title: Retinal nerve fiber layer thickness measurements: uveitis, a major confounding factor.
abstract: OBJECTIVE
  To evaluate optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) measurements in patients with active and quiescent uveitis with and without glaucoma and compare results to the published age-adjusted normative data.
  
  
  METHODS
  Comparative, retrospective pilot study.
  
  
  METHODS
  Consecutive patients with uveitis who underwent OCT RNFL measurements between December 2011 and October 2012 were identified: 76 uveitic eyes without glaucoma and 135 uveitic eyes with glaucoma.
  
  
  METHODS
  We conducted OCT of the RNFL.
  
  
  METHODS
  Global and sectoral RNFL thickness measurements.
  
  
  RESULTS
  In 19 nonglaucomatous, uveitic eyes with active inflammation, mean global and all sectoral RNFL measurements were greater than the normative 95th percentile. The mean global RNFL OCT measurement was 140.5 microns in such eyes compared with 107.8 microns in the 57 nonglaucomatous, quiescent, uveitic eyes (P=0.008). These measurements were significantly higher than the average of 95.3 microns reported in normal eyes (P<0.001). All mean sectoral measurements except superonasal were significantly higher in active compared with quiescent uveitic eyes (P=0.002-0.05). In glaucomatous eyes with both quiescent and active uveitis, the mean global RNFL measurements on OCT were 92.3 and 95.7 microns, respectively. These measurements were significantly higher than the mean global RNFL thickness (65.3 microns) reported in eyes with the same stage (moderate) of nonuveitic glaucoma.
  
  
  CONCLUSIONS
  Uveitis is a major confounding factor in assessing the thickness of the RNFL. A significant thickening of the RNFL was found in patients with active uveitis and a greater RNFL thickness than anticipated in patients with uveitic glaucoma. These data raise concerns about the comparative value of RNFL scans as a method to detect and monitor glaucoma in uveitic eyes.
authors.affiliation: Duke University Eye Center, Durham, North Carolina.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Moore
authors.affiliation: Duke University Eye Center, Durham, North Carolina.
authors.forename: Glenn J
authors.initials: GJ
authors.lastname: Jaffe
authors.affiliation: Duke University Eye Center, Durham, North Carolina. Electronic address: asran002@mc.duke.edu.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Asrani
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D015986:Confounding Factors, Epidemiologic; D003430:Cross-Sectional Studies; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis / Q000453:epidemiology*; D010865:Pilot Projects; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D014605:Uveitis / Q000175:diagnosis / Q000453:epidemiology*; D014794:Visual Fields