(MEDIC) MEDIC is a heavily T2* weighted spoiled gradient echo sequence with multiple echoes. MEDIC uses a series of identically phase encoded gradient echoes, sampled per line in k-space. Unipolar frequency encoding gradients are used to achieve flow compensation and to avoid off resonance effects. For each echo the magnitude images are reconstructed and postprocessed by using a sum of squares algorithm to improve the signal to noise ratio. The increased receiver bandwidth reduces the T2* effects and impairment of the spatial resolution.
The multi echo data image combination sequence is potentially useful in imaging of cartilage in joints.

Multiple echoes acquired in a gradient echo scan are combined into an image, for less artifacts and higher SNR; the early echoes provide increased SNR, whilst later echoes boost contrast. This sequence type is also known as MERGE (Multiple Echo Recombined Gradient Echo)

See also Multi Echo Data Image Combination, Bipolar Gradient Pulse.

(TGSE / TurboGSE) A sequence with a combination of Gradient and Spin Echo Imaging. Additional gradient echoes are generated before and after each spin echo. The spin echoes are allocated to the center of the raw data matrix to give pure T2 contrast. The gradient echoes primarily determine the image resolution. If multiple image lines are obtained during a single echo, the imaging pulse sequence type is a TGSE pulse sequence. This sequence is very fast, fat is darker and more sensitive to susceptibility effects. Also called GRASE.