transverse relaxation

trans·verse re·lax·a·tion

in nuclear magnetic resonance, the decay of the nuclear magnetization vector at right angles to the magnetic field after the 90° pulse is turned off; the signal is called free induction decay. See: T2. Compare: longitudinal relaxation.
Farlex Partner Medical Dictionary © Farlex 2012

trans·verse re·lax·a·tion

(trans-vĕrs' rē'lak-sā'shŭn)
magnetic resonance imaging The rapid decay of the nuclear magnetization vector at right angles to the magnetic field after the 90° pulse is turned off; the signal is called free induction decay.
See also: T2
Compare: longitudinal relaxation
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
A decrease of 169 ms is observed for longitudinal relaxation time [T.sub.1] and of 161 ms for transverse relaxation time [T.sub.2] (see values of relaxation times at maximum in Table 4).
The previous studies about skeletal muscle have reported that the cause for variety of relaxation time included muscle fiber composition, intracellular and extracellular water content, perfusion, lipids, and other conditions in the case of the same external environment, especially the present of water and fat of tissue.[10],[11],[12] Moreover, bound water which was associated with intracellular protein, glycogen, and other macromolecules slowed down the resonance frequency closer to the Larmor frequency, causing more efficient longitudinal and transverse relaxation, thereby shortening both T1 and T2 relaxation times of water.
Further analysis of the 24-week interim dataset showed a statistically significant decrease in muscle inflammation as measured by magnetic resonance spectroscopy transverse relaxation time T2.
The association of the transverse relaxation time, [T.sub.2], and the solid-liquid separation characteristics in the leaching process, as well as the specific surface area of pores, is more evident, which reflects the change in the characteristics of the pore structures in rare earth samples in the leaching process to a certain extent.
Low-field NMR is used to test coal by low magnetic field intensity and detect the nuclear magnetic signal of [sup.1]H in water-saturated coal rock pores to gain the transverse relaxation time ([T.sub.2]) spectrum of [sup.1]H and the [T.sub.2] spectrum of water in water-saturated coal rock.
The longitudinal relaxation time (T1, ms) and transverse relaxation time (T2, ms) of the synthesized PEG contrast agent solutions were measured using a 300 MHz (7.1 T) NMR spectrometer with a combination of measurements obtained in a large NMR tube (650 [micro]L of deuterium oxide to dilute the synthesized PEG contrast agents to different concentrations from 0.05 mM to 0.8 mM) and in a small tube (containing 50 [micro]L of benzene-D6).
Prammer [52] presented the relation between the amplitude attenuation of NMR and the transverse relaxation time ([T.sub.2]) and pointed out that the fluid viscosity is correlated positively with the attenuation rate of fluid amplitude.
Two transverse relaxation time constants, [T.sub.21] and [T.sub.22], are spin-spin relaxation time constants and were identified from the NMR experiments using the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence.
There are two types of NMR relaxations which generate magnetic resonance images: longitudinal relaxation ([T.sub.1] recovery) and transverse relaxation ([T.sub.2] decay).
Iron ions that accumulate in tissue can cause local distortion in the relaxation of spins and the body's magnetic field due to their superparamagnetic features and thus cause T1 (longitudinal relaxation time), T2 (transverse relaxation time), and, especially, T2 star (T2*) (transverse relaxation time affected by magnetic field in homogeneity) shortening.
The obtained difference in the electronic transverse relaxation [T.sub.2e] can indicate the higher local concentration of [Mn.sup.2+] ions in the unstable plaques, that is, the more homogeneous distribution of [Mn.sup.2+] ions in stable plaques.

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