A Workflow for Three-Dimensional Reconstruction and Quantification of the Monkey Optic Nerve Head Vascular Network

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Medical Imaging

Background:

• A detailed understanding of the optic nerve head (ONH) vascular network is essential for eye physiology and pathology.
• Current in vivo imaging lacks the resolution and depth to fully characterize deep ONH vasculature.

Purpose of the Study:

• To develop and validate a workflow for 3D reconstruction and quantitative morphological analysis of the ONH vascular network.
• To provide a foundational dataset for understanding blood flow and oxygenation in the ONH.

Main Methods:

• Perfusion labeling of vessels in a normal monkey ONH.
• Simultaneous imaging using fluorescence microscopy (FM) and instant polarized light microscopy (IPOL).
• 3D reconstruction via image registration, segmentation, and skeletonization of the vascular network.

Main Results:

• Successfully reconstructed a 3D vascular network with 12,966 segments, 7989 branching points, and 1100 terminal points.
• Quantified vessel length, tortuosity, inclination (θ), and polar orientation (φ).
• Vessel length followed a lognormal distribution, tortuosity an exponential decay, with primary orientation towards the coronal plane.

Conclusions:

• The developed workflow enables detailed 3D eye-specific reconstruction and quantification of the monkey ONH vascular network.
• This methodology is a critical step towards analyzing ONH blood flow and oxygenation.
• Understanding vascular dysfunction in the ONH is key to investigating diseases such as glaucoma.