Non-invasive measurement of optical properties in coral tissue and skeleton using Inverse spectroscopic optical coherence tomography (ISOCT)

Reef-building corals are a vital part for the health and biodiversity of marine ecosystems. However, they are facing grave challenges from climate change. Despite the urgent need to understand the mechanism of light collection in corals, many key questions remain open largely due to the lack of techniques to measure the optical properties in live corals. Here we used a recently developed extension of OCT, Inverse Spectroscopic Optical Coherence Tomography (ISOCT), to image vast varieties of coral species, acquiring 4D cubes containing spectral information alongside 3D geometry. A full set of optical parameters that inherently linked with key optical components of coral are calculated in both coral tissue and skeleton. Using a spectroscopic OCT imaging system, our study expands current knowledge of coral physiology.