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The generated transverse magnetization can then induce a signal in an RF coil that can be detected and amplified by an RF receiver. The return of the longitudinal component of the magnetization to its equilibrium value is termed spin-lattice relaxation while the loss of phase-coherence of the spins is termed spin-spin relaxation, which is ...
T 2 relaxation curve Visualization of the and relaxation times.. In physics, the spin–spin relaxation is the mechanism by which M xy, the transverse component of the magnetization vector, exponentially decays towards its equilibrium value in nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI).
The third part of the pulse sequence, another slice selection (of the same slice) uses another shaped pulse to cause a 180° rotation of transverse nuclear magnetization within the slice. This transverse magnetisation refocuses to form a spin echo at a time T E. During the spin echo, a frequency-encoding (FE) or readout gradient is applied ...
T 1ρ MRI is an alternative to conventional T 1 and T 2 MRI by its use of a long-duration, low-power radio frequency referred to as spin-lock (SL) pulse applied to the magnetization in the transverse plane. The magnetization is effectively spin-locked around an effective B 1 field created by the vector sum of the applied B 1 and any off ...
The longitudinal magnetization, M z remains constant in time. This is also how the transverse magnetization appears to an observer in the laboratory frame of reference (that is to a stationary observer). M xy (t) is translated in the following way into observable quantities of M x (t) and M y (t): Since
Bulk water molecules are also relatively far from magnetic field perturbing macromolecules, such that free water protons experience a more homogeneous magnetic field, which results in slower transverse magnetization dephasing and a longer T 2 *. Conversely, hydration water molecules are mechanically constrained by extensive interactions with ...
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields , magnetic field gradients, and radio waves to form images of the organs in the body.
T 2 *-weighted imaging is built from the basic physics of magnetic resonance imaging where there is spin–spin relaxation, that is, the transverse component of the magnetization vector exponentially decays towards its equilibrium value.