Retinal Microvascular Network and Microcirculation Assessments in High Myopia

Area of Science:

• Ophthalmology
• Medical Imaging
• Vascular Biology

Background:

• High myopia is a significant risk factor for various ocular pathologies.
• Understanding changes in the retinal microvasculature is crucial for managing myopia-related complications.

Purpose of the Study:

• To investigate alterations in the retinal microvascular network and microcirculation in individuals with high myopia.
• To quantify changes in vessel density and blood flow velocity in high myopic eyes.

Main Methods:

• A cross-sectional, comparative study involving 20 high myopia subjects and 20 age- and sex-matched controls.
• Optical coherence tomography angiography (OCTA) was used for retinal microvascular imaging and fractal analysis (box counting) to assess vessel density.
• Retinal Function Imager assessed retinal microvessel blood flow velocity (BFV), with corrections for ocular magnification.

Main Results:

• Significantly decreased microvessel density in both superficial and deep vascular plexuses in the high myopia group compared to controls.
• Microvessel density was negatively correlated with axial length in myopic eyes.
• No significant differences in retinal microvessel blood flow velocity (BFV) were detected between groups.

Conclusions:

• High myopia is characterized by a reduction in retinal microvascular density, likely due to ocular elongation.
• Retinal microvessel blood flow velocity remains unchanged, suggesting a primary vascular network alteration.
• Quantitative OCTA analysis offers a potential tool for characterizing myopia pathophysiology and enabling early detection of related retinopathy.