title: Outer retinal morphological changes and visual function after removal of epiretinal membrane.
abstract: OBJECTIVE
  To determine the relation between the recovery of the cone outer segment tips (COST) line and the best-corrected visual acuity (BCVA) after epiretinal membrane (ERM) surgery.
  
  
  METHODS
  Retrospective, consecutive, interventional case series.
  
  
  METHODS
  Sixty-one eyes of 56 patients with an idiopathic ERM were studied. All participants underwent a complete ophthalmic examination including spectral-domain optical coherence tomography before and after ERM removal surgery.
  
  
  METHODS
  The integrities of the photoreceptor layer including the external limiting membrane line, photoreceptor inner segment/outer segment (IS/OS) line, and COST line in the spectral-domain optical coherence tomography images at the fovea were determined. The associations of these morphological parameters to the BCVA were determined.
  
  
  RESULTS
  Better BCVAs were found more frequently in eyes with an intact COST line than in eyes with a disrupted or absent COST line at 1 (p < 0.001), 6 (p = 0.003), and 12 months (p < 0.001). Among the external limiting membrane, IS/OS, and COST line parameters, the IS/OS line had higher correlations with the BCVA by multivariate analysis. No significant difference was observed in central retinal thickness between eyes with intact and nonintact COST lines. Eight (30.8%) of 26 eyes with BCVA ≥ 20/20 had nonintact COST lines at 12 months after the ERM surgery.
  
  
  CONCLUSIONS
  Eyes with an intact COST line had better BCVA after ERM surgery. However, even at 12 months after ERM surgery, COST lines remained disrupted in many eyes with good BCVA.
authors.affiliation: Kyorin Eye Center, Kyorin University School of Medicine, Tokyo, Japan; Department of Ophthalmology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
authors.forename: Tosho
authors.initials: T
authors.lastname: Rii
authors.affiliation: Kyorin Eye Center, Kyorin University School of Medicine, Tokyo, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Itoh
authors.affiliation: Kyorin Eye Center, Kyorin University School of Medicine, Tokyo, Japan. Electronic address: inoue@eye-center.org.
authors.forename: Makoto
authors.initials: M
authors.lastname: Inoue
authors.affiliation: Kyorin Eye Center, Kyorin University School of Medicine, Tokyo, Japan.
authors.forename: Kazunari
authors.initials: K
authors.lastname: Hirota
authors.affiliation: Kyorin Eye Center, Kyorin University School of Medicine, Tokyo, Japan.
authors.forename: Akito
authors.initials: A
authors.lastname: Hirakata
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019773:Epiretinal Membrane / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020127:Recovery of Function; D017949:Retinal Cone Photoreceptor Cells / Q000473:pathology*; D055214:Retinal Photoreceptor Cell Outer Segment / Q000473:pathology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology*