Reversal of Lamina Cribrosa Displacement after Intraocular Pressure Reduction in Open-Angle Glaucoma

Abstract

To compare the change in lamina cribrosa (LC) displacement in response to intraocular pressure (IOP) lowering in patients with open-angle glaucoma (OAG) using spectral-domain optical coherence tomography (SD-OCT). Observational case series. One hundred eyes of 100 patients with OAG in whom IOP at the follow-up examination had decreased by at least 20% compared with the baseline IOP. Serial horizontal B-scan images of the optic nerve head (ONH) were obtained from each eye using enhanced depth imaging SD-OCT. Approximately 65 B-scans covering the optic discs were obtained before and 3 to 6 months after lowering IOP. The baseline and follow-up LC depths (the distance from the Bruch's membrane opening plane to the level of the anterior LC surface) were measured in B-scan images from each eye. The mean and maximum amount of reductions in LC depth measured in the 7 selected B-scan images. Intraocular pressure decreased from 21.2±9.1 to 10.5±2.6 mmHg. The percent of IOP reduction was significantly related to the untreated IOP (P < 0.001). There was a significant decrease in the LC depth at the follow-up examination compared with the baseline value (P < 0.001). The magnitude of LC depth reduction was significantly associated with younger age, higher untreated IOP, higher baseline IOP, and greater percent of IOP reduction (all P < 0.02). Reversal of the LC displacement was observed after IOP-lowering treatment in OAG. The degree of LC displacement reversal was related to the amount of IOP lowering.