Anterior lamina cribrosa surface depth in healthy Saudi females

This study was conducted to determine normative profile of anterior lamina cribrosa surface depth (ALCSD) in healthy Saudi females using Topcon Three-Dimensional (3D) Optical Coherence Tomography (OCT) 2000 - Spectral Domain (SD-OCT). In addition, the correlation between ALCSD and other clinical factors such as age, refractive error, intraocular pressure (IOP), central corneal thickness, anterior chamber depth, axial length, retinal nerve fiber layer thickness, and disk area was also assessed.

This study was a prospective, nonrandomized, cross-sectional, observational, and quantitative study.

This study included 191 eyes of 191 healthy Saudi females from the College of Applied Medical Sciences of King Saud University. Stereoscopic disk photographs were reconstructed using Topcon 3D OCT-2000 for all subjects. ALCSD was measured at three planes (superior, middle, and inferior) and defined as the distance from Bruch's membrane opening level (reference line) to anterior lamina cribrosa surface. Average of ALCSD at all planes was defined as mean ALCSD of the eye. Correlation between ALCSD and all the clinical factors was performed by linear regression analysis. Paired t-test was performed in order to compare ALCSD at all planes.

In this study, the average ALCSD was 371.88±114.62 μm (range, 155-647.6 μm). Paired t-test showed a significant difference between superior and middle planes (P=0.004) and middle and inferior planes (P=0.013). Using the same test, no significant difference between superior and inferior planes (P=0.820) was observed. Generally, the largest ALCSD was in the middle plane. In addition, linear regression analysis showed no significant correlation between ALCSD and associated clinical factors.

This work is the first to provide the normative profile of ALCSD in Saudi females using Topcon 3D OCT-2000. Further studies are recommended for males, different ethnic populations, high myopic eyes, and different age groups using advanced imaging techniques such as enhanced depth imaging OCT.