Pannus is an inflammatory condition that affects dogs’ eyes, especially in German Shepherd dogs and German Shepherd mixes. Also called chronic superficial keratitis, it generally shows up in dogs between four and seven years old and is a life-long condition.
Though German Shepherds and their crosses are most often affected, other breeds that are commonly affected include:
• Siberian Huskies
• Border Collies
• English Springer Spaniels
• Cattle Dogs
Pannus is thought to be immune-mediated – meaning the body’s immune system over-reacts and starts attacking the body – but an exact underlying cause has not been found. One theory suggests that increased exposure to UV light may be to blame, and pannus is seen more commonly in higher altitudes, possibly due to the increased UV light present there. Once a dog presents with pannus, she will have it for the rest of her life.
The symptoms of pannus start off small and may be hard to notice. Generally, tiny vessels begin to grow on the cornea of both eyes and progress to large lesions. They tend to be raised and may also include dark pigmentation. Sometimes, thickening of the third eyelid is also seen. Without treatment, the lesions may eventually cover the entire cornea. The good news is that the condition is generally not painful.
Pannus cannot be cured, but it can be controlled with lifelong treatment. Most conditions are controlled quite well, with symptoms being stopped in their tracks once treatment is started. However, more severe cases are harder to control, as is the often the case when young German Shepherds present with the condition.
Treatment centers on suppression of the immune response in the eye and consists of daily topical medication. Cyclosporine or steroid drops are used several times a day when the condition is first noted, and then the frequency of application decreases over time until the lowest effective dose is found. The goal of treatment is to stop current lesions from growing larger.
Severe cases will require much more invasive procedures like steroid injections, radiation treatments and surgery, especially if blindness and corneal scarring have occurred.