Alloplastic Implants in Non-Human Primates

Abstract

Refractive corneal surgery has been under investigation for more than 30 years. Although several different surgical procedures have evolved, none has gained widespread popularity. Complex technology, slow visual recovery, and lack of predictability have been some of the major problems. In an attempt to overcome these difficulties, the feasibility of corneal implants made of alloplastic materials has been tested. This paper documents the successful use of high-water content hydro-gels in non-human primates. Although these materials appear to be biologically compatible with corneal stroma, it was found that their position within the cornea was critical. Placement of these lenses at less than 50% corneal depth was universally unsuccessful, whereas placement at 50% or deeper was successful in all cases. Although stability of these materials within the cornea seems likely, the ultimate usefulness of the technique will depend on the ability to generate a predictable change in curvature at the anterior corneal surface