Magnetic Resonance Imaging.
Magnetic Resonance Imaging, also known as MRI scanning, is a painless type of scanning that uses a magnetic fields and radio waves and a computer to produce images of body structures in multiple planes. This type of scanning does not involve x-ray radiation, and in return, there is no risk of exposure to radiation during an MRI.
The following are examples in which an MRI scanner would be used:
- anomalies of the brain and spinal cord
- tumors, cysts, and other anomalies in various parts of the body
- breast cancer screening for women who face a high risk of breast cancer
- injuries or abnormalities of the joints, such as the back and knee
- Heart problems
- diseases of the liver and other abdominal organs
- the evaluation of pelvic pain in women, with causes including fibroids and endometriosis
- Very expensive
- Dangerous for patients with metallic devices placed within the body.
- Difficult to be perform on claustrophobic patient.
- Movement during scanning may cause blurry images.
- Involve really loud noises while processing.
Principle of MRI
- MRI makes use of the magnetic properties of certain atomic nuclei.
- Hydrogen nucleus (single proton) present in water molecules, and therefore in all body tissues.
- Radio frequency pulse emit a radio signal
- This is detected using antennas.
- Very detailed images can be made of soft tissues.
There is very little preparation required, if any, before an MRI scan.
On arrival at the hospital, radiologic technologist may ask the patient to change into a gown. As magnets are used, it is critical that no metal objects are present in the scanner. The radiologic technologist will ask the patient to remove any metal jewellery or accessories that might interfere with the machine.
A person will probably be unable to have an MRI if they have any metal inside their body, such as bullets, shrapnel or other metallic foreign bodies. This can also include medical devices, such as cochlear implants, aneurysm clips and pacemakers.
Individuals who are anxious or nervous about enclosed spaces should tell their doctor. Often they can be given medication prior to the MRI to help make the procedure more comfortable.
The radiologic technologist who specializes in medical images, will then talk the individual through the MRI scanning process and answer any questions they may have about the procedure.
Once the patient has entered the scanning room, the radiologic technologist will help them onto the scanner table to lie down. Staff will ensure that they are as comfortable as possible by providing blankets or cushions.
Earplugs or headphones will be provided to block out the loud noises of the scanner.
During an MRI scan
Once in the scanner, the MRI technician will communicate with the patient via the intercom to make sure that they are comfortable. They will not start the scan until the patient is ready.
During the scan, it is vital to stay still. Any movement will disrupt the images.
If the patient feels uncomfortable during the procedure, they can speak to the MRI technician via the intercom and request that the scan be stopped.
After an MRI scan
After the scan, the radiologist will examine the images to check whether any more are required. If the radiologist is satisfied, the patient can go home.