Recurrent Corneal Erosion //
When the corneal surface is injured a linear, round or oval defect is produced. The cells at the edge of the defect begin to multiply and migrate across the defect within hours of the injury. The first stage of repair (closure of the defect) may be completed in a period of 8-72 hours. Frequently the defect is said to have "healed" when closure is completed. Complete healing, however, requires both closure of the defect and the firm reattachment (second stage of repair) of the new cells to the underlying cornea. This second stage of repair may take 6-8 weeks or longer.
Poor or defective reattachment of new surface cells may lead to recurrent breakdown of the surface (typically in the same area) with strong blinking, eyelid rubbing or adhesion of the eyelids to the corneal surface during sleep. Irritation, tearing and pain of varying severity frequently results. Often these symptoms will occur during sleep or when the eyes are first opened in the morning. This is thought to relate to reduced tear production during sleep periods which gives the lid and ocular surface an opportunity to stick together. This problem is called a Recurrent Erosion Syndrome.
Surface trauma (from a fingernail, tree branch, etc.) and tiny, hereditary, irregularities in the surface layer of the cornea (wrinkles or microcysts) are the most frequent predisposing conditions. At times, there does not appear to be a preceding event or abnormal finding. When wrinkles or microcysts are found in both eyes an hereditary condition called Anterior Basement Membrane Dystropy or Map-Dot-Fingerprint Dystrophy is usually at fault.
Treatment goals are directed toward decreasing the incidence and severity of recurrent erosion episodes, and preventing development of secondary infection and scarring when an erosion occurs. The simplest treatment approach involves the use of lubricating drops during the day and ointment at nighttime to prevent the lid from sticking to the corneal surface. If the surface is loose, or folded and wrinkled, removal of the detached cells by gentle scrapping may be required to promote resurfacing of the cornea. Therapeutic bandage contact lenses may be used after an acute breakdown, after removal of loose or folded surface tissue, or in an attempt to protect the surface from breakdown after healing.
Treatment may take three to four months before the surface cells have developed a firm attachment to the underlying cornea. In recalcitrant cases, the loose and poorly attached surface cells may be gently removed and the underlying layer treated with a diamond burr or Excimer laser to establish a surface to which new epithelial cells will better attach. A procedure termed “stromal puncture” tries to create small scars that will better “anchor” the new cells upon healing. There procedures are usually performed in the office.