title: Optical coherence tomography errors in glaucoma.
abstract: OBJECTIVE
  To demonstrate the types and prevalence of errors associated with the use of optical coherence tomography in a cross section of glaucoma patients. The association of different types of artifacts and certain coexisting ocular diagnoses was also evaluated.
  
  
  METHODS
  The optical coherence tomography data of glaucoma patients in a 3-month period was evaluated for evidence of errors in peripapillary retinal nerve fiber layer (RNFL) map and the macular thickness map. Signal strengths, centering errors, individual scan errors, and association with ocular conditions were noted. Logistic regression was used to assess the significance of continuous and categorical variables in predicting the presence of artifacts.
  
  
  RESULTS
  Macular scan artifacts were present in 16.8% and RNFL scan artifacts in 15.7% of 89 eyes of 89 patients studied. RNFL off-center scan was the most common error (34.8%). For macular thickness, 100% of the scans were artifact free for signal strength 8 or higher. However, for signal strength of < or =4, 64.3% had artifacts. For RNFL thickness, a signal strength > or =6, 96% of the scans had no artifacts. However, for signal strength < or =4, 86% had artifacts. Macular scan artifacts were present more commonly in patients with dry eye and RNFL centering errors were more frequent in eyes with cataracts.
  
  
  CONCLUSIONS
  A majority of glaucoma patients have artifact free scans. The final printouts of macular and RNFL thickness can identify most errors except for individual macular scan errors.
authors: Department of Ophthalmology, Duke University Eye Center, Durham, NC 27710, USA. sanjay.asrani@duke.edu
authors: Sanjay
authors: S
authors: Asrani
authors: Benjeil
authors: B
authors: Edghill
authors: Yogesh
authors: Y
authors: Gupta
authors: Guillermo
authors: G
authors: Meerhoff
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D002386:Cataract / Q000150:complications; D003951:Diagnostic Errors; D015352:Dry Eye Syndromes / Q000150:complications; D005260:Female; D005901:Glaucoma / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D008266:Macula Lutea / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology; D012160:Retina / Q000473:pathology; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence / Q000592:standards*; D055815:Young Adult