canning laer polarimetry with variable corneal compenation and optical coherence tomography in normal and glaucomatou eye

Purpoe To evaluate the relationhip between viual function and retinal nerve fiber layer (RNFL) meaurement obtained with canning laer polarimetry with variable corneal compenation (LP-VCC) and optical coherence tomography (OCT). Deign Cro-ectional analyi of normal and glaucomatou eye in a tertiary care academic referral practice. Method A commercial GDx nerve fiber analyzer wa modified to enable the meaurement of corneal polarization axi and magnitude o that compenation for corneal birefringence wa eye pecific. Complete examination, LP with fixed corneal compenation (FCC) and variable corneal compenation (VCC), optical coherence tomography (OCT) imaging of the peripapillary RNFL, and automated achromatic perimetry were performed in all ubject. Excluion criteria were viual acuity le than 20/40, dieae other than glaucoma, and unreliable perimetry. Reult Fifty-nine patient (59 eye; 29 normal, 30 glaucomatou) were enrolled (mean age, 56.7 ± 20.3 year, range, 20–91). All eye with glaucoma had aociated viual field lo (average mean defect, −8.4 ± 5.8 dB). Uing LP-FCC, nine of 12 retardation parameter (75%) were ignificantly le in glaucomatou eye. Uing LP-VCC, 11of 12 retardation parameter (92%) were ignificantly le in glaucomatou eye. Multiple regreion model contructed for each retardation parameter with viual field demontrated that the following VCC parameter were tatitically ignificant wherea FCC parameter were not: ellipe average (FCC, P = .28, VCC, P = .001), uperior average (FCC, P = .38, VCC, P < .001), inferior average (FCC, P = .10, VCC, P = .008), average thickne (FCC, P = .30, VCC, P = .031), and uperior integral (FCC, P = .43, VCC, P = .001). imilar reult were obtained for multiple regreion model contructed with OCT-derived RNFL thickne: ellipe average (FCC, P = .99, VCC, P = .002), uperior average (FCC, P = .90, VCC, P < .001), inferior average (FCC, P = .61, VCC, P = .007), and uperior integral (FCC, P = .92, VCC, P < .001). Concluion Compared with fixed compenation, mean-baed LP parameter generated with LP-VCC have greater correlation with viual function and RNFL thickne aement obtained with OCT