There are many reasons why cat’s eyes (pupils) dilate. This happens naturally as a response to the amount of light in their environment, due to fear or anxiety, or there can be a more sinister health reason.
Dr. Dubielzig says: “Although tumours of the eye and its supporting tissues in domestic animals are relatively rare, they assume an enhanced importance because of the visibility and effect on function of even small tumours within, or adjacent to, the eyes.”
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What Does It Mean When a Cat's Eyes Are Dilated
When a cat’s pupils dilate it can be due to danger, excitement, environmental factors, health problems or even head trauma. When it comes to your geriatric cat you may notice that his eyes are dilated for extended periods of time; and this could be a sign of an underlying age-related illness. It is of utmost importance to take your senior cat in for regular check-ups, there are various tests that your veterinarian will do to determine the health of your cat’s eyes and what may be the cause of their dilated pupils.
If you spend long periods of time away from home a Petcube Camera is a worthwhile investment to keep an eye on your cherished cat to see if their pupils are dilated for any extended period of time, or if only one is dilated at a time.
Dr. Dubielzig says “Cats with traumatic brain injuries may have a variety of clinical signs, ranging from minor neurological deficits to life-threatening neurological impairment. Appropriate management depends on prompt and accurate patient assessment, and an understanding of the pathophysiology of brain injury.”
One of My Cat's Eyes Is Dilated
What can be the cause of your cat only having one dilated pupil, otherwise known as anisocaria? There can be many reasons why your cat has unevenly dilated pupils, the list is exhaustive, but here are a few possible causes:
- Glaucoma (Increased intraocular pressure will result in widened pupils)
- Head trauma (Research has shown that symptoms can range from mild to life threatening)
- Toxin ingestion (Eating certain toxic plants)
- Corneal ulcers
- Ocular tumours (Tumours affecting the structure of the eye)
- Iris atrophy (Studies have shown that this usually happens unilaterally)
- Progressive Retinal Atrophy (The cells in the cats’ eyes weaken with age)
- Poor vision (Your cat’s vision can deteriorate with age)
- Hypertension (High blood pressure)
- Infectious diseases (For example feline herpes virus)
- Feline dysautonomia
- Inflammation in the eye
If your cat persistently has unevenly dilated or dilated pupils it is of utmost importance to take them to a veterinarian for a consultation. In these cases, it is very convenient already being signed up with an Emergency Fund.
Dr Ollivier says: “Bacterial corneal diseases in dogs and cats are most commonly considered in one of two categories—bacterial ulcerative keratitis and corneal abscesses. Ulcerative keratitis is frequent; it represents the most common ocular diseases in dogs and cats. Because some of these corneal ulcers can be very severe, progress rapidly, and therefore are sight threatening, the crucial steps of their diagnosis and management are stressed.”
Conclusion
It is always better to be safe than sorry when it comes to the health of your cat. Your cat should be taken to a veterinarian for a consultation immediately if persistently dilated or unevenly dilated pupils are witnessed.