Comparison of enhanced depth imaging and high-penetration optical coherence tomography for imaging deep optic nerve head and parapapillary structures

Abstract

PurposeTo evaluate and compare the abilities of enhanced depth imaging (EDI) and high-penetration optical coherence tomography (HP-OCT) to visualize the deep optic nerve head (ONH) and deep parapapillary structures.MethodsHorizontal and vertical optic nerve images were obtained using EDI-OCT and HP-OCT, during the same visit, from 24 eyes of 12 patients with glaucoma. Three graders, using a three-point grading system, independently graded the visibility of the deep ONH structures (prelaminar tissue surface, anterior laminar surface, posterior laminar border, and laminar pores) and deep parapapillary structures (intrascleral vessels, cerebrospinal fluid space, and parapapillary choroid). The differences in the visibility scores between the EDI-OCT and the HP-OCT images and among the image locations were analyzed statistically. The agreement in scoring among the graders also was analyzed.ResultsThe visibility of three ONH structures, the anterior laminar surface, posterior laminar border, and laminar pores, was significantly better with EDI-OCT (P = 0.0010, P < 0.0001, and P = 0.0141, respectively). In contrast, the visibility of all parapapillary structures was significantly better with HP-OCT (P < 0.0001, P = 0.0176, and P < 0.0001, respectively). The visibility scores were better in the vertical images compared with the horizontal images and were best in the temporal quadrants. The intergrader agreement was moderate for all parameters examined.ConclusionBoth EDI-OCT and HP-OCT are useful for evaluating the deep ONH and parapapillary structures. The visibility scores of the deep ONH structures were better with EDI-OCT, in contrast to the better visibility scores of the deep parapapillary structures with HP-OCT. Both systems should be chosen depending on the target tissue to observe.

Peripapillary Choroidal Thickness Analysis Using Swept-Source Optical Coherence Tomography in Glaucoma Patients: A Broader Approach

“…Statistically significant differences (p < 0.05) between both groups are italicized (Student t test). 12 large number of points in the peripapillary and other regions of the choroid [16][17][18] .…”

“…The longer wavelength facilitates deeper choroidal and scleral imaging, limiting light scattering at the photoreceptors and retinal pigment epithelium. It has been demonstrated that the visibility of parapapillary structures (intrascleral vessels, cerebrospinal fluid space, and parapapillary choroid) was significantly better with SS-OCT [16,17] .…”

Update on the Prevalence, Etiology, Diagnosis, and Monitoring of Normal-Tension Glaucoma

“…In addition, swept-source OCT uses the light source of a wavelength-sweeping laser centered at 1050 nm, which enables visualization of deeper structures such as the lamina cribrosa, choroid, and sclera. 99 Unknown glaucomatous changes occurring in these deep structures have been explored by swept-source OCT along with SD-OCT in the enhanced depth imaging mode. 100,101 Using new technologies, we expect additional NTG-specific features will be discovered.…”

Enhanced Depth Imaging of Central Laminar Thickness in Optic Neuropathy: Comparison with Normal Eyes

“…Consequently, EDI-OCT has been used to identify laminar changes in glaucomatous optic neuropathy (GON). [8][9][10][11] A pilot study by Park et al compared EDI-OCT-measured LTs between normal, primary open-angle glaucoma (POAG), and normaltension glaucoma (NTG) eyes, and found that laminar thicknesses (LTs) of both POAG and NTG eyes were significantly thinner than those of normal eyes. 12 However, if GON affects LT, the sources responsible for interrupted axoplasmic flow in non-GON may also cause alterations in the LC.…”