PURPOSE. To investigate whether the lamina cribrosa (LC) curvature is decreased after trabeculectomy. METHODS. Thirty-nine eyes of 39 patients with primary open-angle glaucoma who underwent trabeculectomy were included. Optic nerves were scanned by using enhanced-depth-imaging spectral-domain optical coherence tomography before and after trabeculectomy. The LC curvature was assessed by measuring the LC curvature index (LCCI) in seven horizontal Bscan images in each eye. RESULTS. The LCCI was significantly smaller at postoperative 6 months than at the preoperative level in all seven planes (all P < 0.001). Preoperative LCCI was associated with younger age at superior midperiphery, midhorizontal plane, inferior midperiphery (all P 0.005) and higher preoperative intraocular pressure (IOP) at superior and inferior midperiphery (both P ¼ 0.039). Younger age and larger preoperative LCCI were associated with a larger reduction of the LCCI at all three locations (P ¼ 0.003 and 0.031 at superior midperiphery, P ¼ 0.011 and 0.001 at midhorizontal plane, and P ¼ 0.014 and 0.005 at inferior midperiphery, respectively), whereas the percentage IOP lowering was associated at superior and inferior midperiphery (P ¼ 0.017 and 0.047, respectively). CONCLUSIONS. Lamina cribrosa curvature was reduced after trabeculectomy. This finding suggests that LC curvature may have value as a parameter relevant to optic nerve head biomechanics
