Peter Roland Seevinck1, Gopal Varma2, Hendrik de Leeuw1, Julien Senegas3, Tobias Schaeffter2, Chris J.G. Bakker1
1Imaging Sciences Institute, Department of Radiology , University Medical Center, Utrecht, Netherlands; 2Division of Imaging Sciences, King's College London, UK; 3Philips Research Europe, Hamburg, Germany
The potential of susceptibility gradient mapping (SGM) for the selective depiction of holmium-loaded microspheres (HoMS) in the liver in ex vivo and in vivo animal models was investigated and confirmed. It was shown that positive contrast can be optimized by varying the echo time. Although SGM is not sensitive to the origin of the induced d affect, directional information (i.e. 1D and 2D SG maps) can be used to exclude macroscopic field variations along the direction of choice. This allows discriminating between T2* effects induced by paramagnetic substances (local d) and macroscopic field inhomogeneities.