Abstract
Purpose :
To develop and evaluate a method for acquiring electrocardiography (ECG) coupled optical coherence tomography (OCT) data, aiming to understand blood flow propagation from the heart to the retina, and to introduce the heart-retina time (HRT) as a potential biomarker for cardiovascular health.
Methods :
We developed a method to record time-resolved dynamic OCT B-scan images and ECG signals synchronously. Time-resolved dynamic OCT was acquired at the optic nerve head of five healthy subjects. The B-scans of the OCT time series were registered on each other using rigid body transformations and synchronised with the ECG data through timestamps with milliseconds precision. The centres of the arterioles were manually annotated on each B-scan, and adjacent subvolumes were then extracted. Blood flow velocity profiles within the arterioles were determined using fringe washout analysis. The HRT was calculated using signal cross-correlation between the R-Peak in the ECG and the sharpest rise in the retinal flow-velocity profile.
Results :
Synchronous ECG and OCT acquisition was successfully performed in all five included subjects, demonstrating the feasibility of this technique, and confirming previously found pulsatile blood flow profiles. The cross-correlation of the ECG and the blood flow profiles in retinal arterioles revealed the propagation of the blood column within a cardiac cycle, with a HRT of 144 ± 19 ms (mean ± SD). The method showed good reproducibility with an intrasubject coefficient of variation of 0.11 ± 0.03 and an intersubject coefficient of variation of 0.09.
Conclusions :
The synchronised acquisition of ECG with dynamic OCT offers a method to explore cardiovascular and ocular health interconnections. This study establishes the foundation for utilising the HRT as a potential biomarker in evaluating systemic and ocular vascular conditions.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.