How is an MRI Scan Performed?

An MRI or Magnetic Resonance Imaging is a medical technique used mainly to click images of the internal organs of the body. Professionals use magnetic radio waves through advanced computers to get pictures of the internal organs of the body in this process.

The MRI machines are usually tube-shaped and large. When you are lying inside the MRI machine, the magnets act together to re-arrange the water molecules of the body. The radio waves enable the newly arranged atoms to transmit signals. Now, there is a creation of cross-sectional images. The MRI machine is so advanced that it can also produce 3D pictures that doctors can view from all angles.

An MRI is usually painless and takes about 15 minutes to 1 and a half hours to complete. The time varies depending on the size of the organ under the scan and number of pictures to capture. This article is all about how an MRI scan is performed, so read ahead to know it all.

What happens before the scan?

Usually, on the day of the scan, there will be no restriction on what you eat or drink. However, there can be exceptions if the doctor specifies some limits. You can also take your regular medicines on the day of the MRI scan.

Several times we can see that the doctor tells you strictly not to eat or drink anything for about 5 hours before the scan. While at other times, the doctor may ask you to drink more water before the scan. All these instructions generally vary from time to time and depend on the part of the body you need to scan.

As soon as you check into the hospital, you will get a questionnaire with some basic questions. You must fill in all the details and then only can the staff move you to the scanning lab. Such inquiries are necessary because it is like a physical biodata that you are giving the hospital officials about yourself. The end of the questionnaire is usually the consent form without which the scan cannot start.

As you already know that MRI scan requires the use of magnetic components, it is a must that you remove all the metallic objects before going for the scan. You must remove-

  • Watches
  • Hair wigs
  • Any jewelry
  • Hearing aids
  • Dentures
  • Piercings

There are usually secure lockers to store all your valuables while you are getting the scan done. You may also have to put on a hospital gown in some cases if the doctor tells you to wear it. If you are wearing everyday casuals, make sure that you do not have any zippers, buckles, fasteners, belts, wired bras, and buttons.

Contrast Dye Injection

Before some MRI scans, you need to take an injection of contrast dye. As a result, blood vessels and tissues become more visible under the scan. However, there are some side-effects of the contrast dye injection, such as:

  • Sickness
  • Dizziness
  • Headaches
  • Skin rashes

The side effects of the dose are usually not very serious, and only last until some time. However, taking this lightly is not wise. Such side-effects may sometimes lead to damage of organs and tissues. There are also reports of kidney problems due to the contrast dye injection.

If you are already suffering from any kidney disease, you will first have to get a blood test done. The results of the blood test will finally confirm if you are fit enough to get the scans done. The blood test report is a signal of whether your kidneys are functioning correctly or not. Also, before they push the injection, let the hospital staff know if you are prone to allergies or not. Any blood clotting problems should also be reported to the doctors immediately.

Sedatives and anesthesia

As you already know that an MRI scan usually is a painless method and so there is no requirement of anesthesia at all. in case you have claustrophobia, the doctor may give you a mild sedative so that you can stay calm. You should be clear about every detail and have a good discussion with the physician or consultant well before the scan.

In case you require sedatives before and during the scan, it is not safe that you drive home all by yourself. There should be someone who will pick you up from the hospital after the scan. Not only after the scan, but you are also not allowed to drive for the next day or 24 hours at least. 

Usually, young children and babies are restless, and so some mild and general anesthetics before the MRI scans are allowed for them. If the kids are awake, it is difficult to keep patience with them easily.

What happens during the scan?

The scanner is like a small cylinder that is kept open at both ends. There is a motorized bed, and you will have to lie down on that. Now you will be put inside the MRI machine for the scanning. Depending on what part of the body needs scanning, either your head goes in first or feet. Moreover, there are cases when a unique frame is placed on top of a particular organ. It can be the chest or the head and makes the scanning process easy.

The structure that is on top of you has a machine or tools in it. The devices will catch signals and transmit them to the central system. The computer will receive more explicit pictures in this case. The central equipment that is used to conduct the test is not kept in the same room due to the emission of radioactive energy. The radiographer will also not remain in the same place while monitoring you. However, you can communicate during any time of the scan. Headphones are allowed even inside the MRI scanner.

What happens after the scan?

Like you already know, MRI scans are outpatient procedures, and you will get a release right after the scan. Make sure you do not drive back if you have had sedatives for the scan. Do not drink alcohol or lift heavy objects for 24 hours at least after the scan. You will finally get your reports after about 1-2 weeks.

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