title: Foveal Photoreceptor Deformation as a Significant Predictor of Postoperative Visual Outcome in Idiopathic Epiretinal Membrane Surgery.
abstract: OBJECTIVE
  The purpose of this study was to determine whether the outer nuclear layer (ONL) deformation detected by spectral-domain optical coherence tomography (SD-OCT) is correlated with visual acuity before and after surgery in patients with idiopathic epiretinal membrane (ERM).
  
  
  METHODS
  Forty-four eyes of 44 patients who underwent vitreous surgery for treatment of ERM were included. All patients underwent comprehensive ophthalmologic evaluations including measurement of best corrected visual acuity (BCVA) and SD-OCT before and after surgery. The central foveal thickness (CFT), foveal ONL thickness, juxtafoveal ONL plus outer plexiform layer (OPL) thickness, photoreceptor outer segment thickness, and size of the disrupted interdigitation zone (IZ) line were measured. We defined the "photoreceptor deformation index" (PDI) as the ratio of foveal ONL thickness to the juxtafoveal ONL plus OPL thickness.
  
  
  RESULTS
  Multiple regression analysis showed that the only significant predictor of preoperative mean logarithm of the minimum angle of resolution (logMAR) BCVA was preoperative CFT (P < 0.0001). Preoperative PDI (P < 0.0001) and disrupted IZ diameter (P = 0.0242) were positively correlated with logMAR at 3 months after surgery. PDI (P < 0.0001) and disrupted IZ diameter (P = 0.0351) were also positively correlated with logMAR BCVA at 6 months after surgery. The only significant predictor of logMAR at 12 months after surgery was preoperative PDI (P < 0.0001).
  
  
  CONCLUSIONS
  Preoperative PDI was most significantly correlated with postoperative BCVA. These results suggest that PDI is a novel parameter predicting visual outcome after surgery in eyes with ERM.
authors.affiliation: Department of Ophthalmology and Visual Sciences Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan.
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Hosoda
authors.affiliation: Department of Ophthalmology and Visual Sciences Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan.
authors.forename: Sotaro
authors.initials: S
authors.lastname: Ooto
authors.affiliation: Department of Ophthalmology and Visual Sciences Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan 2Department of Ophthalmology, Saitama Medical School, Moroyama, Iruma, Saitama, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Hangai
authors.affiliation: Department of Ophthalmology and Visual Sciences Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Oishi
authors.affiliation: Department of Ophthalmology and Visual Sciences Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan.
authors.forename: Nagahisa
authors.initials: N
authors.lastname: Yoshimura
mesh_terms: D000368:Aged; D019773:Epiretinal Membrane / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D005584:Fovea Centralis / Q000473:pathology*; D006801:Humans; D008297:Male; D011184:Postoperative Period; D055211:Retinal Photoreceptor Cell Inner Segment / Q000473:pathology*; D055214:Retinal Photoreceptor Cell Outer Segment / Q000473:pathology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology*; D014821:Vitrectomy