Doppler OCT is an adaptation of optical coherence tomography that measures motion-induced phase shifts in the OCT signal to estimate blood flow in ocular vessels. It combines structural and flow information in a single scan.
Technique
By analysing changes in the OCT signal between repeated scans, Doppler algorithms calculate velocity components along the beam direction. When combined with vessel geometry, this can provide estimates of volumetric blood flow.
- Capable of visualising flow in retinal and choroidal vessels
- Non-invasive and dye-free
- Sensitive to motion artefacts and requires stable fixation
- Angle between beam and vessel affects accuracy of velocity measurements
Applications
Doppler OCT is used mainly in research to study ocular blood flow in glaucoma, diabetic retinopathy, and other vascular conditions. It may eventually help characterise haemodynamic changes and guide therapy.
- Offers repeatable quantitative flow indices under standardised conditions
- Can be combined with structural metrics for comprehensive assessment
- Technical challenges currently limit widespread clinical use
- Ongoing development aims to improve robustness and ease of interpretation
