Collie Eye Anomaly, Choroidal Hypoplasia, CEA

CEA can cause no observable visual impairment to complete blindness depending on the severity of the disease. Dogs with poor vision will often act hesitant on stairs, bump into doorways or walls, and be disoriented if furniture is moved.

CEA can be identified by an ophthalmologist when a puppy is 6-8 weeks of age. There are other genetic and environmental factors that likely contribute to the severity of the disease.

A consult with a veterinary ophthalmologist is the ideal way to diagnose CEA. When the specialist examines the back of the eye, they can visualize the thin, pale, and nearly transparent patches of the choroid. In severe cases, they can identify a coloboma, which is an outpouching of the retina.

There is no treatment for CEA, although surgical intervention can help mitigate the signs of the disease in severe cases. If surgery is not an option, lifestyle changes can be made to help blind dogs adapt to their condition. In mild cases no treatment is required.

Talk to your vet about your dog’s CEA result so you can work together to plan their ongoing care and monitoring.

Schedule regular eye exams with your vet or a veterinary ophthalmologist to monitor for changes or complications that could affect vision.

If your dog’s vision is affected, help them adjust by keeping furniture and routines consistent, using verbal cues, and keeping them on a leash in unfamiliar areas.

Products such as protective halos can also help dogs navigate safely if their vision declines.

This mutation was first identified in the Collie.

Penetrance: It is important to note that both mild and severe forms of CEA arise from the same autosomal recessive mutation in the NHEJ gene, and that dogs with mild CEA can produce pups with severe CEA.

Gene

NHEJ1 (Intron 4)

Inheritance type

recessive

Clinical category

Ophthalmologic

Citations

1. Parker et al 2007

• Australian Cattle Dog
• Australian Shepherd
• Australian Shepherd
• Bearded Collie
• Border Collie
• Boykin Spaniel
• Collie
• Collie (Scottish-Type)
• English Shepherd
• Hokkaido
• Australian Kelpie
• Koolie
• Lancashire Heeler
• Windsprite
• McNab
• Miniature/MAS-type Australian Shepherd
• Nova Scotia Duck Tolling Retriever
• Shetland Sheepdog
• Silken Windhound
• Stumpy Tail Cattle Dog
• Welsh Sheepdog