pulse sequence


Also found in: Dictionary, Thesaurus, Encyclopedia.

pulse sequence

in magnetic resonance imaging, a series of changes in the induced magnetic field, which include the phase and frequency-encoding gradients and read-out functions.

pulse sequence

An MRI term for a preselected set of defined radio frequency and gradient pulses, which are repeated multiple times during a scan, through which the time intervals between pulses and the amplitude and shape of the gradient waveforms control NMR signal reception and affect the characteristics of the resulting images.

pulse se·quence

(pŭls sē'kwĕns)
magnetic resonance imaging A series of changes in the induced magnetic field, which includes the phase and frequency-encoding gradients and read-out functions.
References in periodicals archive ?
Dependence of radiomic features on pulse sequence parameters (i.e., TR and TE) was assessed for T1-weighted spin-echo imaging.
used iron oxide contrast agent in the pulse sequence spin echo (SE) and GE.
This study used a 3T magnet combined with a custom-made surface coil and a pCASL pulse sequence. Using this ASL setup and measuring four young healthy volunteers, it was found that, compared to the resting state (60 [+ or -] 5 beats per minute and arterial pressure of 78 [+ or -] 5 mmHg), the retinal blood perfusion increased by 25% [+ or -] 7% and ocular perfusion pressure increased by 25% [+ or -] 6% in the exercise mode.
Martinez-Moller and core-searchers reported a technique including a sorting method of attenuation map for the four parts (background, lungs, fat, and soft tissue), on the basis of 2-point Dixon MRI pulse sequence. However, there is a known weak point in their method, which is that it neglects latent effects of cortical bone [6].
Indeed, starting from the optimized pulse sequence achieved in the preliminary example, described by the parameters [[??].sup.R.sub.nq] and [[??].sup.F.sub.nq] (n = 1, ...
The strategy considered here to overcome the problem of a large J value, which is a particular source of the sidebands, was to combine CW decoupling with other decoupling pulse sequences by applying both simultaneously.
These factors most often relate to hardware (eg, magnetic field strength and surface coil technology), software (eg, pulse sequence selection, image manipulation and postprocessing), technologist performance (eg, correct patient positioning, proper instructions and precise contrast administration), patient cooperation and metal implants within the patient.
For a faster pulse sequence 0.45/0.8 (the Mulvany DCVG pulse) the difference between ON and OFF readings is 0.3 to 0.5 meters.
Subjects underwent two phases of data collection: 1) MRI assessment of the knee, patellofemoral joint, and thigh using a T1-weighted, fast spin echo pulse sequence (1.5T MR system) and 2) standard gait analysis (kine matics, kinetics and EMG) during a self selected walking speed.
The software written to control these channels is called a pulse sequence. The timing parameters inside the pulse sequence can be adjusted to produce various types of tissue contrast.
Signal strength, in turn, depends on (1) the timing of the excitation-refocusing pulses, called the "pulse sequence" and (2) certain intrinsic physical properties of the tissue.
The J-resolved pulse sequence was used to identify unusual peaks.