Pannus (Chronic Superficial Keratitis)
Learn what the condition is, how it may be detected early, how it is treated or managed, and which breeds or species are linked to it.
Condition snapshot
A concise guide to the condition’s pattern, detection, management and urgency.
This snapshot is a general guide, not a diagnosis or treatment plan. New, severe or worsening signs require veterinary assessment.
About the condition
Pannus, or chronic superficial keratitis, is an immune-mediated inflammatory disease of the cornea. German Shepherd Dogs and related breeds are particularly predisposed, although other dogs can be affected. Genetic susceptibility interacts strongly with ultraviolet-light exposure, which is why disease can be more severe in dogs living at high altitude or in regions with intense sunlight.
Inflammation usually begins at the outer edge of the cornea, often in the lower or lateral quadrant. Small blood vessels grow across the normally clear surface, followed by pink inflammatory tissue and dark pigment. Both eyes are generally affected, although severity may differ. A related inflammatory change can involve the third eyelid.
Early disease may cause little obvious pain, so owners first notice a hazy area, redness or pigment creeping across the cornea. If inflammation continues untreated, scar tissue and pigment can cover a large part of the visual axis and progressively reduce sight. Unlike an acute ulcer, pannus is usually a chronic process rather than a sudden painful injury.
Pannus does not have a short curative treatment. The immune response can be controlled, but the tendency persists for life. Early therapy is valuable because existing dense pigment and scar tissue may not fully disappear even after inflammation has been stopped. Protecting the clear central cornea before it becomes involved gives the best chance of preserving vision.
The condition is chronic rather than a one-off eye infection. The amount of active inflammation can wax and wane with season, ultraviolet exposure and treatment, so changes in the corneal surface over time are more informative than a single snapshot of redness or pigmentation.
Inspect the eyes for a new pink or reddish area near the outer corneal margin, increasing brown-black pigment, persistent haze or changes affecting both eyes. A normal eye at one age also does not guarantee lifelong freedom from disease because pannus can develop later.
Screening & Early Detection
Regular eye examination is the most useful early-detection strategy in predisposed breeds. Annual checks from young adulthood are reasonable, with closer review in dogs living in high-UV environments or from strongly affected family lines. A veterinarian can identify early blood-vessel growth or superficial pigment before vision is noticeably affected.
Because early pannus may not be painful, absence of squinting does not mean the cornea is normal.
A veterinary ophthalmologist can distinguish pannus from corneal degeneration, chronic ulceration, dry eye and other inflammatory diseases. Tear testing and fluorescein staining may be performed when concurrent surface disease is possible. Photographs can document the extent of pigment and vessels for comparison at future visits.
There is no routine DNA test that replaces clinical examination.
Early detection matters because medication is more successful at preserving clear cornea than at reversing heavy established scarring. Owners in sunny climates should be particularly vigilant and should not wait until the dog is bumping into objects before seeking an eye examination.
Diagnosis is made by ophthalmic examination based on the characteristic breed, distribution and appearance. A veterinary ophthalmologist may be consulted to confirm the diagnosis and exclude conditions such as corneal dystrophy, infection, dry eye or tumour. Cytology or biopsy is rarely needed in a typical case.
Treatment & Management
Treatment suppresses the abnormal immune response in the cornea and is usually required for life. Topical corticosteroid drops or ointment are commonly used to reduce inflammation rapidly, often combined with or followed by immune-modulating medication such as ciclosporin or tacrolimus. The intensity of treatment is reduced once disease is controlled but generally not stopped completely.
Eye medication schedules are adjusted according to the amount of active blood-vessel growth, redness and pigment. Long-term steroid use requires veterinary monitoring because steroids can worsen infection or corneal ulcers and can contribute to other ocular complications. Any sudden squinting or pain should therefore be assessed before simply increasing drops.
Reducing ultraviolet exposure can help limit flare-ups. Dog-specific protective goggles may be useful for dogs that tolerate them, and avoiding prolonged outdoor exposure during the most intense sunlight can complement medication. UV management is supportive rather than a substitute for immune therapy.
Established pigment and scar tissue may lighten but often does not disappear completely. In advanced cases, surgical removal of superficial pigment has been attempted, but recurrence is likely unless immune control continues.
Most dogs maintain useful vision when treatment begins early and owners apply medication consistently. Relapse commonly follows missed or discontinued treatment, so pannus should be viewed as a chronic controlled disease rather than one that is cured when the eye first looks clear again.
Breeds or species affected
Airedale Terrier
Open dog breed description, care requirements and conditions
Australian shepherd
Open dog breed description, care requirements and conditions
Belgian Shepherd Dog (Groenendael)
Open dog breed description, care requirements and conditions
Border Collie
Open dog breed description, care requirements and conditions
Dachshund
Open dog breed description, care requirements and conditions
Dalmatian
Open dog breed description, care requirements and conditions
English Pointer
Open dog breed description, care requirements and conditions
German shepherd
Open dog breed description, care requirements and conditions
Greyhound
Open dog breed description, care requirements and conditions
Lowchen
Open dog breed description, care requirements and conditions
Miniature Pinscher
Open dog breed description, care requirements and conditions
Siberian husky
Open dog breed description, care requirements and conditions
Tibetan spaniel
Open dog breed description, care requirements and conditions