Visualization of PDD Sensitizer's Concentration using Fourier Domain Optical Coherence Tomography

摘要

Recently, Fourier-Domain Optical Coherence Tomography (FDOCT), which is a spectral interferometer having a high speed scanning system, has been improved as 3-dimensional micro imaging technique. This has attracted the attention of medical scientists as a promising system of early cancer detection. It, however, has been difficult to quantitatively detect tumor lesion and its malignancy, because interference signals could be dependent on optical properties of biological tissue. In this study, we propose a tumor detection system based on FDOCT and oncotropic dye, namely Fourier-Domain Optical Coherence Dosimetry (FDOCD). OCT signals have the information of absorption by oncotropic dye as well as scattering from tissue, which are separately extracted by Windowed Inverse FFT corresponding to wavelength bands of interest. Therefore, FDOCD can simultaneously obtain two optical kinds of tomography, i.e. absorption profile as disease demarcation and scattering profile from morphologic distribution. In the present report, the calibration experiment was carried out to verify separate detection of scattering and absorbance. As a result, it indicated that FDOCD could determine the distribution of scatterer density, eliminating the signal degradation by optical absorption, e.g. drug concentration. It was suggested that FDOCD could separately and quantitatively monitor scatterer density and drug concentration.