Three dimensional Optical Coherence Tomography (Swept Source OCT) of a healthy human choroid in the center of the retina (fovea). The picture shows converging vascular channels with their inner ceiling (violet) and outer ground (brown). In the center, a bridging, perpendicular tissue column is dividing the choroidal space. Blood cells are artificially inserted to illustrate the dimensions. The height of the imaged channels is about 100 micrometer, red blood cells about 8 micrometer.
In ophthalmology, the introduction of new, non-invasive and non-touch imaging modalities as Optical Coherence Tomography (OCT) has increased the visualization of the in vivo structures of the eye and provided crucial insights into the early diagnosis and monitoring of diseases. OCT can be compared to ultrasound. Instead of soundwaves, a coherent 1050nm laser light may be used to obtain 256 high resolution cross sectional images of a human retina. Images were speckle-noise freed with structural information preservation. The vessels were extracted from the 3D data stack using a semi-automatic rolling-marble method. From these data, a 3D digital model of the outer choroid was calculated. Colors and textures were added to highlight the choroidal walls.
The retina has a vital role in vision. Permanent blindess can be caused by damage to the retina in such diseases as diabetes, glaucoma or age-related-macular degeneration. The unique function of the retina is supported by the blood flow of which approximately 70 percent goes through the choroid. The choroid shows the highest perfusion of any tissue in the human body. The center most part of the retina is called fovea and is responsible for central, sharpest vision. This avascular fovea receives metabolites and oxygen to 100 percent from the choroidal circulation which emphasizes the extraordinary importance of the choroid.
