title: Diagnostic value of GDx polarimetry in a Taiwan Chinese population.
abstract: OBJECTIVE
  To study the diagnostic ability of scanning laser polarimetry with variable corneal compensation (GDx VCC) for early glaucomatous (EG) eyes and glaucoma-suspect (GS) eyes in a Taiwan Chinese population.
  
  
  METHODS
  This prospective cross-sectional study included 82 EG eyes (mean deviation, MD: -3.32 +/- 2.20 dB), 45 GS eyes (MD: -2.43 +/- 2.16 dB), and 62 normal eyes. Retinal nerve fiber layer thickness of each subject was measured using GDx VCC and Humphrey Field Analyzer visual field testing. Measured GDx VCC parameters were compared among groups. The area under the receiver operating characteristic (AROC) curve of each parameter was used to differentiate normal from EG eyes or GS eyes. The correlation between MD and each parameter was also evaluated.
  
  
  RESULTS
  For both normal versus EG and normal versus GS, the largest AROC values were for nerve fiber indicator, superior average thickness, and inferior average thickness. There was no significant correlation between MD and GDx-VCC-measured parameters either in EG or GS eyes.
  
  
  CONCLUSIONS
  GDx VCC shows only moderate ability to distinguish normal eyes from eyes with early glaucoma. However, its diagnostic role in eyes with suspicious discs and normal visual fields is uncertain at this moment in the Taiwan Chinese population. Further studies are needed to address this issue.
authors.affiliation: Department of Ophthalmology, China Medical University Hospital, Taiching City, Taiwan. hsin7850@url.com.tw
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Chen
authors.forename: Mei-Ling
authors.initials: ML
authors.lastname: Huang
authors.forename: Yi-Yu
authors.initials: YY
authors.lastname: Tsai
authors.forename: Por-Tying
authors.initials: PT
authors.lastname: Hung
mesh_terms: D000328:Adult; D044466:Asian People; D003430:Cross-Sectional Studies; D004867:Equipment Design; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000208:ethnology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D012165:Retinal Ganglion Cells / Q000473:pathology*; D013624:Taiwan / Q000453:epidemiology; D013997:Time Factors; D058609:Visual Field Tests; D014794:Visual Fields