What’s going on?
The normal response to raised blood pressure is vasoconstriction of the retinal vasculature. This vasoconstriction tends to manifest fully only in younger patients, however, as their vessels still have some elasticity. Older patients by definition have pre-existing arteriolosclerosis, and therefore do not have this autoregulatory response. Sustained hypertension leads to rupture of blood vessels and breakdown of the blood-retinal barrier. Retinal haemorrhages, exudates and oedema occur, all of which results in blurred vision. In severe cases, the optic disc becomes swollen.
If I examine the patient, what will I find?
Marked thinning of the retinal arteries, ‘cotton wool’ spots, exudates and arteriovenous nipping. If this is severe (malignant/accelerated) hypertension, the disc will be swollen.
What if I’ve diagnosed it?
Manage blood pressure appropriately.
What will the hospital do?
Once the diagnosis is made, the patient will be referred to a physician for management of their hypertension.
What do I need to do?
Check renal function and monitor the blood pressure carefully. A swollen disc indicates severe hypertension and the risk of significant end organ compromise. Treat as appropriate.
What to tell the patient
Any visual loss may be reversible to some degree once their blood pressure is controlled and the retinal changes subside.