BIOMECHANICAL DEFORMATION OF THE LAMINA CRIBROSA IN HEALTHY AND GLAUCOMATOUS EYES

Abstract

Glaucoma is characterized by retinal ganglion cell axon (RGC) damage in the lamina cribrosa (LC). Once thought to be associated with elevated levels of intraocular pressure (IOP), glaucoma does not always develop at high IOP. Since IOP is clearly not the only risk factor in the development and progression of the disease, we have hypothesized that the biomechanics of the LC plays a central role in indicating the IOP levels that can be sustained before development of glaucoma.

Our objective is to use optical coherence tomography based 3-dimensional (3-D) strain-mapping technology to characterize IOP-induced biomechanical response of the LC in normal and glaucomatous human eyes in vivo. We show that the LC strains 1) are nonlinear; 2) exhibit regional variations in some glaucoma eyes; 3) trabeculectomy in glaucoma subjects relieved strain in the LC tissues. We additionally investigate the association of visual field parameters with the biomechanical changes in the LC.