Anatomic Features of the Lamina Cribrosa and Optic Disc in Ocular Hypertension, Glaucoma and Healthy Eyes.

Abstract

Central lamina cribrosa thickness (LCT) was found to be higher in eyes with ocular hypertension (OHT) compared with primary open angle glaucoma (POAG) and healthy controls (HCs). To evaluate the anatomic features of lamina cribrosa (LC) and the optic disc (OD) using swept-source optical coherence tomography (OCT) in eyes with OHT. Treatment naive eyes with OHT and POAG and healthy eyes were included. All eyes underwent a complete ophthalmological examination in addition to swept-source OCT of the OD. Anatomic features of LC, including central LCT, LC depth, prelaminar depth (PLD), and prelaminar tissue thickness, were measured manually using the internal caliper function of the OCT device and compared within groups. OD ovality, disc-foveal angle, and OD torsion were measured on colored photographs, using imageJ software. Seventy-one eyes of 37 patients in the OHT group, 41 eyes of 26 patients in the POAG group, and 30 eyes of 30 patients in the HC group were enrolled in the study. Groups were similar in age and sex distribution. Central LCT was significantly higher in the OHT group, compared with HCs (333.8 ± 50.5 vs 304.5 ± 46.3 µm, P = 0.02) and POAG group (286.7 ± 140.4, P = 0.001). PLD and LC depth were both highest in POAG (282.3 ± 145.5 µm and 471.3 ± 195.2 µm), followed by OHT (244.8 ± 30.2 µm and 440.7 ± 18.7 µm) and HCs (170.1 ± 152.6 µm and 412.8 ± 80 µm), only the difference between POAG and HCs in PLD was statistically significant ( P = 0.03). Prelaminar tissue thickness, OD torsion, disc-foveal angle, and disc ovality showed no significant difference. LC was significantly thicker in eyes with OHT, compared with POAG and HCs. This finding may be relevant to optic nerve protection from high intraocular pressure in patients with OHT.