title: Fitting the post-keratoplasty cornea with hydrogel lenses.
abstract: OBJECTIVE
  We report two cases who have undergone penetrating keratoplasty (three eyes total), and who were fitted with hydrogel lenses.
  
  
  METHODS
  In the first case, a 28-year-old male presented with an interest in contact lens fitting. He had undergone corneal transplantation in both eyes, about 5 years ago. After topographies and trial fitting were performed, it was decided to be fitted with reverse geometry hydrogel lenses, due to the globular geometry of the cornea, the resultant instability of RGPs, and personal preference. In the second case, a 26-year-old female who had also penetrating keratoplasty was fitted with a hydrogel toric lens of high cylinder in the right eye.
  
  
  RESULTS
  The final hydrogel lenses for the first subject incorporated a custom tricurve design, in which the second curve was steeper than the base curve and the third curve flatter than the second but still steeper than the first. Visual acuity was 6/7.5 RE and a mediocre 6/15 LE (OU 6/7.5). The second subject achieved 6/4.5 acuity RE with the high cylinder hydrogel toric lens.
  
  
  CONCLUSIONS
  In corneas exhibiting extreme protrusion, such as keratoglobus and some cases after penetrating keratoplasty, curvatures are so extreme and the cornea so globular leading to specific fitting options: sclerals, small diameter RGPs and reverse geometry hydrogel lenses, in order to improve lens and optical stability. In selected cases such as the above, large diameter inverse geometry RGP may be fitted only if the eyelid shape and tension permits so. The first case demonstrates that the option of hydrogel lenses is viable when the patient has no interest in RGPs and in certain cases can improve vision to satisfactory levels. In other cases, graft toricity might be so high that the practitioner will need to employ hydrogel torics with large amounts of cylinder in order to correct vision. In such cases, the patient should be closely monitored in order to avoid complications from hypoxia.
authors: Eyeart contact lens fitting centres, Thessaloniki, Greece. info@eyeart.gr
authors: Costas
authors: C
authors: Katsoulos
authors: Vasileiou
authors: V
authors: Nick
authors: Karageorgiadis
authors: K
authors: Lefteris
authors: Mousafeiropoulos
authors: M
authors: Theodore
mesh_terms: D000328:Adult; D003262:Contact Lenses, Extended-Wear; D003315:Cornea / Q000473:pathology; D019781:Corneal Topography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D007640:Keratoconus / Q000473:pathology / Q000601:surgery*; D015948:Keratoplasty, Penetrating / Q000379:methods*; D008297:Male; D011182:Postoperative Care / Q000379:methods*; D017755:Prosthesis Fitting / Q000379:methods*; D014792:Visual Acuity
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate