longitudinal relaxation


Also found in: Encyclopedia.

lon·gi·tu·di·nal re·lax·a·tion

in nuclear magnetic resonance, the return of the magnetic dipoles of the hydrogen nuclei (magnetization vector) to equilibrium parallel to the magnetic field, after they have been flipped 90°; varies in rate in different tissues, taking up to 15 s for water. See: TI.

longitudinal relaxation

An MRI term for the return of longitudinal magnetisation to equilibrium after excitation due to an exchange of energy between the nuclear spins and the lattice.

lon·gi·tu·di·nal re·lax·a·tion

(long'ji-tū'di-năl rē'lak-sā'shŭn)
magnetic resonance imaging The return of the magnetic dipoles of the hydrogen nuclei (magnetization vector) to equilibrium parallel to the magnetic field, after they have been flipped 90°; varies in rate in different tissues, taking up to 15 seconds for water.
See: TI
References in periodicals archive ?
For both transverse and longitudinal relaxation weighting, the separation in two phases is clearly visible.
No contrast inversion is observed during this period as the longitudinal relaxation is insensitive to diffusion.
The intensity is enhanced with respect to the remaining lower phase because of the more rapid longitudinal relaxation.

Full browser ?