title: Visual outcomes after femtosecond-assisted intracorneal MyoRing implantation: 18 months of follow-up.
abstract: OBJECTIVE
  To determine the long-term results of femtosecond-assisted MyoRing implantation for the treatment of keratoconus.
  
  
  METHODS
  In this prospective, non-randomized, interventional clinical study, 47 eyes of 46 patients with keratoconus grade 1 to 3 entered the study. For all patients, a MyoRing (Dioptex, GmbH, Austria) was implanted using a femtosecond laser (Femto LDV, Ziemer, Germany).
  
  
  RESULTS
  At 18 months, mean uncorrected and best corrected visual acuity was 0.41 ± 0.19 logMAR, (P = 0.004) and 0.62 ± 0.22 logMAR (P < 0.001), and mean manifest refraction spherical equivalent was -0.38 ± 2.62D (P < 0.001). The central 3-mm maximum and mean keratometry decreased by 5.20 ± 3.06D and 4.77 ± 2.47D, respectively (both P < 0.001), and the 8-mm maximum keratometry decreased by 1.16 ± 5.50D (P = 0.185). Central and minimal corneal thickness showed an insignificant increase. Both corneal hysteresis and corneal resistance factor showed an insignificant decrease of about 0.13 mmHg. Endothelial cell count decreased by 215.43 ± 300.55 cell/mm(2) (P < 0.001). Twenty-six subjects (55.3 %) had halo vision at night and 24 subjects (51.1 %) had glare at night.
  
  
  CONCLUSIONS
  Femtosecond-assisted intracorneal MyoRing implantation can be an appropriate treatment option in keratoconus patients with central corneal protrusion, but the incidence of optical disturbances can be relatively high.
authors.affiliation: Noor Ophthalmology Research Center, Noor Eye Hospital, No. 96 Esfandiar Blvd., Vali'asr Ave, Tehran, Iran.
authors.forename: Masoomeh
authors.initials: M
authors.lastname: Mohebbi
authors.affiliation: Noor Ophthalmology Research Center, Noor Eye Hospital, No. 96 Esfandiar Blvd., Vali'asr Ave, Tehran, Iran. hhashemi@norc.ac.ir.
authors.forename: Hassan
authors.initials: H
authors.lastname: Hashemi
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Soheila
authors.initials: S
authors.lastname: Asgari
authors.affiliation: Noor Ophthalmology Research Center, Noor Eye Hospital, No. 96 Esfandiar Blvd., Vali'asr Ave, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Bigdeli
authors.affiliation: Farabi Eye Hospital, Department of Ophthalmology, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Kambiz Ameli
authors.initials: KA
authors.lastname: Zamani
mesh_terms: D000328:Adult; D002452:Cell Count; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D055954:Corneal Endothelial Cell Loss / Q000175:diagnosis / Q000209:etiology; D019781:Corneal Topography; D004728:Endothelium, Corneal / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology / Q000601:surgery*; D053685:Laser Therapy; D008297:Male; D065228:Non-Randomized Controlled Trials as Topic; D011183:Postoperative Complications; D011446:Prospective Studies; D019919:Prosthesis Implantation / Q000379:methods; D012029:Refraction, Ocular / Q000502:physiology; D014786:Vision Disorders / Q000175:diagnosis / Q000209:etiology; D014792:Visual Acuity / Q000502:physiology*; D055815:Young Adult
keywords: Continuous ring; Femtosecond laser; Keratoconus; MyoRing