Indian Journal of Ophthalmology (Jan 2016)
Lamina depth and thickness correlate with glaucoma severity
Abstract
Purpose: To evaluate the correlation between lamina cribrosa (LC) morphology and glaucoma severity in patients with primary forms of open-angle glaucoma (OAG) using enhanced depth imaging spectral-domain optical coherence tomography (SD-OCT) and Humphrey visual field test (HVF). Subjects and Methods: Patients with OAG (n = 166), divided into normal-tension glaucoma (NTG) and high-tension glaucoma (HTG) groups (n = 66 and n = 100), were imaged using SD-OCT to obtain horizontal B-scan images of the optic nerve head (ONH). Laminar depth (LD) and laminar thickness (LT) were measured at the center of ONH. Results: The mean (±standard deviation) values of LD, LT, and visual field mean deviation (MD) were 555.4 ± 142.3 μm, 179.9 ± 49.7 μm, and − 5.7 ± 6.4 dB, respectively. In the multivariate linear regression analysis, LD, LT, and intraocular pressure (IOP) were significantly correlated with MD (P = 0.007, P = 0.037, and P = 0.004, respectively). In the subgroup analyses, only LD was associated with MD in the NTG group (n = 66), whereas LT and IOP were correlated with MD in the HTG group (n = 100). Neither axial length nor central corneal thickness was associated with LD or LT. Conclusions: Glaucoma severity, as measured by HVF MD, shows significant correlations with LD and LT, with greater severity associated with increasing LD and decreasing LT. Normal- and high-tension OAG patients have different associations with LD and LT, which implies that the pathogenesis of these two entities might be different.
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