Pannus (Chronic Superficial Keratitis)

This is an immune mediated condition affecting the cornea or clear part of the eye. It occurs primarily in middle aged German Shepherd dogs.

What is the cause?

The cause is thought to be immune mediated. Factors such as increased ultraviolet light, altitude and smoke are thought to contribute and can exacerbate the condition.

Is it inherited?

It may be inherited recessively in German Shepherd dogs.

Are other breeds affected?

It has been reported in Greyhounds, Lurchers, Border Collies and Long Haired Dachshunds but can occur sporadically in any breed. By far the greatest preponderance is reported in the German Shepherd dog.

How is it diagnosed?

Diagnosis depends on the clinical signs.  Initially there is a non-painful, pink, fleshy, elevated mass on the cornea usually on the outer quadrant. Both eyes are affected but one is often initially worse than the other. The third eyelid (nictitating membrane) also appears thick and sore (a variation of pannus involves just the third eyelid and is called nictitans plasmacytic conjunctivitis). In more chronic cases dark pigmentation and scarring is apparent on the cornea and spreads upwards and inwards. In advanced cases there is visual impairment. Blindness will follow if not treated. Tests can be carried out to confirm the diagnosis.

"In advanced cases there is visual impairment. Blindness will follow if not treated."

What is the treatment?

Treatment involves the use of topical corticosteroids or immune modulating drugs. Antibiotics are sometimes also needed. Treatment has to be life long. It is important that instructions regarding medication are carefully followed. Any course must be completed as instructed. Once under control topical immune modifying drugs will often prevent recurrence but the ointment or drops need to be continued long term. Regular check ups and owner vigilance are imperative since the condition can relapse.

If corticosteroids do not work, can anything else be done?

In severe cases surgery is possible. However the majority of cases do respond to topical medication provided instructions are diligently followed.