title: Femtosecond laser-assisted MyoRing implantation in postoperative LASIK ectasia.
abstract: OBJECTIVE
  To evaluate the effect of MyoRing implantations (DIOPTEX GmbH, Linz, Austria) in patients with ectasia after LASIK.
  
  
  METHODS
  MyoRing implantation was performed in 15 eyes of 14 patients with ectasia after LASIK using a femtosecond laser. Uncorrected and corrected distance visual acuity, refraction, keratometry, central corneal thickness, corneal biomechanical profile, and corneal aberrometry were evaluated preoperatively and at 1, 3, and 6 months, and 1 year postoperatively.
  
  
  RESULTS
  Uncorrected distance visual acuity (1.02 ± 0.48 to 0.30 ± 0.18 logMAR), maximum keratometry (50.14 ± 1.82 to 43.80 ± 1.21 diopters), and sphere (-4.4 ± 4.8 to +1.50 ± 0.61 diopters) were significantly improved from preoperative values at 1 month after surgery with no significant change afterward. Corrected distance visual acuity did not improve significantly 1 month after implantation, but between the 1- and 3-month follow-up visits, a significant improvement (0.30 ± 0.1 to 0.17 ± 0.13 logMAR) was observed without any additional improvement thereafter. A nearly significant (P = .05) increase in central corneal thickness (439.4 ± 19 to 452.2 ± 20 μm) was observed during the 1-month postoperative period. Primary coma, higher-order aberrations, and trefoil showed an insignificant decrease 1 month after surgery and afterward. Spherical aberration significantly increased between the preoperative visit and the first postoperative visit. Corneal hysteresis and corneal resistance factor showed no significant change between visits.
  
  
  CONCLUSIONS
  MyoRing is a safe and effective method in patients with ectasia after LASIK. It can improve corrected distance visual acuity and reduce refractive error in these patients.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Jabbarvand
authors.forename: Mohammadnaser
authors.initials: M
authors.lastname: Hashemian
authors.forename: Hesam
authors.initials: H
authors.lastname: Hashemian
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Bazvand
authors.forename: Mehdi
authors.initials: M
authors.lastname: Khodaparast
mesh_terms: D057128:Aberrometry; D000328:Adult; D063171:Corneal Pachymetry; D004108:Dilatation, Pathologic / Q000601:surgery; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000009:adverse effects*; D054018:Lasers, Excimer; D008297:Male; D009216:Myopia / Q000601:surgery*; D011183:Postoperative Complications / Q000601:surgery*; D011446:Prospective Studies; D019919:Prosthesis Implantation; D012029:Refraction, Ocular / Q000502:physiology; D013524:Surgical Flaps; D014786:Vision Disorders / Q000534:rehabilitation*; D014792:Visual Acuity / Q000502:physiology