Time Delay Estimation Between Retinal Arteries And Veins Pulsations Using Instantaneous Phase

Abstract

The eye fundus suffers from many diseases such as glaucoma, central retinal venous occlusion or intracranial pressure rise. The fundus examination by video-ophthalmoscope can diagnose and reveal the assumption of these diseases, for example, from dynamic changes in the vascular system. This paper focuses on the determination of time delay between signals extracted from vein and artery pulsations obtained by experimental video-ophthalmoscope. The signal is further processed and the instantaneous frequency is utilized for time delay estimation. The observed time delay is in the range of 0 to 233 ms, which is in accordance with published results.