Name: using 23na magnetic resonance imaging to measure sodium in muscle tissues
Uploaded: 2024-02-29T13:13:38.000+00:00
Duration: 1 min 11 s
Description: All procedures involving human participants have been performed in compliance with the institutional, national, and international guidelines for human ...

sodium magnetic resonance imaging to measure tissue sodium content

Sodium Magnetic Resonance Imaging to Measure Tissue Sodium Content

Begin by embedding calibration standard sodium chloride solutions in the MRI phantom holder of the coil.
Position the participant on the MRI table in a supine position.
For imaging of the calf at the mid-gastrocnemius muscle, place the phantom holder inside the radiofrequency coil. Position the left lower leg over the phantom holder. Secure the top half of the radiofrequency coil in place.
For sodium imaging, use the three-dimensional gradient-echo sequence as described in the text protocol.
Further, acquire fat- and water-weighted images of the tissue using the mDixon protocol keeping the scanning parameters consistent. Complete the multinuclear exam of the lower extremity.
After the completion of the scan, calibrate the measured sodium signal intensities to the standard sodium chloride concentrations on a per-voxel basis.
Prepare a quantitative sodium map of the tissue and interpolate it to match the matrix size of the fat- and water-weighted mDixon images.
Select each region of interest on the water-weighted mDixon image. Further, segment the outer and inner borders of the skin, total muscle, bone, blood vessels, and subcutaneous adipose tissue. Segment the skin region further into the posterior semi-perimeter of the skin.
Remove the voxels from the bone and blood vessels from the analyses.
Obtain accurate muscle tissue sodium quantification.

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Using 23Na Magnetic Resonance Imaging to Measure Sodium in Muscle Tissues

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All procedures involving human participants have been performed in compliance with the institutional, national, and international guidelines for human welfare and have been reviewed by the local institutional review board.
1. Preparation of the phantom holder
<ol>
	<li>Four standard sodium solutions, including aqueous NaCl in the physiologic range of peripheral tissue sodium content 10-40 mmol/L, are embedded in a platform in the coil.</li>
</ol>
2. MRI examination
The quantification of Na+ content at the mid-calf area is measured using an MRI exam on a 3.0 T MR scanner (Philips Healthcare, Cleveland, OH, USA) and a single-tuned receive-only quadrature sodium coil (Rapid Biomedical GmbH, Rimpar, Germany).
<ol>
	<li>Place the participant in a supine position on the MRI patient table.</li>
	<li>For imaging of the calf at the mid gastrocnemius muscle, place the phantom holder inside the RF coil and rest the left lower leg on top of the phantom holder before closing the top half of the RF coil.</li>
	<li>Use the three-dimensional gradient-echo sequence as follows.</li>
	<li>Field of view = 192 &#215; 192 mm2, acquired matrix size = 64 &#215; 64, and slice thickness = 30 mm. A repetition time (TR) and echo time (TE) of 130/0.99 milliseconds is preferred to reduce error from residual T1 signal effects.</li>
	<li>Acquire fat and water images using the mDixon protocol, with matching field of view (FOV) and matrix size to the three-dimensional gradient-echo sequence.</li>
	<li>The sodium image acquisition time is approximately 15 minutes.</li>
	<li>The total multinuclear MRI exam of the lower extremity is approximately 30 minutes.</li>
</ol>
3. Image Analysis
<ol>
	<li>Measure the mean signal intensity in the standard sodium solutions.</li>
	<li>Calibrate the magnitude of sodium signal intensity to the standard sodium concentrations on a per-voxel basis.</li>
	<li>Make a quantitative sodium map and match the matrix size of the fat/water mDixon images.</li>
	<li>Segment each region of interest using the water image from mDixon, including the outer and inner borders of the skin, total muscle, bone, blood vessels, and sub-adipose tissue (SAT).</li>
	<li>Segment the skin region further into the posterior semiperimeter of the skin.</li>
	<li>Remove the voxels in the bone and blood vessels.</li>
	<li>Quantified metrics include Skin sodium (mM/L), SAT sodium (mM/L), Muscle sodium (mM/L), Circumference (cm), SAT volume (mm2), Muscle volume (mm2), Fat/Water ratio, and Fat Signal Fraction.</li>
</ol>

using 23na magnetic resonance imaging to measure sodium in muscle tissues

This video demonstrates the quantification of sodium content in human tissues using sodium magnetic resonance imaging (23Na-MRI). The patient&#39;s lower leg is placed within the radiofrequency (RF) coil of the machine, and a three-dimensional gradient-echo sequence is performed. Multinuclear MRI images are generated using hydrogen and sodium nuclei to quantify sodium levels in various tissues.

All procedures involving human participants have been performed in compliance with the institutional, national, and international guidelines for human ...

Place the patient&#39;s lower leg within the radiofrequency coil of the magnetic resonance imaging or MRI machine.
The coil contains various sodium concentrations as standards to measure tissue sodium accumulation.
Initiate a sodium-MRI scan.
The coil detects fluctuations in the MR signal intensity emitted from the tissue, influenced by the distribution and concentration of sodium ions. 
Obtain a total tissue sodium map displaying areas with varying color intensities corresponding to the sodium levels. 
Compare these intensities with standard sodium concentrations, which aid in measuring total tissue sodium levels. 
 Bright colors indicate higher levels, while darker colors indicate lower levels. 
 Next, capture signals corresponding to the fat and water content of the tissue to generate images of the non-muscle regions.
 Subtract non-muscle regions from the total tissue sodium map to generate a refined image and measure muscle tissue sodium content.

using-23na-magnetic-resonance-imaging-to-measure-sodium-muscle

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Using ²³Na Magnetic Resonance Imaging to Measure Sodium in Muscle Tissues

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