title: The significance of cone outer segment tips as a prognostic factor in epiretinal membrane surgery.
abstract: OBJECTIVE
  To evaluate the prognostic value of the cone outer segment tips (COST) and other features using spectral-domain optical coherence tomography (SD-OCT) in patients undergoing epiretinal membrane (ERM) surgery.
  
  
  METHODS
  Retrospective observational case series.
  
  
  METHODS
  Fifty eyes of 49 patients that underwent vitrectomy for idiopathic ERM were studied. Best-corrected visual acuity (BCVA) and SD-OCT images were examined preoperatively and at 1 and 6 months postoperatively. The SD-OCT features evaluated included central foveal thickness (CFT) and the status and defect diameter of the external limiting membrane (ELM), the photoreceptor inner/outer segment (IS/OS) junction, and the COST line. The associations between SD-OCT parameters and BCVA were analyzed.
  
  
  RESULTS
  There was no ELM disruption found, and thus the eyes were categorized into 3 groups: Group A, with a continuous IS/OS and COST line; Group B, with a continuous IS/OS but disrupted COST line; and Group C, with a disrupted IS/OS and COST line. At 6 months, Group A showed a significantly better BCVA than Group B (P<.005), and poorer BCVA was noted in Group C (P=.034). Defect diameters of IS/OS and COST line were also significantly correlated with BCVA postoperatively. The BCVA at 6 months was better in order of Group A, B, and C as assigned at baseline (P<.05) or 1 month (P<.001). There was no significant correlation between CFT and BCVA.
  
  
  CONCLUSIONS
  The status of the COST line, in conjunction with the IS/OS junction, is a useful prognostic factor after ERM surgery.
authors.affiliation: Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Shimozono
authors.forename: Akio
authors.initials: A
authors.lastname: Oishi
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hata
authors.forename: Takaaki
authors.initials: T
authors.lastname: Matsuki
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Ito
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ishida
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kurimoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002387:Cataract Extraction; D019773:Epiretinal Membrane / Q000175:diagnosis* / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; 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; D014821:Vitrectomy