MRI Works under Minimally Invasive Procedure to Diagnose Cancer Effectively
The magnetic resonance imaging (MRI) or nuclear magnetic resonance imaging (NMRI) is an effective medical imaging technique. It is equally interesting to know how MRI works. This technique is commonly used in radiology to visualize the internal structure of the body. Unlike computed tomography (CT), it does not use ionizing radiation but a powerful magnetic field is used to align the nuclear magnetization of hydrogen atoms present in the water of the body. Physicians use radio frequency (RF) fields to modify the alignment of magnetization to produce information by which they can construct the images of the body organs.
It is the applied principle of Physics under which MRI works. The body is largely composed of water molecules which contain two hydrogen nuclei or protons. To understand the scanning procedure or to know how MRI works, physician lets the body go inside the powerful magnetic field of the scanner. The magnetic moments of these protons align with the direction of the field. Then a radio frequency electromagnetic field is turned on, causing the protons to manipulate their alignment relative to the field. And after turning off the electromagnetic field, the protons return to the original magnetization alignment. The changes created by alignment produce a signal which can be detected by the scanner. The frequency of the protons resonation depends on the strength of the magnetic field.
In this way, the position of the protons can be determined by applying additional magnetic fields during the scan to build an image of the body. Tumors or any diseased tissue can be detected through this process, as protons in different tissues return to their equilibrium state at different rates. Physicians can change the parameter on the scanner to create contrast between types of body tissue. There is also the option to inject contrast agents to enhance the appearance of blood vessels, tumors or inflammation. This is comparatively safe and minimally invasive treatment method to diagnose cancer or tumor in the body.