Vet’s 2025 Guide to Pannus in Dogs: Chronic Superficial Keratitis Explained👁️🩺 

By Dr. Duncan Houston BVSc

🐾 What Is Pannus?

Pannus, also known as chronic superficial keratitis (CSK), is a lifelong immune-mediated condition that affects a dog’s eyes—specifically, the cornea (the clear outer surface). This non-infectious disease gradually causes inflammation, blood vessel growth, pigment buildup, and eventually corneal scarring that can impair vision or lead to blindness if left untreated.

🧬 What Causes Pannus in Dogs?

Pannus is caused by the immune system mistakenly attacking the dog’s corneal tissue. While the exact reason isn’t fully known, genetics, environment, and UV light exposure play key roles.

📌 Contributing factors:

• Genetics: Inherited tendency, especially in certain breeds.
• UV radiation: High exposure to sunlight increases severity.
• High altitudes: More UV rays in mountainous areas worsen inflammation.
• Air pollution or smoke: May aggravate or trigger symptoms.

🐶 Breeds Most at Risk

Pannus is particularly common in:

• German Shepherds 🇩🇪
• Belgian Tervurens 🇧🇪
• Greyhounds 🐾
• Siberian Huskies ❄️
• Border Collies 🐕
• Australian Shepherds 🇦🇺

👁️ Clinical Signs of Pannus

Symptoms often start subtly but worsen without treatment. They typically affect both eyes, though not always symmetrically.

🕵️ Early signs:

• Pink, raised lesion on the outer corner of the eye
• Small blood vessels creeping into the clear cornea
• Grey or hazy areas over the eye

⚠️ Progressing signs:

• Corneal pigmentation (brown or black coloration)
• Scarring or vision loss
• Discharge, squinting, pawing at the eye
• Thickened third eyelid or conjunctival swelling

Note: Pannus is not painful in the early stages but can become irritating if advanced or infected.

🔬 How Is Pannus Diagnosed?

Your veterinarian will usually diagnose pannus with a combination of clinical signs and a detailed eye exam. Additional diagnostics help rule out other conditions:

• Ophthalmic exam: To check corneal clarity, blood vessels, pigmentation.
• Fluorescein stain: Rules out ulcers.
• Schirmer tear test: Ensures tear production is normal.
• Intraocular pressure: To rule out glaucoma.

If needed, a referral to a veterinary ophthalmologist can confirm the diagnosis with imaging or cytology.

💊 Treatment Options in 2025

Pannus is not curable—but it is very manageable with lifelong medication and care. The goal is to control inflammation, prevent progression, and preserve vision.

🚨 First-Line Medications:

• Topical corticosteroids: e.g., Prednisolone acetate, dexamethasone drops
• Topical immunosuppressants: e.g., Cyclosporine (Optimmune), Tacrolimus

Most dogs require daily drops—sometimes multiple times per day at first, tapering to a maintenance schedule.

💉 Advanced & Adjunct Therapies:

• Subconjunctival steroid injections: Used during flare-ups
• Radiation therapy: e.g., strontium-90 for severe cases
• Cryotherapy: Used rarely to reduce scar tissue
• Surgical keratectomy: For thickened, scarred corneas

🕶️ Environmental Management:

• Reduce UV exposure (avoid midday sun)
• Use dog sunglasses like RexSpecs for outdoor play
• Indoor play or shaded walks during peak sun hours

📆 Lifelong Management Plan

Managing pannus requires consistency and dedication. Dogs typically stay on immunosuppressants or steroids for life.

✅ Maintenance Checklist:

• Daily or twice-daily eye drops 💧
• Regular rechecks with your vet 👩⚕️
• Adjust meds seasonally—flare-ups may occur in spring/summer 🌞
• Monitor for cloudy eyes, pigment, or squinting 👁️

📱 Ask A Vet Can Help:

• Get daily med reminders 💊
• Send eye photos for monitoring 📷
• Talk to a vet anytime about new symptoms 🩺

📊 Prognosis

With proper treatment, most dogs retain good vision and enjoy a full, happy life 🐕❤️. Uncontrolled