How is CT Scan Different From MRI?

How is CT Scan Different From MRI?

| Imaging

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Through the use of MRI and CT scan, detailed images of internal body parts like joints, organs and bones are created. These are the two medical imaging methods that are used to diagnose a wide range of medical conditions. While both of them have similar uses, they apply different techniques to create images. Most people are confused about when to use a CT scan and when to opt for an MRI scan. So, today, we will explain the difference between their usage, their procedures, their costs, and much more. 

What is CT Scan? 

Generally, CT scan is also referred to as a CAT scan, which stands for computerized axial tomography. It is used to create images that detect abnormalities in bones and organs such as bone fractures, damaged joints and tumours on organs. 

 What is the Procedure?

During a CT scan, the patient lies down on a flat surface that moves though a scanning ring. X rays are passed through his body that creates cross-sectional images of the body. The patient needs to lay very still for the machine to take clear images. The x-ray data is processed by a computer to create either a 2-D or 3-D image. To avoid radiation, the technician leaves the room, but can still communicate with the person on the scanning table through the intercom. 

What is MRI Scan?

MRI stands for Magnetic Resonance Imaging. A powerful magnetic field, paired with radio waves is used to produce images of the human body in this imaging technique. Organs, soft tissues, bones, and other internal structures of the body can be viewed through the detailed images produced by this medical imaging method. 

What is the Procedure? 

A patient has to lie down on a moving table that slides down to the MRI machine. Traditionally, the whole set up looks like a tunnel. But these days, different MRI machines have come into the picture like Open Upright MRI and Wide-bore MRI, making patients more comfortable during the process.  

The superconducting magnet used in MRI lines up atoms in a straight line, either north or south direction, leaving a few atoms spinning like usual. These atoms stand out. When radio waves are introduced, these atoms spin in the opposite direction, and when the radio frequency is turned off, they return to their normal position, emitting energy in the process. This energy signal is sent to the computer which uses a mathematical formula to convert the signal into an image. 

CT Scan Vs MRI: 

Cost: MRIs cost more than CT scans. The machines are more expensive for the later as well as the running cost. 

Time: MRIs are slower than CT scans. Approximately 10 minutes are required for CT scans. The time may vary depending upon the body part being examined. MRIs take about 45 minutes to an hour, similarly depending upon the body part being examined. 

Accuracy: Both scans are handy diagnostic tools and are invaluable when it comes to monitoring diseases, injuries and other tissue abnormalities. However, an MRI scan takes a step further by scanning soft tissues better. However, the accuracy of the image depends on the technician’s ability to place the patient in the correct position for the scan. 

Safety: Generally, both these scans are safe. However, MRIs should never be done on people who have aneurysm clips, as they can be pulled off patients. Next, the people who have cardiac pacemakers can malfunction during the scan as they are battery-operated devices and interaction with the magnetic field can cause damage to the organ.

Patient Comfort: The CT scan machine is very open, so people don’t feel any discomforts in it. MRI machines, on the other hand, can cause anxiety in patients as the space in which the customer lays is narrow and usually, patients aren’t comfortable in it.


About Author

Dr. Jawad is a practicing physician with extensive administrative experience, who has firsthand knowledge of running a medical practice and working in employed models. WoW Health aligns incentives for the healthcare ecosystem so all stakeholders benefit from transparent and direct relationship between patients and medical service providers.