title: Refractive outcome of wavefront guided laser in situ keratomileusis and wavefront guided photorefractive keratectomy in high pre-existing higher order aberration.
abstract: OBJECTIVE
  To compare visual outcome and higher order aberrations (HOA) between wavefront-guided LASIK (WF-LASIK) and wavefront guided PRK (WF-PRK) in patients with high preoperative HOA.
  
  
  METHODS
  Randomized prospective interventional study. Conducted at Guru Nanak Eye Centre, Maulana Azad Medical College, Delhi, India. Eighty myopic eyes of forty patients were included.
  
  
  METHODS
  age more than 21 years, best corrected visual acuity of 20/20 or better, a stable refraction, to be off soft contact lens for minimum 14 days prior to preoperative examination, preoperative RMS HOA more than 0.35 μ, preoperative central corneal thickness at least 500 μm, estimated residual stromal bed thickness of at least 275 μm in patients undergoing WF-LASIK and 350 μm in patients undergoing WF-PRK. Exclusion criteria were severe dry eye, blepharitis, corneal disease and warpage, uveitis, posterior segment abnormalities involving the macula or optic nerve and systemic diseases. Patients were randomly divided into two groups. They underwent either WF-LASIK (group A) or WF-PRK (group B) over 2 years (40 eyes each). Patients were followed up for 6 months. Main outcome measures were efficacy, safety, stability, predictability and HOA.
  
  
  RESULTS
  At 6 months mean uncorrected visual acuity (logMAR) in group A was -0.01 ± 0.04 and group B was 0.00 ± 0.07 (P = 0.23). HOA RMS (6mm pupil) in group A was 0.61 ± 0.24 μm and group B was 0.55 ± 0.25 μm. The increase was statistically significant in both the groups (P < 0.05). Both the groups showed similar efficacy, predictability and safety.
  
  
  CONCLUSIONS
  WF-LASIK and WF-PRK have similar efficacy, safety and predictability, though WF-PRK induces less HOA.
authors.affiliation: Guru Nanak Eye Centre, Maharaja Ranjit Singh Marg, New Delhi 110002, India.
authors.forename: Ritu
authors.initials: R
authors.lastname: Arora
authors.affiliation: Guru Nanak Eye Centre, Maharaja Ranjit Singh Marg, New Delhi 110002, India. Electronic address: yashdoc17@gmail.com.
authors.forename: Yashpal
authors.initials: Y
authors.lastname: Goel
authors.affiliation: Guru Nanak Eye Centre, Maharaja Ranjit Singh Marg, New Delhi 110002, India.
authors.forename: Jawahar Lal
authors.initials: JL
authors.lastname: Goyal
authors.affiliation: Guru Nanak Eye Centre, Maharaja Ranjit Singh Marg, New Delhi 110002, India.
authors.forename: Gaurav
authors.initials: G
authors.lastname: Goyal
authors.affiliation: Guru Nanak Eye Centre, Maharaja Ranjit Singh Marg, New Delhi 110002, India.
authors.forename: Arushi
authors.initials: A
authors.lastname: Garg
authors.affiliation: Guru Nanak Eye Centre, Maharaja Ranjit Singh Marg, New Delhi 110002, India.
authors.forename: Parul
authors.initials: P
authors.lastname: Jain
mesh_terms: D057128:Aberrometry / Q000379:methods; D000328:Adult; D057108:Corneal Wavefront Aberration / Q000150:complications / Q000175:diagnosis* / Q000601:surgery*; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D008297:Male; D018903:Photorefractive Keratectomy / Q000379:methods*; D012029:Refraction, Ocular; D025321:Surgery, Computer-Assisted / Q000379:methods; D016896:Treatment Outcome; D014786:Vision Disorders / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D014792:Visual Acuity; D055815:Young Adult
keywords: Higher order aberrations; Lasik; Prk