A Dynamic System With Parallel Detecting Mode Used For Pharmacokinetic Fluorescence Molecular Tomography

Nowadays,malignant tumor is a major public health problem.The cure rate can be improved tremendously by early diagnosis and intervention.Pharmacokinetic fluorescence molecular tomography(P-FMT),by describing the absorption,distribution,metabolism and excretion processes of fluorescence agent in vivo,has some potential applications in the fields of early tumor detection,staging and efficient evaluation.It's imperative for imaging system to measure quickly,in order to capture the fast-changing information of fluorescence during the finite metabolism process in vivo.Therefore,a dynamic system for P-FMT with parallel detecting mode is proposed combining lock-in photon-counting technique and the mode of muti-source and muti-detector.Besides.It predominates in high sensitivity,high spatial sampling density and high time sampling rate.In this paper,16 source fibers coupled with detection fibers are adopted to improve the spatial sampling density of the system to reduce the inherent ill-posedness of the algorithm.In the meanwhile,a frequency-encoded source system with 16 laser diodes(LD)and a digital lock-in-photon-counting detection system,are combined to achieve the parallel acquisition of data and dynamic measurement.Firstly,a series of prior experiments demonstrate good stability,ambient light suppression and low frequency crosstalk rate of the system.Secondly,static and dynamic phantom imaging experiments show the favorable imaging ability and metabolic rate resolution.Finally,experiment of liver Indocyanine Green(ICG)metabolism for healthy mouse proves the ability to capture the fast-changing fluorescence signals in small animals.Thus,it suggests the advanced utility for the further research of P-FMT on tumor.