title: Improved repeatability of retinal thickness measurements using line-scan ophthalmoscope image-based retinal tracking.
abstract: OBJECTIVE
  To assess repeatability and speed of a line-scan ophthalmoscope (LSO) image-based tracking system and compare to the point-scanning approach.
  
  
  METHODS
  Thirty-five eyes with retinal diseases underwent volume scans using two spectral-domain optical coherence tomography (OCT) devices: a line-scan tracking Cirrus HD-OCT (Carl Zeiss Meditec; Dublin, CA) and point-scan tracking Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany). Eyes were also imaged on the Cirrus HD-OCT with tracking disabled.
  
  
  RESULTS
  Mean difference in central subfield thickness (CST) between consecutive scans was 2.6 µm for the Cirrus without tracking, 1.7 µm with tracking, and 3.6 µm for the Spectralis. The repeatability standard deviation was 3.0 µm for the Cirrus without tracking, 1.5 µm with tracking, and 4.0 µm for the Spectralis. Coefficient of variation for the CST was 1.1% for the Cirrus without tracking, 0.5% with tracking, and 1.4% for the Spectralis. Mean scan acquisition time was 12.3 ± 6.2 seconds for the Spectralis, 7.8 ± 6.7 for the Cirrus with tracking, and 4.3 ± 0.6 for the Cirrus without tracking.
  
  
  CONCLUSIONS
  Real-time LSO image-based retinal tracking appears to improve repeatability of OCT retinal thickness measurements.
authors: Jennifer
authors: J
authors: Hu
authors: Cornelia B
authors: CB
authors: Gottlieb
authors: Daniel J
authors: DJ
authors: Barajas
authors: Cullen J
authors: CJ
authors: Barnett
authors: Tamera
authors: T
authors: Schoenholz
authors: SriniVas R
authors: SR
authors: Sadda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019721:Ophthalmoscopes; D009929:Organ Size; D011446:Prospective Studies; D015203:Reproducibility of Results; D012160:Retina / Q000473:pathology*; D012164:Retinal Diseases / Q000175:diagnosis*; D041623:Tomography, Optical Coherence / Q000295:instrumentation*; D014792:Visual Acuity