Are optic nerve head and choroidal circulation affected by eye movements?

Area of Science:

• Ophthalmology
• Medical Imaging
• Neuroscience

Background:

• Horizontal eye movements can mechanically affect the optic nerve.
• Optical coherence tomography angiography (OCTA) is a recent technology for studying these effects.
• Previous research on OCTA and eye movements is limited.

Purpose of the Study:

• To investigate changes in OCTA data during horizontal eye movements (primary gaze, abduction, adduction) in healthy individuals.
• To assess the impact of gaze position on radial peripapillary capillary density (RPCD) parameters.

Main Methods:

• Prospective study involving 30 healthy volunteers (ages 15-73).
• OCTA (Angio Disc QuickVue) was used to examine radial peripapillary capillary density (RPCD) parameters.
• Measurements were taken in primary gaze, abduction, and adduction positions.

Main Results:

• A statistically significant difference was observed only in the superior hemifield of the left eye (P=0.032).
• All vessels' (AV) vessel density in the superior hemifield showed a relative decrease during adduction.
• No significant differences were found in other RPCD parameters or the right eye.

Conclusions:

• Short-term horizontal eye movements do not cause substantial changes in OCTA data in healthy individuals.
• The superior hemifield of the left eye may exhibit subtle alterations with horizontal gaze shifts.
• Findings suggest limited mechanical impact on optic nerve vasculature from typical eye movements.