title: Retinal measurements using time domain OCT imaging before and after myopic Lasik.
abstract: OBJECTIVE
  To compare retinal measurements obtained by time domain optical coherence tomography (OCT) devices before and after myopic laser in situ keratomileusis (Lasik) and to assess the interaction of Lasik and retinal structures as measured by time domain OCT.
  
  
  METHODS
  Fifty-three patients randomly selected participated in the study. Only the right eye of each subject was included in the study. Comprehensive ophthalmic examinations including refraction examination, slit lamp examination, dilated fundus examination, corneal topography, corneal thickness, intraocular pressure, and retinal Stratus OCT scans were acquired for each patient before myopic Lasik and 3months after surgery.
  
  
  RESULTS
  Total macular volume (TMV) changed significantly between preoperative and postoperative measurements (p=0.003). No statistical differences were found between preoperative and postoperative disc area, rim area, cup/disk vert. ratio, or average foveal thickness (p>0.05). The variation in TMV correlated significantly with the change in spherical refraction equivalent, maximal corneal curvature, minimal corneal curvature, and corneal ablation depth.
  
  
  CONCLUSIONS
  Most retinal OCT measurements undergo no obvious changes after myopic Lasik. The increased TMV measurements we measured after Lasik seem to be correlated with the alteration in corneal shape. The exact mechanism for this change is not clear, while we examined several possibilities including subclinical macular oedema, magnification changes, errors in OCT analysis and IOP, none of these seem to be a likely cause.
authors.affiliation: Eye Center, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Feng
authors.forename: Feng
authors.initials: F
authors.lastname: Lei
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Burns
authors.forename: Liqin
authors.initials: L
authors.lastname: Shao
authors.forename: Yabo
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D001699:Biometry; D003315:Cornea / Q000473:pathology; D019781:Corneal Topography / Q000379:methods; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D008266:Macula Lutea / Q000473:pathology; D008297:Male; D009216:Myopia / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D011184:Postoperative Period; D057234:Preoperative Period; D012029:Refraction, Ocular; D012160:Retina / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000379:methods; D055815:Young Adult