For both phantom protocols, conventional low-resolution 2D GRE scans were acquired as sensitivity reference scans for parallel imaging reconstruction of separate fat and water images. 3.2.2 In vivo measurements Separation/suppression and image quality The human body contains essential fat, which is distributed over the whole body and is crucial for its function, and subcutaneous and visceral fat, which serve as energy reserves. The fat signal comprises many spectral components, but because about 80% of the total signal stems from peaks with shifts between 3.2 and 3.9ppm from water, 1 it is often considered, for practical purposes, as having only a single peak with a 3.5ppm shift relative to water. 2 Visualization of fatty tissues provides valuable insights into physiology and pathology, but the chemical shift of fat with respect to water gives rise to artifacts. First, it leads to a displacement of the fat image relative to the water image along all frequency-encoding directions (Type1 chemical shift artifact). Second, in gradient echo (GRE) imaging, interference between the fat and water signals, which are subject to different phase evolutions, leads to complex signal cancellation when acquired at any time other than in-phase echo times (TEs) (Type2 chemical shift artifact). Moreover, the shorter T 1 and longer T 2 relaxation times of fat lead it to appear hyperintense, obscuring the water signal of primary interest.

Cha JG, Jin W, Lee MH, Kim DH, Park JS, Shin WH, et al. Reducing metallic artifacts in postoperative spinal imaging: usefulness of IDEAL contrast-enhanced T1- and T2-weighted MR imaging--phantom and clinical studies. Radiology. 2011;259(3):885–93. and, indeed, different protons within a molecule) resonate at different frequencies in the presence of a magnetic field. This is the basis of NMR spectroscopy Popkin BM, D'Anci KE, Rosenberg IH. Water, hydration, and health. Nutr Rev. 2010;68(8):439-4358. doi:10.1111/j.1753-4887.2010.00304.x

Saturated fat guidelines

Chumlea WC, et al. (1999). Total body water data for white adults 18 to 64 years of ages: The Fels Longitudinal Study. DOI: Meyer CH, Pauly JM, Macovski A, Nishimura DG. Simultaneous spatial and spectral selective excitation. Magn Reson Med. 1990; 15: 287- 304. Remember that in MRI, one part of localizing signal to a particular voxel (point in space) is by using frequency encoding. We set up an magnetic field gradient

Chemical shift artifact of the second kind does not occur in spin echo sequences. This is because the 180-degree pulse 'rewinds' the phase shifts: FIGURE S2 (with Table S1) Comparison of SNR and SNR efficiency between 2D GRE a) SMURF, b) three-point Dixon with long TR (same as SMURF) c) three-point Dixon with short TR, assessed on the separated water and fat images. The shown SNR and SNR efficiency values represent the median of the values in all ROIs localized in the same areas and over the four repetitions. The SNR and SNR efficiency of SMURF is decreased compared to the Dixon approach – note the highest relative decrease in the liver Excitation selectivity and unaliasing quality of Simultaneous Multiple Resonance Frequency imaging (SMURF) demonstrated for one exemplary volunteer for each body region under consideration. The acquired aliased images show the overlapping water and CAIPIRINHA-shifted (along the phase-encoding (PE) direction) fat images. Separate SMURF water and fat images, reconstructed from the aliased images, illustrate the achieved separation quality. (The separated images were rescaled for improved visibility.) For example, if the BW = 32 kHz and the matrix size is 256, then Δf / pixel, also referred to as BW/pixel, is 125 Hz. Now, as shown above, Xiang QS, An L. Water-fat imaging with direct phase encoding. J Magn Reson Imaging. 1997; 7: 1002- 1015.

in the MR image formation parameters section). Note that since this phenomenon is caused by frequency shifts, it applies to the frequency-encoding direction only. Reeder SB, Pineda AR, Wen Z, Shimakawa A, Yu H, Brittain JH, et al. Iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL): application with fast spin-echo imaging. Magn Reson Med. 2005;54(3):636–44. The best drinks to give children are water and milk. Children should drink whole milk until they're 2 years old. Adan A. Cognitive performance and dehydration. J Am Coll Nutr. 2012;31(2):71-8. doi:10.1080/07315724.2012.10720011 Now, in principle that means we can use TE out-of-phase = 1.1 ms. However, it turns out that this is too short for the gradients and MR electronics

FIGURE S5 Comparison gradient echo water and fat images of the abdomen obtained using fat-saturation and water-saturation (top row), two-point Dixon (second row), three-point Dixon (third row) and SMURF (bottom row) for the two volunteers not shown in the main manuscript (Figure 8). Fat-saturated images show quite high residual signal and lower image SNR. Two-point Dixon water images show high residual fat signal and artefacts at the edges of some tissue boundaries (gold arrows), but no fat-water swaps. Three-point Dixon images show clear fat-water separation (very little residual signal), but several fat-water swaps (blue arrows). SMURF images show very little residual signal and no fat-water swaps. (Note that FatSat/WaterSat, three-point Dixon and SMURF images were acquired using 2D imaging, while two-point Dixon images were acquired using slab-selective 3D imaging approach. The same non-linear grey scales were used for all fat images and all water images.) Medical News Today has strict sourcing guidelines and draws only from peer-reviewed studies, academic research institutions, and medical journals and associations. We avoid using tertiary references. We link primary sources — including studies, scientific references, and statistics — within each article and also list them in the resources section at the bottom of our articles. You can learn more about how we ensure our content is accurate and current by reading our editorial policy. Simon JH, Szumowski J. Proton (fat/water) chemical shift imaging in medical magnetic resonance imaging. Current status. Invest Radiol. 1992; 27: 865- 874. Your body naturally tries to maintain healthy water levels by excreting excess water in urine. The more water and fluids you drink, the more urine is produced in the kidneys. Knowing your body composition gives you a complete picture of your body health and provides insights into areas you need to focus on.SMURF can be combined with both partial Fourier and parallel imaging acceleration to reduce the acquisition time. As in SMS imaging, the maximum acceptable acceleration factor will generally be reduced compared to that which can be used in conventional (broadband excitation) imaging, as SMURF takes advantage of the spatially varying coil sensitives to separate fat and water. SMURF does not pose any special requirements on the reference data needed for fat-water separation; the reference data commonly acquired in accelerated imaging (ie, a set of fully sampled central k-space lines, “auto-calibration scan” 27) could be used. Remember, with excess weight comes an increased risk of heart disease, stroke and Type 2 diabetes. Limitations of BMI Body fat percentage is a body composition measurement. Bear in mind that not all fat is visible, so you could have more of it than you think. Visceral fat is stored within the abdominal area and surrounds important organs, including the liver, stomach, and intestines. It can also build up in the arteries and increases the risk of serious health problems. FIGURE S3 Comparison of 2D turbo spin echo water and fat images of the knee obtained using fat-saturation and water-saturation (top row), Dixon (middle row), and SMURF methods (bottom row) for the two volunteers not shown in the main manuscript (Figure 6). There is a high level of consistency between the methods. SMURF water images show slightly higher signal in fatty-tissue areas (eg, bones, subcutaneous fat), however, the acquisition time with SMURF was half of that with Dixon and with separate acquisitions with fat-saturation and water-saturation respectively. (The same non-linear grey scales were used for all fat and all water images.) Use day and night on clean, dry skin. Apply to palms, then pat and press over your face; letting it absorb