Aims and objectives
Magnetization transfer (MT) is a cross relaxation phenomenon in which the proton is able to move freely; known as bulk water and bound water.
The MT effect is observed and provides the signal attenuation for the MT pulse; then,
a RF pulse is added at an off-resonance frequency.
This method is said to be the off-resonance method.
Signal attenuation occurred for MT pulse by interaction between bulk water and bound water e.g.,
spin exchange,
and chemical shift.
The magnetization transfer contrast (MTC) method is demonstrated...
Methods and materials
We performed a phantom experiment.
The phantom was created using a set of six samples in a cylindrical vessel.
The sample components used were deionized water with polyethylene glycol (PEG) macromolecules at different concentrations (0,
10,
20,
30,
40,
and 50 wt%).
Figure 1 shows the schematics of the phantom used in this study.
All imaging analysis were applied using an in-house program,
MATLAB (Mathworks,
Natick,
MA,
USA).
A chart of the procedure of this study is shown in Fig.
2.
1.
MR imaging
On...
Results
Table 3 shows the relationship between PEG concentrations and mean T1 values of each sample with and without a MT pulse.
Figure 7 shows T1 map derived from the VFA method with and without a MT pulse (Off-set frequency: 800,
1600 Hz).
Figure 8 shows a graph of the data,
Table.
3.
By the addition of MT pulse,
the change in T1 values was seen,
but there were almost no changes caused by differences in offset frequency of the MT pulse.
In the PEG 30%...
Conclusion
Determination of T1 with a MT pulse makes it possible to obtain more detailed information of macromolecules not provided when using MTR.
Personal information
Author Names:
Toshiaki Sasaki1,Yuki Kanazawa2,Yuki Matsumoto1,Hiroaki Hayashi2,
Natsuki Ikemitsu1,
Takatoshi Usuda1,
Mitsuharu Miyoshi3,
and Masafumi Harada2
Author Affiliations:
1.
School of Health Sciences,
Tokushima University
2.
Institute of Biomedical Sciences,
Tokushima University Graduate School
3.
MR Applications and Workflow Asia Pacific GE Healthcare Japan Corporation
Corresponding Author and Reprint Info:
Yuki Kanazawa,
PhD
Institute of Biomedical Sciences,
Tokushima University Graduate School
3-18-15,
Kuramoto-Cho,
Toksuhima City,
Tokushima,
770-8509,
Japan
E-mail:
[email protected]
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