(TGA) Therapeutic Goods Administration is Australia's regulatory agency for medical drugs and devices. The TGA is a unit of the Australian Government Department of Health and Ageing. The Australian Drug Evaluation Committee (ADEC) controls the approval and registration of, for example contrast media (contrast agents).

A state in which all parts of a system are at the same effective temperature, in particular where the relative alignment of the spins with the magnetic field is determined solely by the thermal energy of the system (in which case the relative numbers of spins with different alignments will be given by the Boltzmann distribution).

(TONE) Used to decrease the saturation effect of inflowing blood in 3D MRA scans, the flip angle varies linearly over the excited chunk. In multi chunk scans TONE decreases the Venetian blind artifact or allows thicker chunks to cover a larger anatomical region.

See also Variable Flip Angle.

(TD) The difference in time between radio frequency spin echo (TER) and gradient echo (TE) when the RF and gradient echoes are not coincident.

(TE) Time between middle of exciting (e.g., 90°) RF pulse and middle of spin echo production. For multiple echoes, use TE1, TE2, etc. When the RF spin echo and gradient echo are not coincident in time, TE refers to the time of the gradient spin echo. See also Echo Time.