Figure 2.

(a) Fluorescence singular decomposition (SVD) amplitude (arbitrary unit) for phantom experiments with different optical properties with the same Photofrin concentration (μ_a,ref = 0.64 cm⁻¹, μ_s,ref′ = 10 cm⁻¹). The fitting result of the corrected SVD_cor is depicted by the blue dotted curve. The dashed curves illustrate the fitting obtained using SVD (μ_a,ref, μ_s,ref′)/CF (μ_a, μ_s′). (b) Photofrin concentration calibration curve. (c) The validation of in vivo measured photosensitizer concentration using the contact probe (based on fluorescence spectroscopy) against the ex vivo measured Photofrin concentration.