Natural Remedies for Conjunctivitis in Dogs and Cats

I have an eight year old German Shepherd who has recently been diagnosed with pannus (it's a disease affecting the cornea and causing membranes to grow over the cornea). The vet first gave me an antibiotic/steroid eye drop. That worked for a while and made the pannus in the right eye recede. Then, in March the disease flared up in both eyes. They itched, had a yellow discharge, and membranes grew over both corneas. She is now virtually blind. I think that colloidal silver has helped to make the discharge run clear, but I am wondering if anyone has succeeded in reversing this.