In vivo measurement of anterior chamber pulsation in healthy subjects using full-range complex spectral domain optical coherence tomography

Abstract

A pulsation measurement algorithm was presented in this study, by using the phase-based method to visualize ocular pulse in the anterior chamber of healthy eyes. The algorithm mainly tracks the relative displacement between the cornea and lens by extracting the phase difference between adjacent images separated by 5 ms time intervals. The anterior chamber structural image in vivo is achieved by full-range, complex spectral domain, optical coherence tomography (FRC SD-OCT). Phase tracking was performed on a total of 1000 images within 5 s. In order to eliminate the noise phase caused by human motion during the acquisition process, the high-order phase compensation algorithm was used to eliminate the phase motion of large tissues. The frequency of the phase change in the relative motion after the noise subtraction was 1.2 Hz. Comparing with the heart beat measured by a finger pulse oximeter at the same time, the frequency of the phase change was consistent with the heart beat frequency. This measurement technique can be used to evaluate the biomechanical properties of ocular tissue and has a positive effect on the pathological studies of glaucoma.