Micro-aneurysms in the retina

Cellular flow in 3D reconstructed retinal micro-aneurysm

Problem

Retinal micro-aneurysms are central to diabetic retinopathy progression, but local blood-cell mechanics are difficult to resolve experimentally in vivo. I examined how geometry and red-cell stiffness influence flow stresses and platelet transport.

Approach

  • Segment patient-derived retinal micro-aneurysm geometries from adaptive optics OCT data.
  • Generate geometry variants with different neck widths for sensitivity analysis.
  • Simulate pulsatile whole-blood flow with altered red-cell membrane stiffness.
  • Quantify wall shear stress, shear gradients, and platelet/RBC transport patterns.

Key finding

Both neck geometry and red-cell stiffness significantly changed local stress distributions and particle penetration behavior. Stiffer RBCs increased average shear-related metrics and altered margination trends.

Why it matters

These mechanisms provide a more detailed flow-based explanation for disease progression signals that are otherwise hard to isolate clinically.

Outputs

  • Publication details are listed in the References section below.
  • Geometry and flow field visualizations are provided on this page.

References

2022

  1. The effect of stiffened diabetic red blood cells on wall shear stress in a reconstructed 3D microaneurysm
    Benjamin Czaja, Jonathan Bouter, Morgan Heisler, and 5 more authors
    Computer Methods in Biomechanics and Biomedical Engineering, 2022