title: Variable velocity range imaging of the choroid with dual-beam optical coherence angiography.
abstract: 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.
authors.affiliation: Computational Optics Group, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Franck
authors.initials: F
authors.lastname: Jaillon
authors.forename: Shuichi
authors.initials: S
authors.lastname: Makita
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Yasuno
mesh_terms: D000792:Angiography / Q000295:instrumentation*; D002829:Choroid / Q000033:anatomy & histology / Q000098:blood supply*; D019842:Ciliary Arteries / Q000033:anatomy & histology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000295:instrumentation*