The visualization of the microvasculature yields an easily accessible and intuitive way to assess its integrity. During the last years, a number of strategies for contrasting microvasculature based on FDOCT have been introduced. Contrast between flow and static tissue can be obtained by determining changes either between -scans or successive tomograms in phase, a method known as phase variance,4 or in amplitude, known as speckle variance,5 or by filtering the complex spectrum, known as OMAG.6 Approaches based on phase difference between two spatially separated beams on the retina yielded good contrast of the retinal and choroidal vessel beds over a large range of velocities.7 Other authors introduced a pure intensity-based method to filter out capillaries from high resolution data thus avoiding axial decorrelation artifacts below vessels usually present in variance-based contrasting techniques.8 Generally, the demonstration of these techniques was restricted to small FOV because of limited acquisition speed. It was partially solved by stitching small volumes together.3 A critical point, however, concerning the clinical acceptance of this technique is certainly the associated long total measurement time, because of fixation change and the recording of redundant overlap areas required for registration. Ultrahigh-speed FDOCT is therefore a promising candidate to compete with the FOV and resolution of FA, since a large patch can be covered by a single recording in a few seconds. A rough estimation of the required imaging speed, taking into account a spatial sampling of , 5-fold redundancy for variation calculation, and a total acquisition time shorter than 10 s, shows that an -scan rate over 1 MHz is required. Recent developments in this imaging speed range are dominated by swept source (SS) systems. Over the last years, multi-MHz imaging was introduced based on the concept of Fourier domain mode locked (FDML) swept sources. Retinal and choroidal imaging with this technology at ultrahigh-speed was demonstrated at a center wavelength of 1060 nm.9 Posterior segment OCT imaging in that water window has the advantage of providing increased penetration into the choroid compared to the common 850 nm region because of reduced scattering. It allows for a better assessment of choroidal vasculature that is particularly important for ocular diagnosis; its network being the main oxygen and nourishment supplier of the retina.