Variable velocity range imaging of the choroid with dual-beam optical coherence angiography

• Published in: Optics Express Vol. 20; no. 1; pp. 385 - 396
• Main Authors: 安野 嘉晃, Jaillon Franck, Makita Shuichi, Yasuno Yoshiaki
• Format: Journal Article
• Language: English
• Published: United States Optical Society of America 02.01.2012
• Subjects: Angiography - instrumentation; Choroid - anatomy & histology; Choroid - blood supply; Ciliary Arteries - anatomy & histology; Equipment Design; Equipment Failure Analysis; Humans; Reproducibility of Results; Sensitivity and Specificity; Tomography, Optical Coherence - instrumentation
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/oe.20.000385

In this study, we present dual-beam Doppler optical coherence angiography with variable beam separation. Altering beam distance, independently of the scanning protocol, provides a flexible way to select the velocity range of detectable blood flow. This system utilized a one-micrometer wavelength light source to visualize deep into the posterior eye, i.e., the choroid. Two-dimensional choroidal vasculature maps of a human subject acquired with different beam separations, and hence with several velocity ranges, are presented. Combining these maps yields a semi-quantitative visualization of axial velocity of the choroidal circulation. The proposed technique may be useful for identifying choroidal abnormalities that occur in pathological conditions of the eye.