Enhanced depth imaging detects lamina cribrosa thickness differences in normal tension glaucoma and primary...

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Research

Background:

• The lamina cribrosa's structure is crucial in glaucoma pathogenesis.
• Standard imaging modes may have limitations in visualizing subtle structural changes.
• Enhanced depth imaging (EDI) offers potential for improved visualization.

Purpose of the Study:

• To evaluate the superiority of EDI mode over standard mode for lamina cribrosa imaging using Heidelberg Spectralis SD-OCT.
• To compare lamina cribrosa thickness in different glaucoma subtypes and controls.
• To investigate the impact of disc hemorrhage on lamina cribrosa thickness in normal tension glaucoma (NTG).

Main Methods:

• A cross-sectional, case-control study included 137 glaucoma patients and 49 healthy controls.
• Optic nerve head B-scans were acquired using both standard and EDI modes of Spectralis SD-OCT.
• Laminar thickness was measured in superior, central, and inferior regions; reproducibility was assessed.

Main Results:

• EDI OCT imaging demonstrated superior intra- and inter-observer and visit reproducibility compared to standard imaging.
• Significantly thinner laminar thickness was observed in primary open-angle glaucoma (POAG) and NTG groups versus controls.
• Patients with NTG and disc hemorrhage exhibited thinner laminar regions than NTG patients without disc hemorrhage.

Conclusions:

• The EDI mode of Spectralis SD-OCT effectively differentiates lamina cribrosa characteristics across glaucoma types.
• Lamina cribrosa thickness is reduced in NTG eyes, particularly in those with associated disc hemorrhage.