title: Intrasession repeatability of optical coherence tomography measures in active neovascular age-related macular degeneration.
abstract: OBJECTIVE
  To determine the repeatability of Stratus optical coherence tomography fast macular thickness map analysis in patients with active neovascular age-related macular degeneration (nAMD).
  
  
  METHODS
  Consecutive pairs of scans from 112 eyes of 112 consecutive patients with active nAMD were analyzed. The Bland-Altman coefficient of repeatability (CR) was calculated for each retinal thickness or volume measure.
  
  
  RESULTS
  The CR for the central 1 mm macular subfield was 59 μm (18% of retinal thickness) and did not exceed 69 μm in any subfield. There was much poorer repeatability for the center-point thickness (CPT) measure (CR of 78 μm; 24%). However, in the subgroup of 38 patients with no Stratus software low analysis confidence message on either analysis map, the revised CR (42 μm) for the CPT measure and the A1 subfield (40 μm) were similar.
  
  
  CONCLUSIONS
  Optical coherence tomography-derived retinal thickness measurements are subject to measurement variability in patients with active nAMD. The results suggest a change criterion of more than 59 μm in central 1 mm (A1) subfield macular thickness is necessary to distinguish true clinical change from measurement variability in these patients.
authors.affiliation: Moorfields Eye Hospital, London, UK. praveen.patel@moorfields.nhs.uk
authors.forename: Praveen J
authors.initials: PJ
authors.lastname: Patel
authors.forename: Fred K
authors.initials: FK
authors.lastname: Chen
authors.forename: Felicia
authors.initials: F
authors.lastname: Ikeji
authors.forename: Matthew
authors.initials: M
authors.lastname: Richardson
authors.forename: Lyndon Da
authors.initials: LD
authors.lastname: Cruz
authors.forename: Adnan
authors.initials: A
authors.lastname: Tufail
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012160:Retina / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000592:standards*; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors; D014792:Visual Acuity / Q000502:physiology; D057135:Wet Macular Degeneration / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology
chemical_list: D020533:Angiogenesis Inhibitors; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A