Using the Thickness Map from Macular Ganglion Cell Analysis to Differentiate Retinal Vein Occlusion from Glaucoma

Purpose: We hypothesized that the thickness map from macular ganglion cell analysis (GCA) acquired from spectral-domain optical coherence tomography can be used to differentiate retinal vein occlusion (RVO) from glaucoma. Methods: In this retrospective case control study, 37 patients with resolved RVO and 74 patients with primary open-angle glaucoma (POAG) were enrolled. Two independent examiners diagnosed patients with RVO or POAG based on the topographic pattern in the GCA thickness map. Inter-observer agreement for a decision between RVO and POAG was assessed using kappa statistics. Diagnostic specificity and accuracy were calculated. Results: Inter-observer agreement was good, with a kappa value of 0.765 (95% confidence interval, 0.634–0.896, p < 0.001). The diagnostic specificity of RVO from POAG using the GCA thickness map was 93.2% and diagnosis accuracy was 80.4%. Conclusions: An irregular GCA thickness map represents a simple and convenient differential diagnostic clue to distinguish RVO from POAG.