Introduction B1 inhomogeneity in a human body increases as the strength of static magnetic field increases and the RF wavelength becomes smaller. Recently, various RF control methods have been developed to reduce B1 inhomogeneity. For example, some methods involve devices such as dielectric pads [1,2] or coupling coils [3,4], or techniques such as B1 shimming [5,6]. However, B1 inhomogeneity st...

Transmit SENSE. For this purpose, an ROI was drawn in the occipital lobe (white ROI Fig3) and two B1 Phase Shim solutions were calculated and applied in order to obtain an homogeneous B1 magnitude within this ROI: one based on the estimated B1 maps, another one based on the measured B1 maps. As can be seen in Fig3 (in degrees), both B1 Shim sets produced tremendous improvement in B1 efficiency ...

Let A be a non empty set, let B be a set, let B1 be a set, and let y1 be a function from B1 into A. Let us assume that B1 ⊆ B. The functor cylinder0(A,B,B1, y1) yields a non empty subset of A B and is defined by: (Def. 1) cylinder0(A,B,B1, y1) = {y : B → A: y B1 = y1}. Let A be a non empty set and let B be a set. A non empty subset of AB is said to be a thin cylinder of A and B if: (Def. 2) The...

6,123,819 A * 9/2000 Peeters ....................... 204/452 6,361,958 B1 * 3/2002 Shieh et al. ................. 435/7.1 6,524,790 B1 * 2/2003 Kopf-Sill et al. .............. 435/6 6,585,939 B1 7/2003 Dapprich 6,599,436 B1 7/2003 Matzke et al. 6,613,512 B1 9/2003 Kopf-Sill et al. 6,649,358 B1 * 11/2003 Parce et al. .................. 435/7.2 6,699,665 B1 * 3/2004 Kim et al. ......................

Introduction: At very high magnetic field, strong B1 heterogeneities occur in human MR images as RF wavelength becomes equal to, or smaller than, the size of the imaged target, interacting with lossy and dielectric properties of biological tissues(1,2). Different RF Shim techniques can be used in order to mitigate B1 inhomogeneities, which have considerable differences in their respective hardw...