title: Hydrogel intracorneal lenses in aphakic eyes.
abstract: BACKGROUND
  The theoretical benefits of synthetic keratophakia over conventional corneal lamellar procedures are the elimination of donor concerns and superior refractive predictability. Additionally, synthetic material can be inspected for optical quality and power, and it can be sterilized. Furthermore, visual recovery should be more rapid since epithelium is not removed from the central part of the cornea and the need for keratocyte repopulation is eliminated.
  
  
  OBJECTIVE
  To present results on patients who received an intracorneal implant (Kerato-Gel, Allergan Medical Optics, Irvine, Calif) that was made from lidofilcon A, a glucose-permeable hydrogel with an equilibrium water content of 68%.
  
  
  METHODS
  The intracorneal implants were implanted in 35 adult patients for correction of aphakia. Inclusion criteria excluded patients with aphakia who were candidates for intraocular lenses.
  
  
  RESULTS
  A total of 19 patients were followed up through 2 years postoperatively. For 16 patients with 2-year postoperative refractive data, the average spherical equivalent was -0.63 +/- 2.07 diopters (D). At 2 years, 88% of patients were within +/- 3.00 D of plano and 50% were within +/- 1.00 D. the mean change in Snellen's line for corrected visual acuity was -3.25 lines at 2 years for all patients and -2.0 lines for a subgroup of five patients who were free of vision-limiting preoperative disease.
  
  
  CONCLUSIONS
  Results suggest that this intracorneal implant is well tolerated by the cornea and can provide predictable refractive results in patients with high-risk aphakia. Limitations of the procedure are uneven microkeratome resections, loss of best-corrected visual acuity, and irregular astigmatism in some patients. Although these data show good evidence of biocompatibility of the implant material, technical surgical progress is needed to advance this procedure into clinical therapeutic practice.
authors.affiliation: Center for Eye Research, Harvard Medical School, Boston, Mass, USA.
authors.forename: R F
authors.initials: RF
authors.lastname: Steinert
authors.forename: B
authors.initials: B
authors.lastname: Storie
authors.forename: P
authors.initials: P
authors.lastname: Smith
authors.forename: M B
authors.initials: MB
authors.lastname: McDonald
authors.forename: G
authors.initials: G
authors.lastname: van Rij
authors.forename: L D
authors.initials: LD
authors.lastname: Bores
authors.forename: J P
authors.initials: JP
authors.lastname: Colin
authors.forename: D S
authors.initials: DS
authors.lastname: Durrie
authors.forename: C
authors.initials: C
authors.lastname: Kelley
authors.forename: F
authors.initials: F
authors.lastname: Price
authors.forename: C
authors.initials: C
authors.lastname: Rostron
authors.forename: G O
authors.initials: GO
authors.lastname: Waring
authors.forename: L T
authors.initials: LT
authors.lastname: Nordan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001036:Aphakia, Postcataract / Q000150:complications*; D001672:Biocompatible Materials; D002452:Cell Count; D003315:Cornea / Q000033:anatomy & histology; D003319:Corneal Stroma / Q000601:surgery*; D004728:Endothelium, Corneal / Q000166:cytology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols; D019736:Prostheses and Implants; D012030:Refractive Errors / Q000209:etiology; D054140:Refractive Surgical Procedures; D014792:Visual Acuity
chemical_list: D001672:Biocompatible Materials; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D011092:Polyethylene Glycols