules IN proliferative diabetic retinopathy and rules OUT hypertensive retinopathy.

Investigations

🥇 First-line

•Fundoscopy - identifies and grades retinopathy; hallmark investigation

•Blood pressure measurement (clinic and ambulatory/home)

•Urine dipstick + protein:creatinine ratio - hypertensive nephropathy; ECG - left ventricular hypertrophy; bloods (U&Es, eGFR, HbA1c, fasting lipids) - target organ damage and cardiovascular risk

🏆 Gold standard

•Fluorescein angiography - detailed retinal vascular imaging in specialist settings

Differential diagnosis

⚠️

Hard exudates and haemorrhages alone are NOT enough to diagnose hypertensive retinopathy - they occur in diabetic retinopathy too. Look for AV nipping or copper/silver wiring to distinguish. In a patient with both hypertension and diabetes, absence of vascular changes (AV nipping, silver wiring) favours diabetic retinopathy.

Management

•Definitive treatment is control of underlying blood pressure - no direct ophthalmic intervention; retinal changes stabilise or partially regress with adequate BP control

🚨

Grade 4 hypertensive retinopathy (papilloedema + disc swelling) = accelerated (malignant) hypertension - hypertensive emergency requiring urgent admission and controlled BP reduction.

Complications

•Retinal vein occlusion (central or branch) - arteriosclerotic arteries compress retinal veins at AV crossings, predisposing to thrombosis; sudden painless unilateral vision loss with widespread haemorrhages

•Retinal artery occlusion - embolic/thrombotic; sudden painless unilateral vision loss; cherry-red spot on fundoscopy in central CRAO

•Permanent visual impairment - from macular ischaemia, macular oedema, or optic neuropathy in severe disease