Magnetic resonance imaging apparatus and method for controlling the velocity of venuous and arterial blood

A magnetic resonance imaging apparatus configured to image a subject such that arterial blood of the subject is emphasized over a venous blood flowing at a velocity slower than the arterial blood, the magnetic resonance imaging apparatus comprising:

• a transmission coil configured to transmit can RF pulse to the subject;
• a gradient coil configured to apply a gradient pulse to the subject;
• and
• a coil control device configured to control the transmission coil and the gradient coil such that:
• a longitudinal magnetization reversal pulse is transmitted to reverse longitudinal magnetization components positive in value of the arterial blood and the venous blood such that the arterial blood and the venous blood respectively have longitudinal magnetization components negative in value;
• after the transmission of the longitudinal magnetization reverse pulse, a longitudinal magnetization adjustment pulse sequence is executed in order to set the longitudinal magnetization component of the arterial blood larger than the longitudinal magnetization component of the venous blood, the longitudinal magnetization adjustment pulse sequence comprising:
• a first RF pulse configured to rotate the longitudinal magnetization components of the arterial blood and the venous blood by an angle of 45°;
• and
• a second RF pulse configured to rotate the longitudinal magnetization components of the arterial blood and the venous blood by an angle of −45°;
• and
• after the transmission of the longitudinal magnetization reverse pulse, a data acquisition pulse sequence is executed in order to acquire data related to the arterial blood when an absolute value of the longitudinal magnetization component of the arterial blood flowing through an imaging area is larger than an absolute value of the longitudinal magnetization component of the venous blood.

A method for controlling a magnetic resonance imaging apparatus which images a subject in such a manner that arterial blood of the subject is emphasized over venous blood flowing at a velocity slower than the arterial blood, the method comprising:

• executing a longitudinal magnetization adjustment pulse sequence in order to set a longitudinal magnetization component positive in value for the arterial blood that is smaller than a longitudinal magnetization component positive in value of the venous blood with respect to the arterial blood and the venous blood, wherein the longitudinal magnetization adjustment pulse sequence includes:
• a first RF pulse configured to rotate the longitudinal magnetization components of the arterial blood and the venous blood by an angle of 45°;
• and
• a second RF pulse configured to rotate the longitudinal magnetization components of the arterial blood and the venous blood by an angle of −45°;
• after the execution of the longitudinal magnetization adjustment pulse sequence, transmitting a longitudinal magnetization reverse pulse in order to reverse the longitudinal magnetization components of the arterial blood and the venous blood;
• and
• after the transmission of the longitudinal magnetization reverse pulse, executing a data acquisition pulse sequence in order to acquire data related to the arterial blood when can absolute value of the longitudinal magnetization component of the arterial blood flowing through an imaging area is larger than an absolute value of the longitudinal magnetization component of the venous blood.