Glaucomatous Remodeling of the Lamina Cribrosa: Association With Visual Field Progression

Purpose: To determine whether rates of change in lamina cribrosa (LC) depth and curvature in POAG patients are associated with rates of visual field (VF) progression. Methods: We used 24 radial B-scan spectral domain optic coherence tomographic images to define anterior LC surface depth (ALCSD) and LC curvature index (LCCI), which were segmented by deep learning. Linear mixed effects models tested the associations between VF progression rate, ALCSD, LCCI, and demographic and clinical characteristics. Results: Progressive posterior remodeling of LC (i.e., increasing depth; -0.095 dB/year/10 microns; P < 0.001) and increasing LCCI (i.e., posterior bowing; -0.110 dB/year/unit; P < 0.001) each independently predicted faster rates of VF progression. The same degree of ALCSD change was associated with faster progression in eyes that were younger (P = 0.038), had higher central corneal thickness (CCT) (P < 0.001), or had higher mean IOP (P = 0.030). Similarly, the same amount of LCCI change was correlated with greater baseline age (P < 0.001) and lower CCT (P < 0.001). Thus, functionally progressive glaucoma was associated with less change in ALCSD and LCCI in older subjects and subjects with thicker CCT and lower mean IOP over the follow-up period. Conclusions: Glaucomatous remodeling of the LC is associated with VF progression in POAGs. The association between longitudinal structural remodeling and functional progression varies with age such that older individuals exhibit shallower remodeling (less posterior change in ALCSD and LCCI). Subjects with a higher IOP and thinner CCT showed greater posterior remodeling of the LC as glaucoma functionally progressed, indicating that these factors are mechanistically relevant to glaucomatous remodeling.