Systems with Magnetization Transfer (MT) are particularly sensitive to $$$B_1^+$$$ inhomogeneity, as the semisolid magnetization saturation is proportional to the square of $$$B_1^+$$$. This can be problematic at 7T imaging, where $$$B_1^+$$$ inhomogeneity is more severe, compromising the MT contrast obtained. This work proposes applying a composite MT prep-pulse with varying RF complex weights for each sub-pulse. These weights are optimized to deliver in the end a homogenous $$$\langle{}B_1^{+2}\rangle$$$, such that the MT contrast obtained is spatially uniform. Simulation and phantom results showed great improvement in the $$$\langle{}B_1^{+2}\rangle$$$ and MT ratio maps.
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