gradient magnetic field

gradient magnetic field

a magnetic field that changes in strength in a given direction. Such fields are used in magnetic resonance imaging (MRI) to select a region for imaging and to encode the location of MRI signals received from the object being imaged.

gradient magnetic field

An MRI term for a small linear magnetic field superimposed on the large static magnetic field during an MRI scan, the strength (amplitude) and direction of which change during the scan such that each small volume element (voxel) within the imaging volume resonates at a different frequency, allowing spatial encoding to be performed.
References in periodicals archive ?
The behavior of dissolved oxygen in gas oil using high gradient magnetic field, Magnetic and Electrical Separation 9(4): 199-211.
For the implementation of a high-quality finishing surface treatment of special optical workpieces magnetorheological polishing method is used [3, 4], which is based on software-controlled tangential material removal by a magnetorheological polishing fluid (MRPF) jet, formed by the gradient magnetic field, with its local contact with the object of the treatment.
Optimization of regime characteristics of the polishing process is based on the control (weight) of material removal from the workpiece surface, which depends on the pressing force of MRPF filler particles, the velocity of their tangential movements, the amount and distribution of them through the gap in the zone of the gradient magnetic field.
The DVMF features a high intensity, high gradient magnetic field generated in the bore of a solenoid coil encased in steel housing.
At gradient magnetic field exposure levels of 50 - 100% above perception threshold, patients may experience pain.
During MR scanning, various acoustic noises are produced, (12) the primary source of which is the gradient magnetic field activation during the MR procedure.
Company's redesigned DVMF features a high intensity, high gradient magnetic field generated in the bore of a solenoid coil encased in steel housing.
At gradient magnetic field exposure levels 50% to 100% above perception threshold, patients may experience pain.
Gradient magnetic fields may stimulate nerves or muscles.
1] Now, manufacturers are introducing MR units that have higher static and gradient magnetic field strengths and are capable of producing a better image in less time.
During imaging, additional small gradient magnetic fields are used to encode this signal with spatial location.
During an MR examination, the patient is exposed to 3 different forms of electromagnetic radiation: radiofrequency (RF), static magnetic field and gradient magnetic fields.