Agreement between the newly developed OCT glaucoma staging system and the standardized visual field glaucoma staging system 2

Abstract

Purpose: The purpose of this research was to assess the agreement between the new optical coherence tomography (OCT) glaucoma staging system (GSS) and the visual field (VF) GSS 2 (GSS2). Methods: This is a cross-sectional study of 161 eyes of 110 patients with controlled primary open-angle glaucoma (POAG). All eyes were subjected to VF examination using standard automated perimetry and Humphrey field analyzer II 750. GSS2 was used for the classification of the VF defects’ severity. OCT of the optic disc and the macular ganglion cell complex (GCC) was performed using RTVue. Patients were classified by OCT GSS into six stages. Results: The study examined 161 eyes of 110 patients with controlled POAG. The staging according to VF GSS2 was as follows: stage 0 (12.42%), border stage (12.42%), stage 1 (13.04%), stage 2 (14.29%), stage 3 (14.28%), stage 4 (14.28%), and stage 5 (19.25%). The staging by OCT GSS was as follows: stage 0 (18.6 %), border stage (17.3%), stage 1 (6.8%), stage 2 (9.31%), stage 3 (6%), stage 4 (11.8%), and stage 5 (30.43%). The sensitivity of the new OCT GSS was different in different stages of glaucoma. In this study, no normal control group was considered; thus, the specificity could not be calculated. There was moderate agreement between the two staging systems. Conclusions: OCT GSS is a reliable and objective method for diagnosing and monitoring glaucoma. Correlations were found between GSS2, inferior and total macular GCC thickness values, and cup-to-disc ratios, so considering these items as additional parameters may make this new classification even more sensitive than VF GSS2.