Imaging of iris vasculature: current limitations and future perspective

Area of Science:

• Ophthalmology
• Medical Imaging
• Vascular Biology

Background:

• Traditional iris angiography methods (fluorescein and indocyanine green) are invasive and rarely performed, limiting understanding of iris vasculature.
• Optical coherence tomography angiography (OCTA) is a noninvasive technique for visualizing retinal and choroidal vasculature, now being applied to the iris.
• Current iris OCTA imaging lacks standardized protocols and interpretation guidelines for both healthy and diseased eyes.

Purpose of the Study:

• To review the application of OCTA for iris vasculature imaging.
• To discuss the challenges and artifacts associated with iris OCTA.
• To highlight potential future developments in iris OCTA technology.

Main Methods:

• Review of existing literature on OCTA applied to iris vasculature.
• Discussion of common artifacts in iris OCTA, including shadowing, motion, segmentation errors, and mirror effects.
• Analysis of how current OCTA device features (e.g., eye-tracking) impact anterior segment imaging.

Main Results:

• Iris OCTA provides detailed visualization of iris vasculature noninvasively.
• Identified artifacts can compromise image quality and interpretation.
• Ambient room lighting is recommended to induce miosis and stabilize iris vasculature during imaging.

Conclusions:

• Iris OCTA is a promising noninvasive tool for studying iris vasculature in health and disease.
• Standardization of imaging protocols and artifact mitigation are essential for clinical adoption.
• Future advancements, including dedicated eye-tracking systems and new OCTA metrics, could enhance iris imaging capabilities.