MRI stands for Magnetic Resonance Imaging. MRI is an imaging technique in medicine that uses magnetic fields and radio waves to get a detailed image of the anatomy and physiology of the body to detect any abnormalities. It is a far better imaging technique than an X-ray and CT Scan to diagnose any injury or pathology of the body. It is useful in getting a detailed picture of the soft tissues and the nervous system. MRI scan does not use powerful ionizing radiations hence they are considered safer than X-rays and CT scans. MRI came into existence somewhere around the 1970s and has proved to be a versatile option in detecting the pathology. Earlier, MRI was known as Nuclear Magnetic Resonance Imaging( NMRI ). The term nuclear was later removed because of its negative effect on people’s minds. MRI was invented by Raymond Damadian. In the year 1977, Damadian performed a full-body scan of the patient suspected of cancer. He thus invented the apparatus to use the concept of NMR safely upon the human body. This method gained vast popularity later by the name MRI.
The MRI scan would be useful in:
Its mostly used for scanning the Brain and Spinal Cord to detect any abnormality post any trauma or symptom due to an underlying pathology.
To detect breast cancer in females, cysts, or tumors in any part of the body.
To evaluate any heart problems.
In suspected uterine cases in females who have shown a history of irregular menses and infertility.
To detect any abdominal problem.
Concept of MRI:
MRI works on the concept of using a strong magnetic field that encourages the protons in our body to come in alignment with that field. When a radiofrequency is passed through the patient these protons get encouraged and spin out of their stable state against the pull of the magnetic field. After the radiofrequency is turned off, the sensors of the MRI detect the energy as the protons come back in alignment with the magnetic field. Thus with the help of the magnetic field and radio waves, the detailed images of the inside of the body are reflected. The difference between various types of tissues is made based on the magnetic properties.
Types of MRI Machine:
The MRI machines are basically classified into three varieties:
Extremity MRI: This MRI focuses upon the extremities of the body( arms and legs ). Usually, for the scanning of the whole body, a large tube-shaped device is used that has the capacity to accommodate the whole body and is capable of scanning every inch of the body, but in this case, a smaller scanner is designed to scan just the extremities of the body. This proves helpful in patients who have Claustrophobia which is a fear of being in an enclosed place.
Open MRI: An open MRI is designed to have wider openings that is open on sides but still, the patient has to lie on a sliding table. It is a much comfortable option for patients who have anxiety issues and are scared of being in enclosed spaces for long.
3 Tesla MRI: This type of MRI makes use of magnetic fields that are double the strength of the usual MRI thus producing much clearer images in lesser duration. It is mainly used to scan Brain to detect tumors, aneurysms, and Heart to detect any blockages in blood vessels.
Although MRI is a much safer option when compared to CT scan and X-rays, it too has some drawbacks like,
People who cannot tolerate loud noises feel it uneasy for the scan since the sound produced is more than 100 decibels in some scanners and hence special ear protection is required for the same.
People who have implants in the body like pacemakers or those particularly containing any kind of iron implants must not enter an MRI machine.
Pregnant women are not recommended to enter the MRI machine.
Patients who are Claustrophobic too will find it discomforting to enter into the MRI machine.
1. How Long Does it Take for an MRI Scan?
Ans: The scan can take from 10 minutes to an hour depending upon the part of the body to be scanned. The radiologist will priorly inform the patient how much time it is going to take to complete the MRI process.
2. Is MRI Harmful?
Ans: The magnetic field is not harmful. MRI is considered a safer option when compared to CT scan and X-ray. But any metal implants in the body may impose a risk. It is always advisable to inform the technician whether there are any metal implants in the body to avoid any kind of accident during the scan.