Femtosecond laser correction of presbyopia (INTRACOR) in emmetropes using a modified pattern

J Refract Surg. 2012 Dec;28(12):872-8. doi: 10.3928/1081597X-20121115-03.

Abstract

Purpose: To evaluate functional results and corneal changes after femtosecond laser correction of presbyopia (INTRACOR, Technolas Perfect Vision GmbH) in emmetropes using a modified treatment pattern over a 12-month period.

Methods: Twenty eyes from 20 emmetropic patients were treated with a modified intrastromal INTRACOR pattern consisting of 5 central rings and 8 radial cuts in a prospective, nonrandomized, uncontrolled, open, single-center, clinical study. Refraction, visual acuity, endothelial cell density, corneal pachymetry, total corneal power, and stray light were evaluated preoperatively and 1 (except endothelial cell density and stray light), 3, 6, and 12 months postoperatively. Patients filled out a subjective questionnaire at 12 months postoperatively.

Results: Comparison of preoperative versus 12-month postoperative median values revealed a significant improvement in uncorrected near visual acuity (UNVA) from 0.60 (20/80) to 0.10 logMAR (20/25) (P<.0001) and a significant decrease in corrected distance visual acuity (CDVA) from -0.10 (20/16) to 0.00 logMAR (20/20), which equals a median loss of one line (P=.0005). Fifteen percent of patients lost two lines of CDVA in the treated eye. Subjective spherical equivalent refraction remained unchanged at 0.00 diopters (D) (P=.194). After INTRACOR treatment, significant corneal steepening of 1.40 D and midperipheral flattening of 0.50 D occurred (both P<.0001). Corneal pachymetry at the thinnest point and endothelial cell density did not change significantly (P=.829 and P=.058, respectively).

Conclusions: After 12 months, the modified INTRACOR pattern improved UNVA in emmetropic patients without inducing a myopic shift or significant changes in endothelial cell density or pachymetry.

Publication types

  • Clinical Trial

MeSH terms

  • Aberrometry
  • Aged
  • Cell Count
  • Corneal Pachymetry
  • Corneal Stroma / surgery*
  • Corneal Wavefront Aberration / physiopathology*
  • Emmetropia / physiology*
  • Endothelium, Corneal / pathology
  • Female
  • Humans
  • Laser Therapy / methods*
  • Light
  • Male
  • Middle Aged
  • Presbyopia / surgery*
  • Prospective Studies
  • Refraction, Ocular / physiology
  • Scattering, Radiation
  • Surveys and Questionnaires
  • Visual Acuity / physiology