Enhanced depth imaging optical coherence tomography of deep optic nerve complex structures in glaucoma

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Research

Background:

• Glaucoma is a progressive optic neuropathy characterized by damage to the optic nerve complex (ONC).
• Accurate assessment of deep ONC structures is crucial for understanding glaucoma pathophysiology.
• Traditional imaging methods may have limitations in visualizing these deep structures.

Purpose of the Study:

• To evaluate the utility of enhanced depth imaging (EDI) optical coherence tomography (OCT) for visualizing deep structures within the optic nerve complex in glaucoma patients.
• To assess the visibility and morphologic characteristics of structures like the lamina cribrosa and peripapillary vasculature using EDI OCT.

Main Methods:

• A prospective, observational study involving 73 glaucoma patients (139 eyes).
• Serial horizontal and vertical EDI OCT images of the ONC were acquired.
• Deep ONC structures, including lamina cribrosa (LC), short posterior ciliary arteries (SPCA), central retinal artery (CRA), central retinal vein (CRV), peripapillary choroid, sclera, and optic nerve subarachnoid space, were analyzed.

Main Results:

• EDI OCT visualized the anterior laminar surface in all eyes and LC pores in 76% of eyes.
• Focal LC defects corresponding to optic disc photograph lesions were identified.
• The CRA and CRV were visualized in all eyes, with distinct morphologic differences noted.
• SPCAs were visualized in 86% of eyes.
• The optic nerve subarachnoid space was visualized in 18% of eyes, particularly in those with high myopia.

Conclusions:

• EDI OCT is valuable for visualizing a broad range of deep ONC structures in glaucoma.
• The technology can aid in the detection, conceptualization, and understanding of in vivo anatomical and pathological features of the ONC in glaucoma.
• EDI OCT offers potential for improved diagnostic and research capabilities in glaucoma management.