Recovery of Intrinsic Fluorescence From Single-Point Interstitial Measurements for Quantification of Doxorubicin Concentration

Department of Imaging Sciences, University of Rochester Medical Center, Rochester, New York, 14642.
Lasers in Surgery and Medicine (Impact Factor: 2.62). 08/2013; 45(8). DOI: 10.1002/lsm.22166
Source: PubMed


We developed a method for the recovery of intrinsic fluorescence from single-point measurements in highly scattering and absorbing samples without a priori knowledge of the sample optical properties. The goal of the study was to demonstrate accurate recovery of fluorophore concentration in samples with widely varying background optical properties, while simultaneously recovering the optical properties.
Tissue-simulating phantoms containing doxorubicin, MnTPPS, and Intralipid-20% were created, and fluorescence measurements were performed using a single isotropic probe. The resulting spectra were analyzed using a forward-adjoint fluorescence model in order to recover the fluorophore concentration and background optical properties.
We demonstrated recovery of doxorubicin concentration with a mean error of 11.8%. The concentration of the background absorber was recovered with an average error of 23.2% and the scattering spectrum was recovered with a mean error of 19.8%.
This method will allow for the determination of local concentrations of fluorescent drugs, such as doxorubicin, from minimally invasive fluorescence measurements. This is particularly interesting in the context of transarterial chemoembolization (TACE) treatment of liver cancer. Lasers Surg. Med. © 2013 Wiley Periodicals, Inc.

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