title: Outcome of complete intrastromal ring implantation using femtosecond laser in pellucid marginal degeneration.
abstract: OBJECTIVE
  To evaluate the effect of complete intrastromal corneal ring implantations on patients with pellucid marginal degeneration (PMD).
  
  
  METHODS
  Prospective interventional case series.
  
  
  METHODS
  Thirty-three eyes with PMD were included into the study. After pocket creation with femtosecond laser (Femtec; 20/10 PerfectVision), MyoRing implantation was performed. Uncorrected and corrected distance visual acuity (UDVA, CDVA), subjective refraction, keratometry, central corneal thickness, corneal biomechanical profile (Ocular Response Analysis), and whole-eye wavefront aberrometry (iTrace) were evaluated preoperatively and also postoperatively, 1 month, 3 months, 6 months, and 1 year after the operation.
  
  
  RESULTS
  One month after surgery, significant improvements were observed in UDVA (ANOVA; P=0.02), mean keratometry, sphere (ANOVA; P <0.001), and cylinder (ANOVA; P=0.04) with no significant changes afterwards. No significant change occurred in the corneal biomechanical profile. Primary coma and trefoil reduced after 1 year (ANOVA; P values were 0.02 and 0.06, respectively). Primary spherical aberration significantly increased according to the 1-year follow-up (ANOVA; P<0.001). No significant complication was observed.
  
  
  CONCLUSIONS
  MyoRing is considered as a treatment modality for spherocylindrical correction in patients with PMD, with an acceptable safety and efficacy profile.
authors: Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors: M
authors: M
authors: Jabbarvand
authors: Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors: H
authors: H
authors: Hashemian
authors: Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors: M
authors: M
authors: Khodaparast
authors: Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors: F
authors: F
authors: Bazvand
authors: Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors: A
authors: A
authors: Beheshtnejad
mesh_terms: D057128:Aberrometry; D000328:Adult; D003317:Corneal Dystrophies, Hereditary / Q000503:physiopathology / Q000601:surgery*; D063171:Corneal Pachymetry; D003319:Corneal Stroma / Q000601:surgery*; D019781:Corneal Topography; D057108:Corneal Wavefront Aberration / Q000503:physiopathology; D005260:Female; D006801:Humans; D053685:Laser Therapy / Q000379:methods*; D053844:Lasers, Solid-State / Q000627:therapeutic use; D008297:Male; D049451:Nomograms; D013508:Ophthalmologic Surgical Procedures; D011446:Prospective Studies; D019736:Prostheses and Implants; D019919:Prosthesis Implantation / Q000379:methods*; D012029:Refraction, Ocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult