Pulse sequences, designed to be insensitive to flow, e.g. at every even echo, a spin echo sequence is not flow sensitive. Velocity compensation is achieved by using gradients, which are either symmetrical around a 180° pulse and switched on twice as is the case for motion compensated spin echo pulse sequences, or two antisymmetrical gradient lobes without 180° pulse, which is the way to produce a velocity compensated gradient echo pulse sequence.
The signal of the second echo (and all other even echoes) is independent of the velocity of the object. Thus, velocity-based motion effects stemming from the entire voxel or from spins within a voxel (intravoxel incoherent motion) are suppressed with such pulse sequences.
If higher order motion is relevant, as it may be in turbulent jets across valves, acceleration and jerk effects can also be compensated for by the use of appropriate combinations of gradient- and radio frequency pulses.
With the increasingly stronger gradients, echo times in MR systems can be shortened to the point at which effects other than velocity effects hardly ever become relevant.

The phase shift is the loss of phase coherence in precessing spins. Vascular spins move at variable velocities; faster flow undergo a stronger phase shift than slower flowing spins.

(RIS) Radiology information system means a computer system that stores and processes the information for a radiology department and can be linked to the hospital information system.
The principal purpose of a RIS consists of taking over the general functions of the administration inclusive planning, monitoring and communication of all data regarding patients and its investigations in the radiology. The correct images should reach, at the correct time, the correct users. For this reason the RIS must contain a workflow management in order to simplify and steer the data flow at the individual view stations or devices (laser cameras etc.). The Radiology Information System is optimally complemented with a Picture Archiving and Communication System (PACS).

T2 weighted imaging relies upon local dephasing of spins following the application of the transverse energy pulse. The contrast of a T2 weighted image is predominantly dependent on T2 and the T2 dependence will be increased by using a long echo time.
Fat has a shorter T2 time than water and relaxes or decays more readily than water. Since the amount of transverse magnetization in fat is small, fat generates very little signal on a strong T2 weighted contrast image and appears intermediate to dark. The T2 weighting is stronger with a longer TE. Water has a very high T2 constant, therefore has very high T2 signal and thus appears bright on a T2 contrast image. Cerebral white matter (fat containing) is less intense than grey matter. Flowing blood (flow effects) and haematomas (haemoglobin, haemosiderin) have a variable signal intensity on MR images.
Images created with TR's and TE's to enhance T2 contrast are referred to as T2 weighted images. Both T1 and T2 weighted images are acquired for most medical MRI examinations.

(VENC) A specialized technique used for encoding flow-velocities.
The velocity encoding value is given by:
VENC = pi / gamma DELTA M1.
Gamma is the gyromagnetic ratio, and DELTA M1 is the gradient moment and is proportional to the area of the flow encoding gradient waveform.

See also Phase Contrast Sequence, Phase Contrast Angiography, and Bipolar Gradient Pulse.