title: Evaluation of screening versus regular polarimetry.
abstract: OBJECTIVE
  The purpose of this study is to evaluate a new screening program for the GDx VCC (variable corneal compensation) retinal nerve fiber layer analyzer. This new method uses a fast screening approach to detect retinal nerve fiber layer loss associated with glaucoma. The study evaluates the sensitivity and specificity of the screening program and compares the results with those from the GDx VCC full examination.
  
  
  METHODS
  One hundred seventeen eyes from 60 subjects with a mean age of 60.65 years (range, 41-79 years old) were analyzed. Subjects were divided into a normal or glaucoma group based on an ophthalmic examination. Each individual underwent a GDx VCC screening examination, GDx full examination, Humphrey HFA II 24-2 SITA Standard visual field, intraocular pressure assessment, and dilated optic nerve examination. The outcome for the GDx screening examination was within normal limits, borderline, or outside normal limits and compared with the GDx full examination results.
  
  
  RESULTS
  The sensitivity and specificity for the GDx full examination were 73% and 79%, respectively. The sensitivity and specificity for the screening method were 67% and 91%, respectively. The full examination was more sensitive; however, the screening examination was more specific.
  
  
  CONCLUSIONS
  The screening examination is more conservative than the full examination algorithm and may miss some individuals with glaucomatous damage that the full examination may identify. However, the number of false-positives for the screening examination is less than the full examination method.
authors.affiliation: Department of Veterans Affairs, New York Harbor Health Care System, Brooklyn, New York, USA. murray.fingeret@med.va.gov
authors.forename: Murray
authors.initials: M
authors.lastname: Fingeret
authors.forename: Tanvi
authors.initials: T
authors.lastname: Patel
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015351:Vision Screening / Q000379:methods*