Scanning laser polarimetry with variable and enhanced corneal compensation in normal and glaucomatous eyes.
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.
Sehi
Mitra
M
Department of Ophthalmology, University of Miami Miller School of Medicine, Bascom Palmer Eye Institute, Palm Beach Gardens, Florida 33418, USA.
Guaqueta
Delia C
DC
Feuer
William J
WJ
Greenfield
David S
DS
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