Influence of Bruch's Membrane Opening Area in Diagnosing Glaucoma With Neuroretinal Parameters From Optical Coherence Tomography

Abstract

To determine whether the glaucoma diagnostic accuracy of age- and Bruch membrane opening area (BMOA)-adjusted normative classifications of minimum rim width (MRW) and retinal nerve fiber layer thickness (RNFLT) is dependent on BMOA, in a European descent population. Retrospective, cross-sectional study. We included 182 glaucoma patients and 166 healthy controls for the primary study, and 105 glaucoma patients in a second sample used for a replication study. Optical coherence tomography (Spectralis) measurements of BMOA, global MRW, and RNFLT and normative classifications from the device software were exported for analysis. Sensitivity and specificity were calculated for a conservative criterion (abnormal= "outside normal limits" classification) and a liberal criterion (abnormal= "outside normal limits" or "borderline" classifications). The dependence of sensitivity and specificity on BMOA was analyzed with comparison among subgroups divided by tertiles of BMOA, and with logistic regression. For the conservative criterion, MRW sensitivity was independent of BMOA (P ≥ .76), while RNFLT sensitivity increased in the large BMOA subgroup (P= .04, odds ratio: 1.2 per mm2 [P= .02]). For the liberal criterion, MRW and RNFLT sensitivities were independent of BMOA (P ≥ .53). Specificities were independent of BMOA (P ≥ .07). For the replication sample, which included younger patients with larger BMOA and worse visual field damage than the primary sample, sensitivities were independent of BMOA for both criteria (P ≥ .10). RNFLT sensitivity was higher in eyes with larger BMOA; however, age and visual field damage may influence that association. MRW diagnostic accuracy was not dependent on BMOA.