Abstract
Introduction
Optical coherence tomography (OCT) uses laser interferometry for non-invasive cross-sectional imaging of tissues with micrometer resolution. This technology is therefore ideal to visualize the micro-structures of the human retina and choroid in vivo. Additionally blood flow can be detected from Doppler frequency shifts in the OCT signal over time, which are caused by moving particles in flowing blood. In this study we investigated if these Doppler shifts can be used to create angiograms of the retina and choroid.
Methods
An experimental OCT system was constructed based on a 1040 nm swept laser source. A healthy volunteer was imaged over a retinal area of 6.0 × 7.9 mm 2 (20º × 26º). Doppler shifts were evaluated by measuring each location twice and were calculated from phase changes within the OCT signals. Angiograms of the vasculature were created by integration of the phase changes over depth.
Results
The retinal angiogram (Fig. 1(A)) shows blood vessels (in white) down to the capillary level and visualizes clearly the avascular zone of the fovea and the entrance and exit of vessels through the optic disc. The choroidal angiogram (Fig. 1(B)) shows a dense network of large vessels below the retina.
Conclusions
Doppler OCT can produce high-resolution angiograms of the retina and choroid.
Optical coherence tomography (OCT) uses laser interferometry for non-invasive cross-sectional imaging of tissues with micrometer resolution. This technology is therefore ideal to visualize the micro-structures of the human retina and choroid in vivo. Additionally blood flow can be detected from Doppler frequency shifts in the OCT signal over time, which are caused by moving particles in flowing blood. In this study we investigated if these Doppler shifts can be used to create angiograms of the retina and choroid.
Methods
An experimental OCT system was constructed based on a 1040 nm swept laser source. A healthy volunteer was imaged over a retinal area of 6.0 × 7.9 mm 2 (20º × 26º). Doppler shifts were evaluated by measuring each location twice and were calculated from phase changes within the OCT signals. Angiograms of the vasculature were created by integration of the phase changes over depth.
Results
The retinal angiogram (Fig. 1(A)) shows blood vessels (in white) down to the capillary level and visualizes clearly the avascular zone of the fovea and the entrance and exit of vessels through the optic disc. The choroidal angiogram (Fig. 1(B)) shows a dense network of large vessels below the retina.
Conclusions
Doppler OCT can produce high-resolution angiograms of the retina and choroid.
| Original language | English |
|---|---|
| Pages | 35-35 |
| Number of pages | 1 |
| Publication status | Published - 8 Mar 2013 |
| Event | VU University Medical Center Science Exchange Day - VU University Medical Center, Amsterdam, Netherlands Duration: 8 Mar 2013 → 8 Mar 2013 |
Conference
| Conference | VU University Medical Center Science Exchange Day |
|---|---|
| Abbreviated title | VUmc SED 2013 |
| Country/Territory | Netherlands |
| City | Amsterdam |
| Period | 8/03/13 → 8/03/13 |
Keywords
- optical coherence tomography
- ophthalmic imaging
- angiography