[A new approach for studying the retinal and choroidal circulation]

Area of Science:

• Ophthalmology and Biomedical Engineering
• Advanced imaging techniques for ocular circulation assessment
• Computer-assisted analysis of retinal and choroidal vasculature

Context:

• Traditional methods for evaluating ocular circulation have limitations in throughput and detail.
• Indocyanine green (ICG) video angiography and spectral retinal imaging are key technologies for fundus circulation studies.
• Computer technology offers new avenues for analyzing complex vascular and physiological data from the eye.

Purpose:

• To reevaluate and improve indocyanine green (ICG) video angiography for better visualization of choroidal circulation.
• To develop and apply computer technology for analyzing ICG angiograms.
• To introduce a novel spectral retinal imaging system for measuring fundus oxygen saturation levels.

Summary:

• Developed an improved ICG video system with dual light sources (780 nm and 805 nm) based on ICG's spectral absorption and binding properties.
• Analyzed residual ICG fluorescence in age-related macular degeneration (ARMD) and normal subjects, identifying hypofluorescent lesions in ARMD.
• Characterized choroidal dye filling patterns and developed computer-assisted analysis for dynamic flow evaluation, and validated a spectral retinal imaging system for measuring retinal oxygen saturation in healthy volunteers and patients with retinal circulatory disturbances and glaucoma.

Impact:

• The enhanced ICG angiography system provides precise evaluation of choroidal circulation dynamics, aiding in the study of diseases like central serous chorioretinopathy.
• The spectral retinal imaging system offers a non-invasive, reproducible clinical tool for assessing retinal ischemia in conditions such as central retinal vein occlusion and glaucoma.
• These advancements in imaging technology contribute to improved diagnosis and understanding of various chorioretinal diseases.