Lamina Cribrosa Thickness in Patients With Keratoconus.

Abstract

To evaluate the thickness and depth of lamina cribrosa (LC) in the optic nerve head region of the eyes in patients with nonglaucomatous keratoconus and to compare the thickness and depth with those of age-matched controls. This was a cross-sectional, observational study comprising 45 patients with keratoconus and 56 healthy subjects. Analysis of LC imaging was performed using spectral domain optical coherence tomography. Data collected included spherical equivalent, central corneal thickness, axial length, intraocular pressure, and keratometry. Eyes with keratoconus had significantly thinner LC (174.9 ± 11.4 vs. 249.1 ± 4.9 μm, P < 0.001) compared with control group eyes. There was no statistically significant difference in the depth of LC between the keratoconus and control groups (P = 0.3). Multivariable analysis, controlled for age and sex, showed that the thickness of LC significantly correlated with central corneal thickness (P < 0.001). This association persisted (P < 0.001) after controlling for intraocular pressure in addition to age and sex. There was no significant correlation with other factors, including the spherical equivalent (P = 0.93) and keratometry (P = 0.46). The results of this study showed that optical coherence tomography measurement of LC revealed thinner LC for patients with keratoconus compared with healthy controls. The structural properties of the cornea may be related to the optic nerve.