Sensitivity of susceptibility-weighted imaging in detecting superparamagnetic XXXX -labeled mesenchymal stem cells: a comparative study.

@entity1 @entity3538 @entity1933 @entity1188 @entity35
BACKGROUND: Susceptibility-weighted imaging (SWI) is extremely sensitive in the detection of superparamagnetic @entity1933 (SPIO) nanoparticle-labeled cells. However, no study has compared molecular imaging for stem cell detection using SWI and other MRI pulse sequences. OBJECTIVES: This study aims to assess the sensitivity of SWI in detecting SPIO nanoparticle-labeled, @entity1 bone marrow-derived mesenchymal stem cells (SPIO-hMSCs) compared with that of T2- and T2*-weighted imaging (T2WI and T2*WI, respectively) in a phantom and in vivo study in @entity35 . MATERIALS AND METHODS: A phantom was prepared with various cell concentrations. In one normal @entity35 , SPIO-hMSCs were implanted directly through burr holes into both caudate putamens, while in three @entity35 without and six @entity35 with @entity1188 , 2.5 * 10(5)/ml SPIO-hMSCs were infused into the @entity3538 (ICA). T2WI, T2*WI, and SWI findings were compared for dark regions representing SPIO-hMSCs. RESULTS: SWI and T2*WI detected 15   L of 13 SPIO-hMSCs/  L and 15   L of 27 SPIO-hMSCs/  L in the phantom, respectively and 3   L of 333 SPIO-hMSCs/  L and 3   L of 167 SPIO-hMSCs/  L in the normal @entity35 brain (direct implantation). In the normal @entity35 brain (ICA infusion), one of the three cases showed numerous foci of dark regions dispersed throughout the brain on T2*WI and SWI. Dark regions surrounded the @entity1188 in all six infracted @entity35 brains. The dark region was most prominent on SWI, followed by T2*WI and T2WI in all six @entity35 (P = 0.002). Implanted SPIO-hMSCs were confirmed using Prussian blue staining. CONCLUSIONS: SWI is the most sensitive in the detection of SPIO-hMSCs, with the dark regions representing SPIO-hMSCs being more prominent on SWI than on T2*WI and T2WI.
