Method and apparatus for determining a system frequency in magnetic resonance imaging
AssigneeSiemens Aktiengesellschaft
InventorDaniel Niederloehner
Life of this patent
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Abstract
In a method, device and magnetic resonance (MR) system for determining a system frequency in MR imaging, a frequency spectrum of a region under examination is acquired. A cost function (FOM) is determined that encompasses the difference between a parameterized model function having assigned parameters that is to be optimized, and the acquired frequency spectrum. The cost function is subsequently minimized. Furthermore, the parameters of the optimized parameterized model function assigned to the determined minimum are determined and the system frequency is calculated on the basis of the determined parameters.
Claims14
A method for determining a system frequency for magnetic resonance (MR) imaging, comprising:
- prior to operating an MR data acquisition scanner with a computer in order to acquire diagnostic MR data from an examination region of a subject, providing the computer with a frequency spectrum acquired from the examination region in the MR data acquisition scanner;
- in said computer, automatically determining a cost function that represents a difference between a predetermined model function that is parameterized with assigned parameters, and the acquired frequency spectrum;
- in said computer, executing a minimization algorithm that minimizes said cost function;
- in said computer, executing an optimization algorithm that optimizes said parameterized model function, to obtain an optimized parameterized model function in which at least one of said assigned parameter is changed as a result of said optimization algorithm, and determining parameters of said optimized parameterized model function corresponding to the minimized cost function;
- and
- in said computer, using the determined parameters to set said system frequency and emitting electronic control signals from said computer, that include a designation of said system frequency that has been set, to said MR data acquisition scanner and operating said MR data acquisition scanner at the set system frequency in order to acquire said diagnostic MR data from said examination region.
A magnetic resonance (MR) imaging apparatus comprising:
- an MR data acquisition scanner;
- a control computer configured to operate the MR data acquisition scanner in order to acquire diagnostic MR data from an examination region of a subject, once a system frequency for said MR data acquisition scanner has been set;
- said control computer being configured to operate the MR data acquisition scanner, prior to acquiring said diagnostic data, in order to acquire a frequency spectrum of the examination region;
- said control computer being configured to automatically determine a cost function that represents a difference between a predetermined model function that is parameterized with assigned parameters, and the acquired frequency spectrum;
- said control computer being configured to execute a minimization algorithm that minimizes said cost function;
- said control computer being configured to execute an optimization algorithm that optimizes said parameterized model function, to obtain an optimized parameterized model function in which at least one of said assigned parameter is changed as a result of said optimization algorithm, and determining parameters of said optimized parameterized model function corresponding to the minimized cost function;
- and
- said control computer being configured to use the determined parameters to set said system frequency and to emit electronic control signals from said computer, that include a designation of said system frequency that has been set, to said MR data acquisition scanner and to operate said MR data acquisition scanner at the set system frequency in order to acquire said diagnostic MR data from said examination region.
A non-transitory, computer-readable data storage medium encoded with programming instructions, said storage medium being loaded into a control computer of a magnetic resonance (MR) apparatus, which comprises an MR data acquisition scanner, said programming instructions causing said control computer to:
- prior to operating said MR data acquisition scanner in order to acquire diagnostic MR data from an examination region of a subject, providing the computer with a frequency spectrum acquired from the examination region;
- automatically determine a cost function that represents a difference between a predetermined model function that is parameterized with assigned parameters, and the acquired frequency spectrum;
- execute a minimization algorithm that minimizes said cost function;
- execute an optimization algorithm that optimizes said parameterized model function, to obtain an optimized parameterized model function in which at least one of said assigned parameter is changed as a result of said optimization algorithm, and determine parameters of said optimized parameterized model function corresponding to the minimized cost function;
- and
- use the determined parameters to set said system frequency and emit electronic control signals from said computer, that includes a designation of said system frequency that has been set, to said MR data acquisition scanner, and operate said MR data acquisition scanner at the set system frequency in order to acquire said diagnostic MR data from said examination region.
Dependencies are inferred from the claim text.