<title>Comparative study of optical coherence tomography, photoacoustic technique, and time-of-flight technique in phantom measurements</title>

Abstract

of biomedical imaging techniques, the optical coherence tomography (OCT), photoacoustic (PA) and time-of-flight (TOF) techniques are among the most researched and, consequently, increasingly broadly applied. This article reviews their basic principles, compares their technical aspects and discusses their ability to determine optical parameters. Also studied is their applicability to non-invasive glucose monitoring in Intralipid^TM phantom measurements, followed by a discussion of some detected problems. Although suffering from a limited probing depth, OCT was found to have the best capacity for detecting changes in the light scattering properties of Intralipid^TM. Photon migration studies with the TOF technique showed changes in pulse amplitude, pulse width and arrival time of the pulse maximum as a function of changes in Intralipid^TM concentration, whereas the sensitivity of the PA technique for detecting changes in scattering was less pronounced. However, each technique showed changes in the registered signals when measuring large glucose concentrations in Intralipid^TM phantoms. Measurement results were also affected by the varying measurement geometries and the photon energies of the light sources.