Intereye Comparison of Lamina Cribrosa Curvature in Normal Tension Glaucoma Patients With Unilateral Damage.

Abstract

To investigate intereye differences in lamina cribrosa (LC) morphology in normal tension glaucoma (NTG) patients with unilateral damage. A total of 152 eyes of 76 treatment-naive NTG patients with unilateral damage from the ongoing Investigating Glaucoma Progression Study were included. Optic nerve heads were scanned using enhanced-depth spectral-domain optical coherence tomography. The magnitude of the LC curve and LC position were assessed by measuring the LC curve index (LCCI) and LC depth (LCD), respectively, at seven locations spaced equidistantly across the vertical optic disc diameter. LCCI and LCD were compared between glaucomatous and fellow healthy eyes. Eyes with NTG had larger average LCCI and LCD than contralateral healthy eyes (for both P < 0.002). The LCCI was greater in the glaucomatous eyes at all seven locations (P < 0.001). Univariate conditional logistic regression analysis showed that higher baseline intraocular pressure (P = 0.010), deeper LCD (P = 0.007), and larger LCCI (P < 0.001) were significantly associated with the presence of glaucoma. In multivariate analysis, only larger LCCI was significantly associated with the presence of glaucoma (P < 0.001). Glaucomatous eyes have more steeply curved LC than fellow healthy eyes. This finding suggests that LC undergoes significant remodeling in NTG eyes.