Vet Guide to Collie Eye Anomaly in Dogs 2025 🐶👁️

By Dr. Duncan Houston BVSc

Collie Eye Anomaly (CEA) is a congenital, inherited eye disorder affecting Collies and related breeds. In this 2025 guide, I explain the genetic causes, typical eye abnormalities, diagnosis, lifelong management, and breeding considerations to support optimal canine eye health. 💡

📍 What Is Collie Eye Anomaly?

CEA (also called choroidal hypoplasia) is a congenital defect present at birth due to incomplete development of blood vessels beneath the retina.
The anomaly is bilateral but may affect each eye differently. It stems from an autosomal recessive gene mutation (in NHEJ1).
A range of abnormalities may occur: pale choroid, retinal folds, coloboma (retinal hole), retinal detachment, hemorrhage—severity varies.

⚠️ Which Breeds Are Affected?

Most common in Rough and Smooth Collies, Shetland Sheepdogs, Border Collies, Australian Shepherds, and Nova Scotia Duck Tolling Retrievers.

📝 Clinical Signs & Impact

Often mild—with no immediate vision issues—but colobomas or retinal detachment can cause sudden blindness.
Visible signs: microphthalmia (small eyes), enophthalmia (sunken eyes), vision impairment, bumping into objects.
Blindness is usually painless, though secondary glaucoma may develop, causing pain and requiring treatment.

🔬 Diagnosis & Screening

Ophthalmoscopic exam by 6–8 weeks reveals choroidal hypoplasia; beyond this “go‑normal” period, pigment can mask the lesion.
Veterinary ophthalmologists use dilated fundus exams to identify retinal changes like colobomas or hemorrhages.
Genetic testing (DNA swab) identifies carriers and affected dogs—important to guide breeding.

✅ Treatment & Management

No cure exists for CEA itself.
Laser surgery may prevent progression of early retinal detachment.
Supportive care for affected dogs includes monitoring for glaucoma or eye discomfort, adapting environment, and ensuring safety.

🧬 Breeding & Prevention

CEA is autosomal recessive—both parents must carry the gene for affected puppies.
Responsible breeding involves genetic testing and early eye exams to avoid breeding affected or carrier dogs together.
Selective breeding has reduced CEA prevalence over decades, though pigment can mask mild cases post‑puppyhood (“go‑normal”).

📊 Summary Table

Aspect	Description	Vet/Breeder Action
Choroidal Hypoplasia	Pale retina layer	Early eye exam at 6–8 wks
Coloboma/Detachment	Hole or flap ≥ vision risk	Monitor/surgery if early
Genetic Status	Clear, carrier, affected	DNA test before breeding
Vision Outcomes	Normal to blind	Adapt home; monitor comfort, eye health

✅ Vet Tips by Dr Duncan Houston BVSc

🔍 Perform ophthalmic exams at 6–8 weeks to detect early lesions before pigmentation masks them.
🧪 Use commercial DNA testing and screen breeding dogs to prevent passing on defective genes.
📆 Even asymptomatic dogs need annual eye checks to monitor for late-onset complications.
🏠 Make living environments safe and consistent to support dogs with visual impairment.

If your dog is of a Collie or herding breed and has atypical eyes or vision issues, schedule an evaluation via the AskAVet.com app.🐾❤️