title: Scanning laser polarimetry with variable and enhanced corneal compensation in normal and glaucomatous eyes.
abstract: OBJECTIVE
  To investigate whether correction for atypical birefringence pattern (ABP) using scanning laser polarimetry with enhanced corneal compensation (SLP-ECC) reduces the severity of ABP compared with variable corneal compensation (SLP-VCC) and improves the correlation with visual function.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  Normal and glaucomatous eyes enrolled from four clinical sites underwent complete examination, automated perimetry, SLP-ECC, and SLP-VCC. Eyes were characterized in three groups based upon the typical scan score (TSS): normal birefringence pattern (NBP) was defined as TSS > or = 80, mild ABP as TSS 61 to 79, and moderate-severe ABP as TSS < or = 60. For each of four SLP parameters, the area under the ROC curve (AUROC) was calculated to compare the ability of SLP-ECC and SLP-VCC to discriminate between normal and glaucomatous eyes.
  
  
  RESULTS
  Eighty-four normal volunteers and 45 glaucoma patients were enrolled. Mean TSS was significantly (P < .001) greater using SLP-ECC (98.0 +/- 6.6) compared with SLP-VCC (83.4 +/- 22.5). The frequency of moderate-severe ABP images was significantly (P < .001, McNemar test) higher using SLP-VCC (18 of 129, 14%) compared with SLP-ECC (one of 129, 0.8%). Two SLP-ECC parameters (temporal superior nasal inferior temporal [TSNIT] average and inferior average) had significantly (P = .01, P < .001) higher correlation (r = .45, r = .50, respectively) with MD compared with SLP-VCC (r = .34, r = .37). Among eyes with moderate-severe ABP (n = 18), inferior average obtained using SLP-ECC had significantly (P = .03) greater AUROC (0.91 +/- 0.07) compared with SLP-VCC (0.78 +/- 0.11).
  
  
  CONCLUSIONS
  SLP-ECC significantly reduces the frequency and severity of ABP compared with SLP-VCC and improves the correlation between RNFL measures and visual function.
authors.affiliation: Department of Ophthalmology, University of Miami Miller School of Medicine, Bascom Palmer Eye Institute, Palm Beach Gardens, Florida 33418, USA.
authors.forename: Mitra
authors.initials: M
authors.lastname: Sehi
authors.forename: Delia C
authors.initials: DC
authors.lastname: Guaqueta
authors.forename: William J
authors.initials: WJ
authors.lastname: Feuer
authors.forename: David S
authors.initials: DS
authors.lastname: Greenfield
mesh_terms: D000328:Adult; D000368:Aged; D001718:Birefringence; D003315:Cornea / Q000502:physiology*; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D011446:Prospective Studies; D012372:ROC Curve; D012165:Retinal Ganglion Cells / Q000473:pathology; D014786:Vision Disorders / Q000175:diagnosis*; D014792:Visual Acuity; D058609:Visual Field Tests; D014794:Visual Fields