As a rough guide, a non-infected ulcer can be expected to heal at approximately 0.6mm/day. Complications
In cases where the ulcer is not healing:

Is there a persistent source of irritation? Foreign body
Self traumatisation
Iatrogenic. Is it infected? Review antibiotic therapy
C+S if not already performed. Immunosuppression? Cushings
Steroid therapy. Compliance? Is what youve prescribed getting onto the eye? None of the above? Abnormal epithelium may have formed, keratectomy may be appropriate.Melting ulcers reflect inappropriate collagenolysis of the corneal stroma, by matrix-metalloproteinases (MMPs). Bacterial pathogens (especially Pseudomonas and β-haemolytic Streptococcus) induce the corneal epithelial cells and resident leucocytes to upregulate pro-inflammatory, and MMP-activating cytokines (IL-1,-6 and -8). These bacteria can also produce their own proteinases. The combination of exogenous, and upregulated endogenous, proteinases leads to a rapid breakdown of collagen, with the characteristic melting appearance. Untreated this can lead to perforation within 12 hours (so act hard and fast!). There are several therapeutic options for inhibiting MMPs:

Autogenous serum – administer topically as often as possible. Keep refrigerated and change every 8 days. EDTA  - 0.05% q1h
Acetylcysteine – 5-10% q1h
Tetracyclines – Doxycycline especially has been shown to have anti-MMP effects
Tetanus antitoxin – can be delivered sub-conjunctivally. Contains macroglobulins with anti-collagenase effects.A combination of the above may be necessary early in the disease course. Effective antibiosis is also paramount, and gentamicin is a good empirical choice (although there are some reports of gentamicin-resistant Pseudomonas species). Obviously, treating an eye this frequently in practice will be difficult, so referral is probably the best option. See also
Corneal abrasion
Keratitis


== References ==
Pegylated interferon alfa-2a, sold under the brand name Pegasys among others, is medication used to treat hepatitis C and hepatitis B. For hepatitis C it is typically used together with ribavirin and cure rates are between 24 and 92%. For hepatitis B it may be used alone. It is given by injection under the skin.Side effects are common. They may include headache, feeling tired, depression, trouble sleeping, hair loss, nausea, pain at the site of injection, and fever. Severe side effects may include psychosis, autoimmune disorders, blood clots, or infections. Use with ribavirin is not recommended during pregnancy. Pegylated interferon alfa-2a is in the alpha interferon family of medications. It is pegylated to protect the molecule from breakdown.Pegylated interferon alfa-2a was approved for medical use in the United States in 2002. It is on the World Health Organizations List of Essential Medicines. Medical uses
This drug is approved around the world for the treatment of chronic hepatitis C (including people with HIV co-infection, cirrhosis, normal levels of ALT) and has recently been approved (in the EU, U.S., China and many other countries) for the treatment of chronic hepatitis B. It is also used in the treatment of certain T-cell lymphomas, particularly mycosis fungoides. Peginterferon alfa-2a is a long acting interferon. Interferons are proteins released in the body in response to viral infections. Interferons are important for fighting viruses in the body, for regulating reproduction of cells, and for regulating the immune system.