title: Intrastromal femtosecond laser presbyopia correction: 1-year results of a multicenter study.
abstract: OBJECTIVE
  To investigate functional outcomes of the INTRACOR femtosecond laser-based intrastromal procedure to treat presbyopia.
  
  
  METHODS
  Sixty-three eyes from 63 presbyopic patients (median age: 54 years) with mild hyperopia were enrolled in this prospective, ethics committee-approved, multi-center, nonrandomized clinical trial. The INTRACOR procedure was performed using the Technolas femtosecond laser (Technolas Perfect Vision GmbH) in the nondominant eye. Postoperatively, follow-up was performed at 1 day, 1 week, and 1, 3, 6, and 12 months and included near and distance visual acuity tests, slit-lamp examinations, and corneal topography.
  
  
  RESULTS
  All 63 surgeries were uneventful. Twelve months postoperatively, outcomes of 58 (92.1%) eyes were available for evaluation. Median uncorrected distance visual acuity (0.1 logMAR [range: 0.5 to 0.0 preoperatively and 0.5 to -0.1 postoperatively]) and corrected distance visual acuity (CDVA) (0.0 logMAR [range: 0.2 to -0.2 preoperatively and 0.3 to -0.1 postoperatively]) remained stable. Median spherical equivalent changed from +0.63 diopters (D) preoperatively to 0.00 D postoperatively. Median uncorrected near visual acuity increased significantly from 0.7 logMAR (range: 1.0 to 0.2) preoperatively to 0.2 logMAR (range: 0.8 to -0.1) postoperatively and eyes gained a median of 4 lines (range: 1 to 9 lines). Losses of 2 lines of CDVA were noted in 7.1% of eyes. Ring cuts were faintly visible at 12 months.
  
  
  CONCLUSIONS
  The INTRACOR presbyopia procedure showed good and stable visual acuity outcomes over 12-month follow-up but loss of CDVA occurred in 7% of eyes. Overall patient satisfaction with the procedure was approximately 80%. Short treatment time and maintained corneal surface integrity are advantages of this procedure.
authors.affiliation: Internatioa Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, Germany. mike.holzer@med-heidelberg.de
authors.forename: Mike P
authors.initials: MP
authors.lastname: Holzer
authors.forename: Michael C
authors.initials: MC
authors.lastname: Knorz
authors.forename: Mark
authors.initials: M
authors.lastname: Tomalla
authors.forename: Tobias M
authors.initials: TM
authors.lastname: Neuhann
authors.forename: Gerd U
authors.initials: GU
authors.lastname: Auffarth
mesh_terms: D057128:Aberrometry; D000328:Adult; D000368:Aged; D003319:Corneal Stroma / Q000502:physiology / Q000601:surgery*; D019781:Corneal Topography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053685:Laser Therapy; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011305:Presbyopia / Q000503:physiopathology / Q000601:surgery*; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology