NMR static and rotating frame relaxation studies in solid Cl3CC(CH3)2Cl

1973 ◽  
Vol 59 (3) ◽  
pp. 1069-1076 ◽  
Author(s):  
Shmuel Albert ◽  
John A. Ripmeester
Author(s):  
Maximilian Gram ◽  
Michael Seethaler ◽  
Daniel Gensler ◽  
Johannes Oberberger ◽  
Peter M. Jakob ◽  
...  

1999 ◽  
Vol 140 (1) ◽  
pp. 250-258 ◽  
Author(s):  
F. Guenneau ◽  
P. Mutzenhardt ◽  
D. Grandclaude ◽  
D. Canet

2011 ◽  
Vol 24 (7) ◽  
pp. 807-814 ◽  
Author(s):  
Silvia Mangia ◽  
Timo Liimatainen ◽  
Michael Garwood ◽  
Ivan Tkac ◽  
Pierre-Gilles Henry ◽  
...  

2008 ◽  
Vol 29 (1) ◽  
pp. 206-216 ◽  
Author(s):  
Kimmo T Jokivarsi ◽  
Juha-Pekka Niskanen ◽  
Shalom Michaeli ◽  
Heidi I Gröhn ◽  
Michael Garwood ◽  
...  

The rotating frame longitudinal relaxation magnetic resonance imaging (MRI) contrast, T1ρ, obtained with on-resonance continuous wave (CW) spin-lock field is a sensitive indicator of tissue changes associated with hyperacute stroke. Here, the rotating frame relaxation concept was extended by acquiring both T1ρ and transverse rotating frame ( T2ρ) MRI data using both CW and adiabatic hyperbolic secant (HSn; n = 1, 4, or 8) pulses in a rat stroke model of middle cerebral artery occlusion. The results show differences in the sensitivity of spinlock T1ρ and T2ρ MRI to detect hyperacute ischemia. The most sensitive techniques were CW- T1ρ and T1ρ using HS4 or HS8 pulses. Fitting a two-pool exchange model to the T1ρ and T2ρ MRI data acquired from the infarcting brain indicated time-dependent increase in free water fraction, decrease in the correlation time of water fraction associated with macromolecules, and increase in the exchange correlation time. These findings are consistent with known pathology in acute stroke, including vasogenic edema, destructive processes, and tissue acidification. Our results show that the sensitivity of the spinlock MRI contrast in vivo can be modified using different spinlock preparation blocks, and that physicochemical models of the rotating frame relaxation may provide insight into progression of ischemia in vivo.


Sign in / Sign up

Export Citation Format

Share Document