title: Comparing retinal thickness measurements from Cirrus spectral domain- and Stratus time domain-optical coherence tomography.
abstract: OBJECTIVE
  The purpose of this study was to compare retinal measurements obtained using spectral domain-optical coherence tomography with measurements obtained using time domain-optical coherence tomography.
  
  
  METHODS
  Three hundred and seventy subjects were recruited at three university-based and one community-based retina practice for a cross-sectional observational study. For each subject, one eye was enrolled as the study eye. A Stratus Fast Macular scan was performed, and a Cirrus 200 x 200 Macular Cube scan was performed. Both instruments segment the acquired images to generate retinal thickness values and report averages measured in nine subfields defined by the Early Treatment Diabetic Retinopathy Study. These average values were compared with each other quantitatively using linear regression and Bland-Altman plots.
  
  
  RESULTS
  Of the recruited subjects, 283 had acceptable images taken on the same day with both the Cirrus and Stratus devices. Mean differences between the instruments were noted in all subfields for all disease categories and ranged from 29 microm (outer superior subfield) to 54 microm (central subfield).
  
  
  CONCLUSIONS
  Differences between time domain and spectral domain measurements of retinal thickness depend on pathology and location. Comparisons across instruments should be made with caution.
authors.affiliation: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. wolfgang.geitzenauer@meduniwien.ac.at
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Geitzenauer
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Kiss
authors.forename: Mary K
authors.initials: MK
authors.lastname: Durbin
authors.forename: Maria Teresa A
authors.initials: MT
authors.lastname: Abunto
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Callan
authors.forename: Paul F
authors.initials: PF
authors.lastname: Stetson
authors.forename: Mark R
authors.initials: MR
authors.lastname: Wieland
authors.forename: Neil M
authors.initials: NM
authors.lastname: Bressler
authors.forename: Giovanni
authors.initials: G
authors.lastname: Gregori
authors.forename: Ursula M
authors.initials: UM
authors.lastname: Schmidt-Erfurth
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012160:Retina / Q000473:pathology*; D012164:Retinal Diseases / Q000145:classification / Q000473:pathology*; D012189:Retrospective Studies; D013997:Time Factors; D041623:Tomography, Optical Coherence / Q000379:methods*; D055815:Young Adult