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Updated: Aug 19, 2026
Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
Published on: September 16, 2025
Quantitative assessment of atypical birefringence images using scanning laser polarimetry with variable corneal
Harmohina Bagga1, David S Greenfield, William J Feuer
1Department of Ophthalmology, University of Miami School of Medicine, Bascom Palmer Eye Institute, Miami, Florida, USA.
Purpose:
To define the clinical characteristics of atypical birefringence images and to describe a quantitative method for their identification.
Design:
Prospective, comparative, clinical observational study.
Methods:
Normal and glaucomatous eyes underwent complete examination, standard automated perimetry, scanning laser polarimetry with variable corneal compensation (GDx-VCC), and optical coherence tomography (OCT) of the macula, peripapillary retinal nerve fiber layer (RNFL), and optic disk. Eyes were classified into two groups: normal birefringence pattern (NBP) and atypical birefringence pattern (ABP). Clinical, functional, and structural characteristics were assessed separately. A multiple logistic regression model was used to predict eyes with ABP on the basis of a quantitative scan score generated by a support vector machine (SVM) with GDx-VCC.
Results:
Sixty-five eyes of 65 patients were enrolled. ABP images were observed in 5 of 20 (25%) normal eyes and 23 of 45 (51%) glaucomatous eyes. Compared with eyes with NBP, glaucomatous eyes with ABP demonstrated significantly lower SVM scores (P < .0001, < 0.0001, 0.008, 0.03, and 0.03, respectively) and greater temporal, mean, inferior, and nasal RNFL thickness using GDx-VCC; and a weaker correlation with OCT generated RNFL thickness (R(2) = .75 vs .27). ABP images were significantly correlated with older age (R(2) = .16, P = .001). The SVM score was the only significant (P < .0001) predictor of ABP images and provided high discriminating power between eyes with NBP and ABP (area under the receiver operator characteristic curve = 0.98).
Conclusions:
ABP images exist in a subset of normal and glaucomatous eyes, are associated with older patient age, and produce an artifactual increase in RNFL thickness using GDx-VCC. The SVM score is highly predictive of ABP images.
