chapter  10
Molecular Contrast Optical Coherence Tomography
ByOscar Carrasco-Zevallos, Joseph A. Izatt
Pages 26

Optical coherence tomography (OCT) is a well-developed imaging modality that achieves structural imaging of tissue via interferometric detection of backscattered light [1]. Because of its high-resolution tomographic imaging, OCT was quickly adopted by ophthalmologists aer its inception in 1991. Ever since, OCT has revolutionized the eld of ophthalmology and is now the gold standard retinal imaging modality. OCT structural imaging enables the visualization of tissue with micron-scale resolution by probing refractive index discontinuities. However, because the real part of the refractive index does not vary signicantly among molecular species, OCT has inherently poor molecular contrast. Akin to CT/PET imaging, simultaneous structural and molecular OCT imaging may allow for more complete diagnostic analysis, since many pathological processes stem in biochemical abnormalities before progressing to structural deformations.