Can magnets show what’s inside my body?

Magnetic Power in Medical Science!

One of the most widely used scientific instruments, the magnet, is used in many fields including that of medical science. Due to its magnetic resonance power, it has become a handy tool for detection of ailments.

Surprised by such a unique usage of the magnetic power? Well, read on to know more!


Magnetic Resonance

The power of a magnet is showcased by its ability to deflect or attract an object by means of its magnetic field. Similarly, magnetic resonance relates to the capability of a specific electromagnetic radiation within its magnetic field to excite even the fundamental atomic constituents of it.

In simpler words, it is the response, at the molecular level, of the constituents of an object, when it comes near a magnetic field.

It is this very form of the magnetic power that is used in medical procedures.

Magnetic Resonance Imaging

The process in which the property of magnetic resonance comes in handy in the field of medicine is in MRI (Magnetic  Resonance Imaging). This is used by the doctors to see the inside of your body. A type of test itself, the MRI scan utilises this resonance power to see inside the human body. It can then create a three-dimensional representation of the interior of our body for a clearer diagnosis.

In an MRI scan, this resonance power of the magnet as emitted by the machine aligns the protons of the body with the magnetic field. This alignment creates a magnetic vector. Now, as the individual is exposed to a radio wave frequency (RF), these magnetic vectors are deflected. Once the RF source is turned off, the magnetic vectors return to their original position and a radio wave is emitted and it is this wave that is used to produce the final MRI image.

What’s its like to have an MRI Scan?

An MRI scan will normally take the image of your entire body or just a specific part, such as your brain. In either case, an enlarged image will be created by the computer.

The procedure for this scan is quite simple. The patient simply has to lie down inside this tunnel type MRI machine. The tunnel comprises a huge magnet that is responsible for producing a very strong electromagnetic field. The machine then gradually moves inwards and outwards while the scanner placed in it scans the body. The machine may make some noise, but the procedure is entirely harmless to the patient.

How else we can see inside the body?

Other than an MRI scan, there can be two ways through which we can see inside our body. It could be either through an X-Ray or through an Ultrasound.

Both these methods are similar in a way that all of these use radiations to create images of the inside of the body. Unlike a scanner which simply creates images of the affected body part, these use radiations of different kinds to produce the images.

An X-ray is generally used to detect what is wrong inside the bones, or tissues. The X-ray machine uses electromagnetic radiation which penetrates the skin to reflect what’s inside.

Ultrasound on the other hand uses radiations of the ultrasonic frequency to detect the inside of the body. Usually, this process is used to check any illness in the abdominal area of a person. It is also used to detect a foetus inside the woman’s womb.

The MRI Scanner

The device, i.e. the MRI scanner appears like a long tunnel, inside which the patient is made to lie down on. A patient has to remain very still during the scanning process in order to produce a good, focused image. The scanner then moves up and down vertically, above the body. Though the machine does make a lot of noise as it works and vibrates a bit too, it does not hurt the patient in any way during the entire procedure.

Findings Of The MRI Scanner

The MRI machine does not take one whole image of the body. Instead the pictures are simply fragments of image of a specific portion of the body. The computer connected to the machine arranges all the pictures in order, such that a whole human figure representation is attained in 3D.

Another interesting point to note is that while different parts of the body reflect back to the machine a rather different frequency of radio signals, the computer system enlists different colours of representation for each tissue and organ.

Fun Facts

  • The primary magnet in a MRI machine is said to be able to create a magnetic field stronger than that of the Earth’s magnetic field.
  • When in an MRI scan, the patient should not wear anything metallic, like rings, earrings, etc. that is magnetic.

Related questions

  1. What are the other possible ways of scanning in medical health?
  2. Can an MRI reduce the chances of surgeries ?
  3. What other kinds of radiations are useful in the medical field ?

Objective Quiz

MRI stands for:

  • Magnetic Radiation Imaging
  • Magnetic Repulsion Imaging
  • Magnetic Resonance Imaging
  • None of the above

Each body part radiates a different wavelength of signal in an MRI scan:

  • causing different colour representation of each of them
  • causing partial images of each of them
  • causing enlarged image of each of them

The final image created in an MRI scan is :

  • 1D
  • 2D
  • 3D
  • 4D

MRI studies in detail:

  • each body part
  • each organ
  • only heart
  • only lungs

The primary magnet of an MRI scan machine:

  • has a magnetic field powerful than that of Earth itself
  • has a weak magnetic field, harmless to the body
  • none of the above

True Or False

  1. MRI scan is painless: ______
  2. Electromagnetic radiation is the fundamental principle of MRI: ______
  3. It is adviceable for the patient to not wear anything metallic during a MRI scan: _____
  4. MRI only creates partial images of the body: _________
  5. The MRI machine has a long tunnel-like shape:  ______

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