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

Prcis: Central lamina cribrosa thickness was found to be higher in eyes with ocular hypertension, compared to primary open angle glaucoma and healthy controls.

Purpose: To evaluate the anatomical features of lamina cribrosa (LC) and the optic disc (OD) using swept-source optical coherence tomography (OCT) in eyes with ocular hypertension (OHT).

Materials and methods: Treatment naive eyes with OHT and primary open angle glaucoma (POAG) and healthy eyes were included. All eyes underwent a complete ophthalmological examination in addition to swept-source OCT of optic disc. Anatomical features of LC, including central LC thickness(LCT), LC depth (LCD), prelaminar depth (PLD), pre-laminar tissue thickness (PLTT) were measured manually using the internal caliper function of the OCT device and compared within groups. Optic disc ovality, disc-foveal angle and optic disc torsion were measured on colored photographs, using imageJ software.

Results: Seventy one eyes of 37 patients in OHT group, 41 eyes of 26 patients in POAG group and 30 eyes of 30 patients in healthy control (HCs) group were enrolled in the study. Groups were similar for age and gender distribution. Central LCT was significantly higher in OHT group, compared to HCs (333.8±50.5µm vs. 304.5±46.3µm, P=0.02) and POAG group (286.7±140.4, P=0.001). PLD and LCD were both highest in POAG (282.3±145.5µm and 471.3±195.2µm) followed by OHT (244.8±30.2µm and 440.7±18.7µm) and HCs(170.1±152.6 µm and 412.8±80µm), only the difference between POAG and HCs in PLD was statistically significant(P=0.03). PLTT, OD torsion, disc-foveal angle and disc-ovality showed no significant difference.

Conclusion: LC was significantly thicker in eyes with OHT, compared to POAG and HCs. This finding may be relevant to optic nerve protection from high intraocular pressure in patients with ocular hypertension.