New plastic operation for correcting the refractive error of aphakic eyes by changing the corneal curvature. Preliminary report.

THiE problem of correcting the refractive error of an aphakic eye other than by prescribing the cumbersome cataract lenses still remains open, in spite of the excellent work done in this field by Ridley, and all its modifications. In search of a method which might combine greater safety for the patient with a simpler operative technique, an operation has been devised which consists in implanting a small plastic lens or a lamellar corneal graft between the lamellae of the central part of the cornea to increase the refractive power of the eye. From the first stage of this enterprise, which comprised 52 experiments on rabbit eyes (Krwawicz, 1960), the following conclusions have been drawn: (1) Intracorneal implantation of a plastic lens changes the refraction of the eye. (2) After the implantation of the plastic lens the cornea heals without signs of irritation or reduction in clarity, but there is danger of a late reaction on the part-of the corneal tissue, which may cause opacification. (3) The refractive effect of the implanted lens continues even if the lens is removed after some days. This-can be explained by the fact that when the lens is introduced between the two layers of the split cornea, the anterior layer is displaced towards the centre of the cornea by the thickness of the lens. This dislocation is permanently fixed by the healing process, so that the cornea cannot regain its previous shape, even if the lens is removed. The gap between the two layers of the cornea which remains after the removal of the lens then fills with clear corneal tissue, and only a delicate, annular scar marks the place where the edge of the lens had rested. (4) Intracorneal implantation of a lamellar corneal graft distinctly changes the corneal curvature.