Relaxation (NMR) - Common Relaxation Time Constants in Human Tissues

Common Relaxation Time Constants in Human Tissues

Following is a table of the approximate values of the two relaxation time constants for nonpathological human tissues, just for simple reference.


At a main field of 1.5 T
Tissue Type Approximate T1 value in ms Approximate T2 value in ms
Adipose tissues 240-250 60-80
Whole blood (deoxygenated) 1350 50
Whole blood (oxygenated) 1350 200
Cerebrospinal fluid (similar to pure water) 4200 - 4500 2100-2300
Gray matter of cerebrum 920 100
White matter of cerebrum 780 90
Liver 490 40
Kidneys 650 60-75
Muscles 860-900 50

Following is a table of the approximate values of the two relaxation time constants for chemicals that commonly show up in human brain magnetic resonance spectroscopy (MRS) studies, physiologically or pathologically.


At a main field of 1.5 T
Signals of Chemical Groups Relative resonance frequency Approximate T1 value (ms) Approximate T2 value (ms)
Creatine (Cr) and Phosphocreatine (PCr) 3.0 ppm gray matter: 1150-1340,
white matter: 1050-1360		 gray matter: 198-207,
white matter: 194-218
N-Acetyl group (NA),
mainly from N-Acetylaspartate (NAA)		 2.0 ppm gray matter: 1170-1370,
white matter: 1220-1410		 gray matter: 388-426,
white matter: 436-519
—CH3 group of
Lactate		 1.33 ppm
(doublet: 1.27 & 1.39 ppm)		 (To be listed) 1040

Read more about this topic:  Relaxation (NMR)

Famous quotes containing the words common, relaxation, time and/or human:

    “Nothing is more repugnant to me than brotherly feelings grounded in the common baseness people see in one another.”
    —Milan Kundera (b. 1929)

    “Worst of all, there is no sign of any relaxation of antisemitism. Logically it has nothing to do with Fascism. But the human race is imitative rather than logical; and as Fascism spreads antisemitism spreads.”
    —George Bernard Shaw (1856–1950)

    “There may be always a time of innocence.
    There is never a place.”
    —Wallace Stevens (1879–1955)

    “If we find the answer to that, it would be the ultimate triumph of human reason—for then we would know the mind of God.”
    —Stephen Hawking (b. 1942)