Knee Materials
MRI of the Knee
Materials utilized for the procedure
KC Hutchins
The materials used in the MRI of the knee are surface coils, volume coils, knee positioning pads, sandbags, and Gadolinium, in the case of a Magnetic Resonance Angiogram. Firstly, in some cases, a surface coil is used. They are of the simplest design, a loop of conducting material. It is used as a transmitter of radiofrequency energy. This receiver coil is placed on the region of interest or the knee, in this example, for greater magnetic sensitivity. It’s often used because it has a good signal to noise ratio for tissue next to the coil. However, the sensitivity will decline as the distance from the coil increases.
Next is volume coils, which surrounds the whole knee and is more commonly used for imaging of the knee because it gives better homogeneity, uniformity of the main magnetic field, of the radiofrequency in that region of interest than surface coils. Of all the designs, the birdcage coil is most commonly used because this transmit/receive type provides the best radiofrequency …show more content…
It’s used to help see blood vessels, inflammation, or masses. Being a positive contrast, it’s injected intravenously. The gadolinium contrast media is made from chemical bonds between a paramagnetic metal ion like Gadolinium(III) and a carrier molecule. The carrier molecule is a chelating agent where large molecules form a stable complex around the Gadolinium(III) ion. The gadolinium(III) ion is toxic in mammals. The chelating agent stops the toxicity of gadolinium but lets it keep its contrast properties. The chelated gadolinium(III) is carried to the kidneys and flushed out of the body before the free ion can get freed into the surrounding tissue, rendering it relatively harmless. There are different brands of Gadolinium contrasts that use different chelating
Materials utilized for the procedure
KC Hutchins
The materials used in the MRI of the knee are surface coils, volume coils, knee positioning pads, sandbags, and Gadolinium, in the case of a Magnetic Resonance Angiogram. Firstly, in some cases, a surface coil is used. They are of the simplest design, a loop of conducting material. It is used as a transmitter of radiofrequency energy. This receiver coil is placed on the region of interest or the knee, in this example, for greater magnetic sensitivity. It’s often used because it has a good signal to noise ratio for tissue next to the coil. However, the sensitivity will decline as the distance from the coil increases.
Next is volume coils, which surrounds the whole knee and is more commonly used for imaging of the knee because it gives better homogeneity, uniformity of the main magnetic field, of the radiofrequency in that region of interest than surface coils. Of all the designs, the birdcage coil is most commonly used because this transmit/receive type provides the best radiofrequency …show more content…
It’s used to help see blood vessels, inflammation, or masses. Being a positive contrast, it’s injected intravenously. The gadolinium contrast media is made from chemical bonds between a paramagnetic metal ion like Gadolinium(III) and a carrier molecule. The carrier molecule is a chelating agent where large molecules form a stable complex around the Gadolinium(III) ion. The gadolinium(III) ion is toxic in mammals. The chelating agent stops the toxicity of gadolinium but lets it keep its contrast properties. The chelated gadolinium(III) is carried to the kidneys and flushed out of the body before the free ion can get freed into the surrounding tissue, rendering it relatively harmless. There are different brands of Gadolinium contrasts that use different chelating