By Dr Duncan Houston
A cat that suddenly bumps into furniture or has persistently wide pupils may have a problem at the back of the eye. Retinal bleeding can be invisible to an owner until vision changes.
Finding the reason for the bleeding matters for the whole cat, not only the eyes. Some causes can also affect the kidneys, brain or circulation.
Quick Answer
Retinal haemorrhage means bleeding within or around the light-sensitive tissue at the back of the eye. High blood pressure is an important cause in cats, although inflammation, trauma and blood disorders are also possible. Sudden vision loss needs urgent veterinary assessment today, even if the eye looks comfortable.
Why can the retina bleed?
Small retinal vessels can become damaged or leaky. Hypertension can cause haemorrhage, swelling and retinal detachment. Older cats and cats with kidney disease or hyperthyroidism deserve particular attention, but blood pressure still needs measurement rather than assumption.
Other explanations include clotting abnormalities, low platelet counts, inflammation and some cancers. A clinical review of feline hypertensive eye disease explains the variety of changes found during a retinal examination.
What does the examination involve?
The vet assesses vision and examines the front and back of both eyes. Blood seen in the front chamber is called hyphaema; it is not automatically retinal haemorrhage, although both can occur together.
Blood pressure is measured with attention to stress and technique. Repeat readings can help, but convincing eye damage should not be dismissed as a stress response. Blood and urine tests assess kidney function, thyroid status when indicated, platelets and other possible causes. Selected cats need clotting tests or imaging.
Can treatment restore sight?
Treatment targets the cause. A hypertensive cat usually needs blood-pressure medication and rechecks, alongside management of any underlying disease. The ISFM hypertension guidelines emphasise identifying and managing damage to organs such as the eyes.
Some cats regain useful vision after prompt treatment, including when a detached retina reattaches. Others have permanent damage. Surgery is not the routine treatment for retinal detachment caused by hypertension. Ongoing pressure control matters even if vision does not return.
How worried should you be?
| What you notice | Why it matters | What to do |
|---|---|---|
| Retinal bleeding found at a routine examination | Possible systemic illness despite normal behaviour | Follow the vet’s prompt blood-pressure and laboratory plan. |
| Sudden wide pupils, bumping into objects or reluctance to move | Possible acute loss of vision | Arrange urgent assessment today. |
| Vision change with seizures, collapse or severe weakness | Possible wider organ involvement | Seek emergency care now. |
What else could explain these signs?
Glaucoma, cataracts, retinal degeneration, optic nerve disease and neurological disorders can also impair sight. A photograph of the pupil cannot distinguish these conditions or measure blood pressure.
When is this an emergency?
Sudden blindness requires urgent assessment, including out-of-hours care if necessary. Seizures, collapse, a very painful eye or eye trauma makes immediate emergency care especially important. Keep your cat indoors and away from stairs while arranging transport.
What should you do next?
- Note when navigation or pupil changes began, and report changes in thirst, appetite, weight or medication.
- Keep furniture and essential resources in familiar positions; block falls and outdoor access.
- Give prescribed blood-pressure medicine consistently and attend the scheduled rechecks.
- Ask how the vet will monitor both the eyes and the disease responsible for the bleeding.
Common mistakes to avoid
- Waiting for redness or pain before seeking help for sudden blindness.
- Assuming all eye bleeding is caused by trauma.
- Stopping blood-pressure treatment when vision improves.
- Giving human eye drops or blood-pressure tablets without a prescription.
Prevention and ongoing care
Regular veterinary care, including blood-pressure assessment when appropriate for age and health, can identify hypertension before obvious blindness. This is particularly useful in cats with kidney or thyroid disease.
A cat with lasting vision loss can often adapt to a predictable indoor environment. Speak before touching, keep resources easy to find and introduce changes slowly.
Frequently asked questions
Can high blood pressure make a cat suddenly blind?
Yes. Retinal bleeding and detachment are recognised complications.
Will the blood be visible from outside the eye?
Not necessarily. Bleeding at the back of the eye may only be seen during a retinal examination.
Can vision return?
Sometimes, depending on the cause, duration and damage. Prompt treatment improves the opportunity to preserve remaining sight.
Does a detached retina always need surgery?
No. Hypertension-associated detachment is generally managed by treating the pressure and underlying condition, with eye specialist advice when needed.
A change in sight is a reason to act promptly, not a normal consequence of ageing. Examining the retina and measuring blood pressure can reveal a treatable problem before further damage occurs.
For more practical animal health information, explore ASK A VET™. If your animal has emergency signs, contact a veterinary clinic immediately.
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