Effects of the time dependence of a bioluminescent source on the tomographic reconstruction.
There are two goals in this simulation study: (1) to show that the time variation of the bioluminescence source can cause artifacts in the tomographic images such that quantification and localization becomes impossible; and (2) to show that the a priori knowledge of the light kinetics can be used to eliminate these artifacts. These goals are motivated by the fact that the half-life of luciferase has been reported as 30 min to 2 h in vivo. We perform two-dimensional simulations. We consider a 40 mm diameter circular region with an inclusion of 6 mm diameter located 10 mm away from the center. The measurement data is simulated using a finite-element-based forward solver. We model the noncontact measurements such that four-wavelength data is collected from four 90 degrees apart views. The results show that the ratio of the total imaging time to the half-life of the exponentially decaying bioluminescent source is the deciding factor in the reconstruction of the source. It is also demonstrated that a priori knowledge of the source kinetics is required to perform tomographic bioluminescence imaging of short half-life bioluminescent sources and the use of spatial a priori information alone is not adequate.
Burcin Unlu
Mehmet
M
Tu and Yuen Center for Functional Onco-Imaging, University of California, Irvine, California 92697, USA. munlu@uci.edu
Gulsen
Gultekin
G
D000465:Algorithms; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008163:Luminescent Measurements / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors; D041622:Tomography, Optical / Q000379:methods*