Choroidal Imaging with Swept Source Optical Coherence Tomography – A Review

Abstract

The choroid provides up to 70 % of blood and oxygen to the eye. Pathological changes of this vascular tissue may lead to malnutrition of the retina and therefore be involved in the pathogenesis of numerous retinal disorders. Swept source optical coherence tomography (SS-OCT) is a new development of a non-invasive imaging technique that uses a tunable laser source with a higher wavelength light than conventional spectral domain OCT (SD-OCT). This enables visualisation of tissues below the retinal pigment epithelium. Thanks to SS-OCT’s ultrahigh speed and ultrahigh resolution it is possible to assess choroidal layers as well as to automatically create 3D maps of its thickness and volume. This review is to discuss how SS-OCT has improved our understanding of choroidal anatomy and function in various retinal and chorioretinal diseases. In future, detailed evaluation of choroid may play a crucial role in the diagnosis and management of various retinal diseases.