title: Comparison of Refractive Error Changes in Retinopathy of Prematurity Patients Treated with Diode and Red Lasers.
abstract: OBJECTIVE
  To compare refractive error changes in retinopathy of prematurity (ROP) patients treated with diode and red lasers.
  
  
  METHODS
  A randomized double-masked clinical trial was performed, and infants with threshold or prethreshold type 1 ROP were assigned to red or diode laser groups. Gestational age, birth weight, pretreatment cycloplegic refraction, time of treatment, disease stage, zone and disease severity were recorded. Patients received either red or diode laser treatment and were regularly followed up for retina assessment and refraction. The information at month 12 of corrected age was considered for comparison.
  
  
  RESULTS
  One hundred and fifty eyes of 75 infants were enrolled in the study. Seventy-four eyes received diode and 76 red laser therapy. The mean gestational age and birth weight of the infants were 28.6 ± 3.2 weeks and 1,441 ± 491 g, respectively. The mean baseline refractive error was +2.3 ± 1.7 dpt. Posttreatment refraction showed a significant myopic shift (mean 2.6 ± 2.0 dpt) with significant difference between the two groups (p < 0.001). There was a greater myopic shift among children with zone I and diode laser treatment (mean 6.00 dpt) and a lesser shift among children with zone II and red laser treatment (mean 1.12 dpt). The linear regression model, using the generalized estimating equation method, showed that the type of laser used has a significant effect on myopic shift even after adjustment for other variables.
  
  
  CONCLUSIONS
  Myopic shift in laser-treated ROP patients is related to the type of laser used and the involved zone. Red laser seems to cause less myopic shift than diode laser, and those with zone I involvement have a greater myopic shift than those with ROP in zone II.
authors.affiliation: Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ramak
authors.initials: R
authors.lastname: Roohipoor
authors.forename: Reza
authors.initials: R
authors.lastname: Karkhaneh
authors.forename: Mohammad
authors.initials: M
authors.lastname: Riazi Esfahani
authors.forename: Fateme
authors.initials: F
authors.lastname: Alipour
authors.forename: Mahtab
authors.initials: M
authors.lastname: Haghighat
authors.forename: Nazanin
authors.initials: N
authors.lastname: Ebrahimiadib
authors.forename: Mohammad
authors.initials: M
authors.lastname: Zarei
authors.forename: Ramin
authors.initials: R
authors.lastname: Mehrdad
mesh_terms: D001724:Birth Weight; D004311:Double-Blind Method; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D017075:Laser Coagulation / Q000009:adverse effects*; D054023:Lasers, Semiconductor / Q000009:adverse effects*; D053844:Lasers, Solid-State / Q000009:adverse effects*; D009216:Myopia / Q000209:etiology* / Q000503:physiopathology; D012178:Retinopathy of Prematurity / Q000503:physiopathology / Q000601:surgery*; D014792:Visual Acuity