SWIFT detection of SPIO‐labeled stem cells grafted in the myocardium

Abstract

We report initial results from studies using sweep imaging with Fourier transformation (SWIFT) to detect superparamagnetic iron oxide (SPIO) particle-labeled stem cells in the rat heart. In experiments performed on phantoms containing titanium balls or SPIO-labeled cells, frequency-shifted signals surrounding the paramagnetic objects produced a pileup artifact visualized by SWIFT. Total signal intensity was retained to a much greater extent by SWIFT as compared to gradient echo imaging. SWIFT imaging of excised and in vivo hearts showed (a) reduced blooming artifact as compared with gradient echo imaging, which helped reduce ambiguity in the detection of SPIO-labeled cells; (b) enhancement of off-resonance signals relative to the background in the imaginary component of images; and (c) detailed myocardial anatomy in magnitude images, which provided anatomic reference. These features suggest SWIFT can facilitate the detection of SPIO-laden cells in the cardiovascular system.

Transplantation of Bone Marrow Mesenchymal Stem Cells for the Treatment of Type 2 Diabetes in a Macaque Model

“…Therefore, it is difficult for stem cell transplantation to meet the criteria of clinical applications. In recent years, with the development of molecular imaging, SPIO particles have been used as negative MR imaging (MRI) contrast agents for a variety of in vivo cell labeling applications and tracker studies following transplantation [Huang et al, 2007;Zhou et al, 2010]. This approach has given rise to a growing and wide range of interests.…”

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring

“…The subtraction method used in this work has been used by others, as well 28 . Other approaches include off resonance detection [29][30][31] , phase sensitive imaging that produces a particular pattern near SPIO voids 32 , and zero echo time image that uses T1 weighting to produce a positive signal intensity in the region of SPIO 33 . The advancement of these methods for improving quantitation of label, sensitivity and specificity is an area of active research today.…”

The Agfa Mayneord lecture: MRI of short and ultrashortT2andT2* components of tissues, fluids and materials using clinical systems

“…The images reflect both tissue MIOP concentration and deviations of the local magnetic field produced by the particles [50][51][52][53][54]. Techniques using SWIFT [55] and UTE [56][57][58] have also been successful for imaging MIOPs.…”

“…Contrast enhancement with gadolinium chelates may be seen within previously invisible tissues using UTE sequences [128], as well as with MIOPs [50][51][52][53][54][55][56][57][58]. Dental imaging has successfully identified caries [129][130][131].…”