TL;DR: Most eyelid bumps in cats are cysts or tumors that require a veterinary exam within a few days to prevent eye irritation. Seek urgent care if your cat is squinting, pawing at the eye, or has yellow discharge.
What causes a bump to grow on my cat's eyelid?
A growth appearing on the margin (the edge) of your cat's eyelid is often related to the Meibomian glands, which produce the oily layer of the tear film. These growths can be benign tumors, cysts, or inflammatory reactions like a chalazion. While less common than in dogs, feline eyelid tumors can sometimes be more locally aggressive, making early identification important.
Is a bump on my cat's eyelid considered a medical emergency?
- The urgency level for an eyelid bump is typically medium, requiring a veterinary appointment within a few days.
- Urgency increases if you notice your cat squinting, tearing excessively, or producing yellow discharge.
- Immediate attention is needed if your cat is pawing at the eye or if the growth is rubbing against the eyeball.
- A growth that irritates the surface of the eye can quickly cause a painful corneal ulcer.
How does providing a photo help triage my cat's eyelid bump?
- A clear, high-resolution photo allows a professional to see the exact positioning of the mass.
- Visuals help determine if the bump is likely a fluid-filled cyst or a solid mass.
- A photo confirms whether the growth is currently touching the eyeball.
- This information is vital for deciding how quickly your cat needs to be seen and what diagnostic steps may be required.
Clinical Context (Merck Veterinary Manual)
In cats, eyelid masses are frequently malignant neoplasms, with squamous cell carcinomas being common, especially in white cats with non-pigmented eyelid margins. These tumors can appear as pink, roughened, irregular masses or thickened ulcerations. Other less frequent neoplasms include adenocarcinomas, fibrosarcomas, neurofibrosarcomas, and basal cell carcinomas. Localized eyelid margin inflammation, or blepharitis, can also cause bumps and may result from dermatophytes, Demodex, or bacterial infections such as staphylococci, potentially requiring skin scrapings, cultures, and biopsies for diagnosis. Anomalies of the cilia (distichiasis) can cause bumps, and treatment, such as cryotherapy, is indicated if corneal or conjunctival disease results.
Chapter: Oncology, Ophthalmology
Source: The Merck Veterinary Manual, 11th Edition (Page 518)