Molecular imaging true color spectroscopic (METRiCS) optical coherence tomography
Optical coherence tomography (OCT) is a cross-sectional high-resolution optical imaging modality that operates under the principles of low coherence interferometry (LCI) to enable optical sectioning, or depth resolution, within a biological sample [1]. OCT has been particularly successful for application in ophthalmology where the optical transparency of the eye, especially for wavelengths in the near-infrared region of the spectrum, allows high-resolution visualization of retinal layers for diagnosing diseases and assisting in surgeries [2]. Although originally implemented in a time domain approach where mechanical scanning of a reference mirror in an interferometry scheme enabled measurement of depth resolved reflection profiles (A-scans), recent technological advances in OCT have led to the dominance of frequency domain (FD-) OCT due to its improved acquisition speed [3] and sensitivity [4]. As the name suggests, FD-OCT measures interferometric data as a function of frequency and a Fourier transform is used to produce the A-scan, typically with an axial resolution of a few micrometers and imaging depths of 1-2 mm. To implement tomographic images, multiple A-scans are obtained using transverse scanning or a parallel acquisition scheme.
