Magnetic resonance imaging apparatus and control method thereof
AssigneeFUJIFILM Corporation
InventorsKazuho Kamba, Masahiro Takizawa, Taisei Ueda, Nobuyuki Yoshizawa, Atsushi Kuratani, Kosuke Ito
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Abstract
Preventing blood flow artifacts from being increased in an imaging plane allows reduction of the blood flow artifacts in the cross section subsequently excited. In the imaging using a spin-echo (SE) pulse sequence, an excitation width of a 90° pulse is extended from an imaging plane to one side. This one side indicates a downstream side of the blood flow with respect to a vessel of interest. In imaging multiple slices, the order of measuring the multiple imaging slices is set along the direction in which the width is extended.
Claims11
A magnetic resonance imaging apparatus comprising,
- a measurement unit configured to apply an RF pulse to excite a predetermined cross section of an examination subject and gradient magnetic field pulses, and to collect nuclear magnetic resonance signals generated from the predetermined cross section, and
- a measurement control unit configured to control the measurement unit so that the measurement unit collects the nuclear magnetic resonance signals according to a spin-echo pulse sequence, and to control at least either of an excitation pulse and the gradient magnetic field pulse included in the spin-echo pulse sequence in such a manner that a width in a thickness direction of the predetermined cross section excited by the excitation pulse in the spin-echo pulse sequence is extended from an imaging plane of the predetermined cross section only to a downstream side of a liquid that flows into the predetermined cross section, so that the width includes the predetermined cross section and a region adjacent to the predetermined cross section on the downstream side, and the width, after being extended, does not include any region adjacent to the predetermined cross section to an upstream side of the liquid that flows into the predetermined cross section.
A control method of a magnetic resonance imaging apparatus provided with an RF magnetic field generation unit configured to generate an RF magnetic field to be applied to the examination subject, a gradient magnetic field generation unit configured to generate a gradient magnetic field in a space in which the examination subject is placed, and a measurement unit configured to measure a nuclear magnetic resonance signal generated from the examination subject, the magnetic resonance imaging apparatus being operated according to a predetermined pulse sequence, and the control method comprising:
- using as the pulse sequence, a spin-echo pulse sequence that includes application of a 90° pulse and application of a 180° pulse and measures a spin echo from a predetermined cross section of the examination subject;
- controlling one or more of an excitation pulse and the gradient magnetic field pulse included in the spin-echo pulse sequence in such a manner that a width in a thickness direction of the predetermined cross section excited by the excitation pulse in the spin-echo pulse sequence is extended from an imaging plane of the predetermined cross section only to a downstream side of a liquid that flows into the predetermined cross section, so that the width includes the predetermined cross section and a region adjacent to the predetermined cross section on the downstream side, and the width, after being extended, does not include any other region adjacent to the predetermined cross section to an upstream side of the liquid that flows into the predetermined cross section;
- and
- collecting the nuclear magnetic resonance signals from the predetermined cross section, with setting a range excited by the 90° pulse as a range that includes the predetermined cross section and the region adjacent to the predetermined cross section and located on the downstream side of a fluid flowing into the predetermined cross section, and setting a range to apply the 180° pulse to coincide with the range of the predetermined cross section.
Dependencies are inferred from the claim text.