Automatic segmentation of the optic nerve head for deformation measurements in video rate optical coherence tomography

Abstract

Optical coherence tomography (OCT) imaging has become a standard diagnostic tool in ophthalmology, providing essential information associated with various eye diseases. In order to investigate the dynamics of the ocular fundus, we present a simple and accurate automated algorithm to segment the inner limiting membrane in video-rate optic nerve head spectral domain (SD) OCT images. The method is based on morphological operations including a two-step contrast enhancement technique, proving to be very robust when dealing with low signal-to-noise ratio images and pathological eyes. An analysis algorithm was also developed to measure neuroretinal tissue deformation from the segmented retinal profiles. The performance of the algorithm is demonstrated, and deformation results are presented for healthy and glaucomatous eyes.

Quantitative Optical Coherence Elastography of the Optic Nerve Head In Vivo

“…Although the mechanism of glaucoma is not clear, it is most likely that the central pathophysiology is caused by the damage of RGC axons of the optic nerve head (ONH) [3] . The ONH has attracted much attention for its unique discontinuity in the cornea-scleral shell which bears the dynamic load or force in the mechanical systems [4,5] . Elevated intraocular pressure (IOP) has been seen to be the primary risk factor for the progression of glaucoma.…”

Quantitative confocal optical coherence elastography for evaluating biomechanics of optic nerve head using Lamb wave model

“…3 The ONH is a region of special biomechanical interest because it is a discontinuity in the cornea-scleral shell, and this type of discontinuity typically gives rise to stress or strain concentrations in mechanical systems. 4,5 The mechanical properties of the ONH are dependent on the interaction of its individual components. At low stress, it is likely that the elastin component allows for an initially large volume change formed by the distending ONH and, as pressure increases and the extended collagen fibers limit further deformation, the ONH becomes progressively stiffer.…”