Fig. 1
From: Empirical retinal venous pulse wave velocity using modified photoplethysmography
Selected optic disc frame sequence captured during modified ophthalmodynamometry. The inferior retinal vein, initial contraction A– C and dilation of the segment D–F. Time was measured from pulse oximetry audio signal. At 120 frames per second (s) each frame represents approximately 0.008333 s. The total contraction time of the inferior retinal vein was estimated at 0.424983 s