MRS chemical shift difference between protons, using the information gained about their environment in a microscopic imaging technique protons. The negatively charged ions move around the protons on protons "shielding" (shading) information is available to replace partially the effect of magnet on the proton. Water and protons in different chemical relationships in the adipose tissue is in the oscillation frequency (chemical shift) will be different. This chemical shift can be defined and the amount of metabolites can be determined by the difference in tissue examined.
Single-voxel spectroscopy method is used in spectroscopy studies of the liver, and single-shot techniques review "Point Resolved
Spectroscopy "(PRESS), or" Stimulated Echo Acquisition Mode "(STEAM) and can be realized. STEAM'da 90 ° -90 ° -90 ° pulse sequence used, PRESS'te longer "time of the echo" (TE) and 90 ° -180 ° -180 ° pulse sequence is used. PRESS technique, a higher "signal-noise ratio," or (SNR) is a metabolite is more suitable for quantification. However, the determination of metabolites in fat and high SNR'ye Press, quantification is not needed because it is more sensitive to defects in STEAM spectroscopy of liver come forward. Voxel placed in the area to be examined does not contain the main arteries and abdominal fat tissue to avoid exposure, it is important that the abdominal wall 10 mm from the inner border