Patent ID: 8624593

Claim:
A method for determining sensitivity matrices for hotspots for later use during determination of control signal sequences for individually-controllable antenna elements of a radio-frequency transmit system of a magnetic resonance tomography device, the method comprising: grouping, by a computer, a plurality of voxels of an object into clusters; assigning each of the clusters to a hotspot; and establishing a sensitivity matrix for each of the hotspots such that, in relation to each voxel of the cluster assigned to the hotspot, the difference between the sensitivity matrix established for the hotspot and a sensitivity matrix for the voxel is positive semi-definite, wherein, for each hotspot, elements of the sensitivity matrix represent the sensitivities of the hotspot of the object, the object being located in an area of influence of the radio-frequency transmit system on respective elements of a cross-correlation matrix, wherein the cross-correlation matrix contains elements that are the product of one of a number of antenna element values and the conjugated complex of one of the antenna element values, and wherein each of the antenna element values is characteristic of a control signal of an antenna element at a specific time so that for each hotspot, an SAR element is establishable by summing the products of the elements of the sensitivity matrix with the corresponding elements of the cross-correlation matrix.