The normally white part of the eye (sclera) appears red (red eye) in cats
When to visit the vet?
Urgent see a veterinarian within 24 hours
Severe pain, sudden squinting/blepharospasm, corneal opacity, vision loss, pupil changes
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Definition
Can Occur with the Following Diseases:
- Blood in the Front Chamber of the Eye in Cats (Hyphema)
- Pus in the Front Chamber of the Eye in Cats (Hypopyon)
- Inflammation of the Outer Eye Layer in Cats (Episcleritis)
- Inflammation Inside the Eye in Cats (Uveitis)
- High Eye Pressure (Glaucoma) in Cats (Glaucoma)
- Eosinophilic Corneal Inflammation in Cats (Feline Eosinophilic Keratitis)
- Eye Bulging Out of the Socket in Cats (Proptosis)
- Iris Adhesions in Cats (Posterior Synechiae)
Basics and possible causes
The redness of the sclera in cats can be caused by various factors. One of the most common causes is conjunctivitis, which is an inflammatory condition of the conjunctiva of the eye. This can be triggered by bacteria, viruses, allergies, or foreign bodies in the eye. Viral conjunctivitis is often caused by Feline Herpesvirus, while bacterial infections are frequently caused by Chlamydia or Mycoplasma.
Another cause of a red eye can be episcleritis, an inflammatory condition of the outer layer of the sclera, which can arise from autoimmune diseases or infections. Glaucoma, a disease characterized by increased intraocular pressure, can also lead to redness of the eyes. This condition is particularly dangerous as it can lead to permanent damage or blindness if left untreated.
Traumatic injuries, such as scratches or impacts, can also lead to redness. Such injuries can result from fights with other animals or household accidents. Allergic reactions to dust, pollen, or certain foods can also cause redness of the eyes, often accompanied by itching.
In rare cases, a red eye can indicate more serious systemic diseases such as high blood pressure, blood clotting disorders, or tumors. These causes are less common, but they emphasize the importance of a thorough examination by a veterinarian.
Typical accompanying symptoms
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Eye discharge: In addition to redness, there may be clear, yellow, or green discharge, indicating an infection.
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Swelling: The tissues around the eye can swell, making the eye appear as if it is sunken deeper into the orbital cavity or bulging.
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Itching: The cat may frequently rub its eyes with its paws or rub its head on furniture or carpets, which indicates itching.
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Tearing: Excessive tearing can occur, especially with allergic reactions or irritation from foreign bodies.
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Behavioral changes: The cat may appear lethargic, lose its appetite, or hide, which indicates discomfort.
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Sensitivity to light: In some cases, the cat may become sensitive to light and try to stay away from bright environments.
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Vision problems: In severe cases, the cat may show visual impairments, such as bumping into objects or having difficulty catching prey.
When to visit the vet?
It is important to see a veterinarian if the redness of the eye lasts longer than one to two days or is accompanied by other symptoms such as discharge, swelling or behavioral changes. Symptoms such as severe swelling, significant pain, or signs of vision loss are particularly concerning, as these may indicate more serious problems.
Also, if the cat shows signs of pain, such as frequent blinking, rubbing of the eyes, or avoidance of touch near the head, a veterinarian should be consulted as soon as possible. Special caution should be exercised in cats with known pre-existing conditions such as diabetes or high blood pressure, as these conditions can make the eyes more susceptible to problems.
A visit to the veterinarian is also advisable if the cat has recently been involved in a fight or suffered an injury, as even small injuries can lead to serious infections.
Symptom recognition for animal owners and veterinary diagnostic procedures
Pet owners should regularly check their cats’ eyes for changes. A red eye is often easy to recognize, but accompanying symptoms such as discharge or swelling require closer observation. It is helpful to keep the cat calm in a well-lit room to inspect the eye closely.
The veterinarian will conduct a thorough examination, which includes a medical history and a physical inspection of the eye. The use of an ophthalmoscope allows the veterinarian to examine the inside of the eye closely and detect signs of injury or inflammatory conditions.
Additional tests may be necessary to determine the exact cause. These include a Schirmer tear test to measure tear production, a fluorescein test to detect corneal injuries, and possibly blood tests to rule out systemic diseases.
What can pet owners do and professional therapy options
Until the vet visit, pet owners should make sure that the cat does not rub its eyes. It may be helpful to trim the cat’s claws to minimize damage from scratching. A clean environment, free of dust or other irritants, can also help to relieve symptoms.
If the cat has discharge, the eye can be gently cleaned with a soft, damp cloth to remove crusts. Care should be taken to use only clean water or a solution recommended by the veterinarian to avoid further irritation.
Avoiding stress and providing a quiet place to rest can also help promote healing. If an allergic reaction is suspected, potential allergens should be identified and avoided until an accurate diagnosis can be made.
Outlook on current research
Current research in veterinary medicine focuses on better understanding the causes and mechanisms that trigger red eye in cats. Researchers are investigating the role of inflammatory processes and immunological reactions that can lead to redness of the sclera. It is being investigated how environmental factors, genetic predispositions, and a cat’s general health can influence the occurrence of this symptom.
Another focus of research is on developing new diagnostic methods to identify the underlying causes of red eye in cats more quickly and precisely. Potential applications of imaging techniques such as optical coherence tomography (OCT) are being explored to gain detailed insights into the structure of the eye and possible changes. These techniques could revolutionize the diagnosis and management of eye diseases in cats in the future.
In addition, studies are investigating innovative therapy approaches for red eye in cats. Researchers are working on developing new medications that specifically target inflammatory reactions in the eye to alleviate symptoms and promote healing. Biotechnological approaches, such as the use of monoclonal antibodies, are also being explored to block specific molecular targets in the inflammatory process.
Behavioral research is investigating how stress and psychological factors can influence the occurrence and intensity of red eye in cats. These studies could lead to a better understanding of how the well-being and living conditions of animals can be improved to reduce eye symptoms. Overall, the research aims to develop more comprehensive and individualized therapy strategies that improve the long-term well-being of cats.