title: 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.
abstract: 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.
authors.affiliation: Cornea Services, Narayana Nethralaya, Bangalore, India.
authors.forename: Mukesh
authors.initials: M
authors.lastname: Kumar
authors.forename: Rohit
authors.initials: R
authors.lastname: Shetty
authors.forename: Rajesh S
authors.initials: RS
authors.lastname: Kumar
authors.forename: Sriharsha
authors.initials: S
authors.lastname: Nagaraj
authors.forename: Bhujang
authors.initials: B
authors.lastname: Shetty
mesh_terms: D057128:Aberrometry; D003261:Contact Lenses; D003319:Corneal Stroma / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography; D057108:Corneal Wavefront Aberration / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology / Q000601:surgery*; D019736:Prostheses and Implants; D017755:Prosthesis Fitting; D019919:Prosthesis Implantation; D014786:Vision Disorders / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult