Glues similar to those used by many home handymen are being used in surgical techniques that have saved untold numbers of eyes from blindness.
Dr. Corey A. Miller, a Salt Lake ophthalmologist who specializes in corneal and external eye diseases, said the adhesive he uses is very much like such commercial products as Crazy Glue and Super Glue. The medical grade adhesive is a cleaned-up, sterile version of the over-the-counter glue.Eye surgeons have been using the cyanoacrylate adhesives since 1963, but the glue is still considered experimental in the United States. That's because the federal Food and Drug Administration has not officially approved its medical use.
That hasn't stopped medical eye specialists who have been experimenting for 20 years with the glue, and since the mid-1960s have documented its value in scientific medical journals.
Miller uses the glue to repair holes in the cornea, the clear window at the front of the eye. This thin, transparent tissue is easily perforated by injury, corrosive chemicals, inflammation or infection.
An eye can be saved by as little as one drop of the plastic glue, which, said Miller, does four things at once:
-It plugs the hole in the cornea and holds everything in place as it gives the corneal tissue a chance to heal.
-It promotes the growth of new blood vessels to the edge of the cornea (hich itself has no blood vessels), thus helping in the healing process.
-It keeps out inflammatory cells, which can release enzymes that literally cause the cornea to melt.
-It fights infection.
Miller said he routinely applies the glue in emergencies, even when he is not sure of the cause of the hole in the cornea and even before thinning of the cornea has resulted in a perforation. Even as a temporary procedure, the glue can save vision by preventing the hole from enlarging, keeping eye contents in and keeping germs out.
The glue works best in repairing small holes, only 2 to 3 millimeters (bout a tenth of an inch) across. In emergencies the trick is to prevent the hole from enlarging, especially in a process known as "corneal melting."
Corneal melting, the literal melting away of the cornea, occurs when tears dry up, when corrosive chemicals such as acid or alkali splash on the eye and cause significant damage or when the tissue is attacked by enzymes from inflammatory cells.
Miller said gluing is a temporary measure that is followed by more permanent repair such as a corneal graft or transplant. The glue is not a cure-all.
Restoration of vision is not instantaneous. The glue is clear and lets some light into the eye, but it is not transparent.
Because the glue has rough edges after it hardens, a soft contact lens is placed over it as a bandage to keep the glue in place and to prevent it from irritating the eyelid. As the tissue under it heals, the glue is slowly pushed forward.
Miller said that after a few days or weeks the glue falls off, leaving behind an area of healed corneal scar.
Despite the lack of an FDA stamp of approval, usage of the glue - imported from West Germany and Canada - is increasing. Miller said it is also being used by Utah ophthalmologists to temporarily close eyelids, as a patching measure.