A GREAT deal of difficulty has been encountered in verifying the vertex power of flexible contact lenses by conventional technique. This problem is related to the flexibility and hydration of the lens.
Refractive keratoplasty includes the separation of a corneal disc from the body of the cornea. We, in an attempt to verify vertex power of this section, have encountered the same verification difficulties presented by flexible contact lenses. The solution of this problem has been the adaptation of a contact lens technique originated at the Institute of Macromolecular Chemistry of the Czechoslovak Academy of Science.
A soft-lens centrifuge was designed to solve this problem. Figure 1 shows two brass fittings, two nylon covers, and one polymethyl methacrylate contact lens with a flat peripheral lip. The hard lens was manufactured in a series of different radii, each lens having a paraxial vertex power of zero.The hard lens, with
Kaplan MM, Elstein JK, Sehgal VN, Katzin HM. Corneal Section Verification in Refractive Keratoplasty. Arch Ophthalmol. 1968;79(1):16-17. doi:10.1001/archopht.1968.03850040018006