# US 2014/0152305 A1 · Magnetic resonance imaging method and apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0152305 A1 - Document ID: US20140152305A1 - Status: Published application - Kind: A1 - Application number: 14/074,038 - Filed: 2013-11-07 - Published: 2014-06-05 - Earliest claimed: 2012-12-05 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Jong-bum SON; Seong-deok LEE; Jaemock YI - Web page: https://patentgrep.com/patent/US20140152305A1 ## CPC - G01R 33/56563: {caused by a distortion of the main magnetic field B0, e.g. temporal variation of the magnitude or spatial inhomogeneity of B0 (G01R33/56509, G01R33/56518, G01R33/56536 take precedence)} - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract A magnetic resonance imaging (MRI) method and apparatus are provided including a signal acquirer, a resonance frequency acquirer, and an RF driver. The signal acquirer is configured to acquire a free induction decay (FID) signal or an echo signal to generate a magnetic resonance image of a portion of an area of a subject. The resonance frequency acquirer is configured to acquire a resonance frequency of the portion of the area from the acquired FID signal. The RF driver is configured to generate a refocusing RF pulse having the acquired resonance frequency. The signal acquirer, the resonance frequency acquirer and the RF driver are configured to acquire and generate in each of sections of an RF pulse sequence. ## Claims ### Claim 1 A magnetic resonance imaging (MRI) method, comprising: acquiring a resonance frequency of a portion of an area of a subject from a free induction decay (FID) signal; and applying a refocusing radio frequency (RF) pulse comprising the resonance frequency to acquire an echo signal to generate a magnetic resonance image of the portion of the area, wherein the acquiring of the resonance frequency and the applying of the refocusing RF pulse are performed in each of sections of an RF pulse sequence. ### Claim 2 (depends on 1) The MRI method as recited in claim 1, further comprising: applying an excitation RF pulse to acquire the FID signal, wherein the excitation RF pulse of a next section of each of the sections has the resonance frequency acquired in each of the sections of the RF pulse sequence. ### Claim 3 (depends on 1) The MRI method as recited in claim 1, wherein two refocusing RF pulses of each of the sections of the RF pulse sequence have the resonance frequency acquired in each of the sections of the RF pulse sequence. ### Claim 4 (depends on 1) The MRI method as recited in claim 1, wherein the acquiring of the resonance frequency is performed in real-time. ### Claim 5 (depends on 1) The MRI method as recited in claim 1, wherein the acquiring of the resonance frequency comprises: acquiring the FID signal of the portion of the area in response to an applied excitation RF pulse, performing Fourier Transform of the acquired FID signal, determining a frequency having a peak value from a frequency spectrum of the acquired FID signal according to the Fourier Transform, and acquiring the determined frequency having the peak value as the resonance frequency of the portion of the area. ### Claim 6 (depends on 1) The MRI method as recited in claim 1, further comprising: configuring the RF pulse sequence to be a spin echo or a fast spin echo. ### Claim 7 (depends on 1) The MRI method as recited in claim 1, further comprising: configuring an excitation RF pulse to acquire the FID signal to be a 90° RF pulse, and the refocusing RF pulse to be 180° RF pulse. ### Claim 8 (depends on 1) The MRI method as recited in claim 1, further comprising: configuring the predetermined area to be a 2-dimensional (2D) cross-section of the subject or a 3-dimensional (3D) sub-volume. ### Claim 9 (depends on 1) A computer program embodied on a non-transitory computer readable medium, the computer program being configured to control a processor to perform the MRI method of claim 1. ### Claim 10 A magnetic resonance imaging (MRI) apparatus, comprising: a signal acquirer configured to acquire a free induction decay (FID) signal or an echo signal to generate a magnetic resonance image of a portion of an area of a subject; a resonance frequency acquirer configured to acquire a resonance frequency of the portion of the area from the acquired FID signal; and an RF driver configured to generate a refocusing RF pulse having the acquired resonance frequency, wherein the signal acquirer, the resonance frequency acquirer and the RF driver are configured to acquire and generate in each of sections of an RF pulse sequence. ### Claim 11 (depends on 10) The MRI apparatus as recited in claim 10, wherein the RF driver uses the acquired resonance frequency to generate an excitation RF pulse of a next section of each of the sections. ### Claim 12 (depends on 10) The MRI apparatus as recited in claim 10, wherein the RF driver uses the resonance frequency acquired in each of the sections to generate at least two refocusing RF pulses of each of the sections. ### Claim 13 (depends on 10) The MRI apparatus as recited in claim 10, wherein the resonance frequency acquirer acquires the resonance frequency in real-time. ### Claim 14 (depends on 10) The MRI apparatus as recited in claim 10, wherein the resonance frequency acquirer comprises: a converter configured to perform Fourier Transform of the acquired FID signal, a determiner configured to determine a frequency having a peak value from a frequency spectrum of the acquired FID signal according to the Fourier Transform to acquire the resonance frequency of the portion of the area, and a storage configured to store the acquired FID signal and the acquired resonance frequency. ### Claim 15 (depends on 10) The MRI apparatus as recited in claim 10, wherein the RF pulse sequence is a spin echo or a fast spin echo. ### Claim 16 (depends on 10) The MRI apparatus as recited in claim 10, wherein an excitation RF pulse to acquire the FID signal is a 90° RF pulse, and the refocusing RF pulse is 180° RF pulse. ### Claim 17 (depends on 10) The MRI apparatus as recited in claim 10, wherein the predetermined area is a 2D cross-section of the subject or a 3D sub volume.