Shimming procedure that includes determination of the target field by optimization in a parameter space of reduced dimensionality
US9817097B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 2014 |
| Grant date | Nov 14, 2017 |
| Priority date | — |
| Expiry date | Mar 15, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/58
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for homogenizing the static magnetic field with a distribution B0(r) in the active volume of a magnetic resonance apparatus having a number N of shim coils defines a target field distribution B0T(r) using a filter method in which a norm of the shim currents is influenced by means of filter factors. An optimization procedure works in a parameter space having M control parameters, wherein 2≦M<N. One of the control parameters is used as a weighting parameter for modification of a spatial weighting function and another control parameter is used to control the filter factors. Using this method the hardware limitations can be taken into account when determining the target field distribution, without a significant increase in the computational effort to determine the target field distribution during optimization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.