title: Relationship between Outer Retinal Layers Thickness and Visual Acuity in Diabetic Macular Edema.
abstract: OBJECTIVE
  To investigate the correlation of outer retinal layers (ORL) thickness and visual acuity (VA) in patients with diabetic macular edema (DME).
  
  
  METHODS
  Consecutive DME patients seen at the Retina Clinic of The University of Hong Kong were recruited for OCT assessment. The ORL thickness was defined as the distance between external limiting membrane (ELM) and retinal pigment epithelium (RPE) at the foveal center. The correlation between total retinal thickness, ORL thickness, and vision was calculated.
  
  
  RESULTS
  78 patients with DME were recruited. The mean age was 58.1 years (±11.5 years) and their mean visual acuity measured with Snellen chart was 0.51 (±0.18). The correlation coefficient between total retinal thickness and visual acuity was 0.34 (P < 0.001) whereas the correlation coefficient was 0.65 between ORL thickness and visual acuity (P < 0.001).
  
  
  CONCLUSIONS
  ORL thickness correlates better with vision than the total retinal thickness. It is a novel OCT parameter in the assessment of DME. Moreover, it could be a potential long term visual prognostic factor for patients with DME.
authors.affiliation: Department of Ophthalmology, The University of Hong Kong, Room 301, Level 3, Block B, Cyberport 4, Pokfulam, Hong Kong ; Department of Ophthalmology and Visual Science, The Chinese University of Hong Kong, Kowloon, Hong Kong.
authors.forename: Raymond L M
authors.initials: RL
authors.lastname: Wong
authors.affiliation: Department of Ophthalmology, The University of Hong Kong, Room 301, Level 3, Block B, Cyberport 4, Pokfulam, Hong Kong ; Department of Ophthalmology, Caritas Medical Centre, Kowloon, Hong Kong.
authors.forename: Jacky W Y
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Ophthalmology, Caritas Medical Centre, Kowloon, Hong Kong.
authors.forename: Gordon S K
authors.initials: GS
authors.lastname: Yau
authors.affiliation: Department of Ophthalmology, The University of Hong Kong, Room 301, Level 3, Block B, Cyberport 4, Pokfulam, Hong Kong.
authors.forename: Ian Y H
authors.initials: IY
authors.lastname: Wong
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003930:Diabetic Retinopathy / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008269:Macular Edema / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000473:pathology*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology*