Research progress in multi-modality imaging system based on fluorescence molecular tomography / 国际生物医学工程杂志

Multi-modality imaging system based on fluorescence molecular tomography (FMT) has been widely used in animal studies.It combines FMT with other imaging modalities,which realizes the imaging of anatomical structure,physiological function and biological activities on molecular or cellular levels of small animal in vivo at the same time.This review gives an introduction to the history and current research status of singlemodality FMT system,introduces the developments of multi-modality system based on FMT,especially the system setup,working principle,performance and application of FMT/CT,FMT/MRI and FMT/radionuclide imaging.The prospects of multi-modality imaging system based on FMT are discussed.

3-D Image of Near-infrared Fluorescent Probe in Tissue-like Solution / 航天医学与医学工程

Objective To develop the fluorescence molecular imaging system and obtain the 3D images of near-infrared fluorescent probe in tissue-like solution.Methods Weak optical signals were acquired with hypothermal cooled CCD camera.The system captured the fluorescent images of different projections at rotating the tissue phantom.The photon propagation in tissue followed the diffusion approximation theory.The 3D image of probe was calculated with a fast reconstruction algorithm based on finite element approach.Results The imaging system could obtain the full-angle dense raw dataset.The reconstruction algorithm had capacity to recover the position and contour of the fluorescent target included in diffusive medium.Conclusion The results from phantom experiments are promising and show the potentials to act as a platform for in vivo fluorescence tomography.

A Reconstruction Algorithm for Fluorescence Molecular Tomography Based on the Total Least-Squares Rule and the Normalized Conjugate Gradient Method / 航天医学与医学工程

Objective To find an efficient and practical reconstruction algorithm for the fluorescence molecular tomography basing on total leastsquares rule as well as the normalized conjugate gradient method.Methods The finite element method was used to get the weighting matrix from the forward diffusion model.For the inverse reconstruction problem,the total least-squares rule was employed.The normalized conjugate gradient method was applied to find the fluorochrome information in the objective area.Results The simulation experiments showed that images reconstructed by the total least-squares rule were more accurate than those reconstructed by the least-squares rule under the same circumstances when noise existed.The presented algorithm could also give consistent results when the initial guesses varied in a wide range.Conclusion The algorithm presented in this paper offers a practical and efficient reconstruction for the fluorescence molecular tomography.