Use of Wavefront Imaging Technology to Demonstrate Improvement in Corneal Aberrations Using Piggyback Contact Lens in a Keratoconus Eye With Intrastromal Corneal Ring Segment Implantation: A Case Report

Objective: To quantify short-term changes in corneal high-order aberrations (HOA) with piggyback contact lens use in an eye with keratoconus that had undergone intrastromal ring segment (Intacs) implantation. Methods: A patient with keratoconus reporting of distorted images after Intacs surgery was found to have HOA (trefoil, point spread function [PSF], and modulation transfer function [MTF]) as measured using wavefront technology (Nidek OPD-Scan III) and evidenced by her cylindrical correction. She underwent piggyback contact lens (silicone hydrogel and fluoroperm rigid gas-permeable lenses) fitting in an attempt to improve the HOA. Results: After piggyback contact lens fitting, her visual acuity improved and all her visual symptoms resolved. High-order aberrations reduced from 3.152 to 0.490 after the lens fitting and was noted to be 0.447 at 6 months; trefoil also significantly improved (0.360-0.096; it was 0.031 at 6 months). The cylinder decreased from -4.50 to -0.75 and was stable at 6 months (-1.00). There was also significant improvement in PSF and MTF. Conclusions: Visual acuity and symptoms along with HOA and cylinder improved after fitting of piggyback contact lens in our patient with keratoconus who had undergone Intacs.