Purpose: To describe a method for measuring the diameters of large retinal blood vessels by means of spectral domain optical coherence tomography.
Methods: Prospective cohort study of 29 healthy subjects (58 eyes) who underwent a spectral domain optical coherence tomography examination. Two cubes of horizontal scans were placed at the superior and inferior borders of the disk to include the large temporal retinal vessels. Vessels diameters were measured, and an artery-to-vein ratio was calculated at 10 measurement points (480-1440 μm superiorly and inferiorly from the optic disk border).
Results: The mean age of the study subjects was 41.45 ± 15.53 years. Patients had no ocular or systemic pathologies. The mean diameter of the retinal artery was 135.73 ± 15.64 μm and of the vein 151.32 ± 15.22 μm at the measurement point of 480 μm, with a gradual decrease to 123.01 ± 13.43 μm and 137.69 ± 13.84 μm, respectively, at 1440 μm. The artery-to-vein ratio was ≈ 0.9 at all points of measurement.
Conclusion: This is a new noninvasive method for retinal blood vessels diameter measurement using the spectral domain optical coherence tomography imaging modality. This method may aid in evaluation of retinal and systemic vascular diseases.