Differences Between A CT Scan and An MRI Scan

What is a CT scan? A CT scan is an imaging technique that uses a series of X-rays taken at different cross-sectional angles to create x-ray images on a CT scan computer. CT scan as it stands for Computerized Tomography Scan also called as Computerized Axial Tomography. A CT scan machine uses a form of electromagnetic radiation to create multiple cross sections images of our body. CT scan works by taking multiple cross-sectional images of the body at different angles using X-rays and then acquires these x-rays to form 3-dimensional images of a particular body part which is being scanned. A CT scan console examines all the X-rays taken at various angles and synthesize the images to form a 3-dimensional images of body organs. CT scan is useful in diagnosing some of the following conditions:

• Tumours
• Stroke
• Fractures
• Internal Bleeds
• Cancer Monitoring and Development

What is an MRI Scan? An MRI is a diagnostic imaging tool that uses strong magnetic waves to produce 3 dimensional images of the body. It uses radio waves to create in depth detailed images of bones, tissues and organs. In an MRI Scan machine, the superconducting magnet sends radio frequency waves inside the body. The magnetic field inside the human body aligns the atoms either in the north and south direction with few numbers of atoms remains unmatched and keeps spinning. When a radio frequency wave is sent from the MRI scanner, the unmatched atoms start spinning in opposite direction and when the radio frequency wave is stopped those unmatched atoms return to the normal position emitting out the energy in the form of a signal. This signal is received by the computer and the computer uses mathematical algorithms to convert the signal into an MRI Image. MRI scan is useful in diagnosing some of the following conditions:

• Herniated disks
• Torn ligaments
• Soft tissue issues
• Inflammatory bowel conditions
• Joint abnormalities.

CT SCAN Vs. MRI SCAN

• Technique: One of the major differences is that CT scan uses X-rays to create images of the body while MRI scan uses radio waves to produce detail images of the body.
• Scan Time: The time required for a CT scan is much less compared to MRI scan, But the scan time also depends on the different part of the body and also on the contrast scan.
• Image Quality: The MRI scan produce more sharp and more detailed images of the tissues and bones as compared to CT scan which may block certain parts of the body.
• Affordability: The MRI Scan is costlier than a of CT scan depending on the advancement of technology. A CT Scan is usually done in half the cost of the MRI scan.
• Sound Intensity: An MRI Scan generates more noise because of the strong magnets used in the machine and it requires earplugs to reduce the intensity of the sound. Whereas, CT Scan is much quieter than MRIs and therefore does not require any earplugs.
• Risk Factor: CT scan are quick, painless and non-invasive procedure, while MRI scan are non-invasive, noisy and takes more time. In MRI scan, the patient may tend to feel anxiety and Claustrophobic due to the small compact machine bore and long scan time.

Safety Precautions: MRI scan tend to involve safety concerns as the patient have to take special precautions before entering the MRI room (remove all the metal objects). While CT scan is a risk-free scan as it does not involve any safety precautions to be taken.

Which scan is Safe for the patient?

CT scan and MRI scan are comparatively safe scan and largely performed on patients for diagnosing the condition. They may possess certain risk which will differ on the types of scan performed. CT scan involves small amount of radiation which is not as much harmful to the patient, MRI scan does not involve any radiation and are comparatively safer than CT scan. As MRI scan uses strong magnets to produce radio waves, there is a risk in going for an MRI scan wearing any metal objects. Therefore, certain precautions are mandatory before an MRI scan. Patients with pacemakers and any other newer metallic implants can cause problem in MRI scan and may tend to risk the patient because of the strong magnets. MRI scan is done in a metal free environment. In case of pregnancy, CT scan are not recommended as even a small amount of radiation can harm a new born child. In such case, MRI and Ultrasound scan is mostly preferred, still MRI can be avoided as a precaution specially in 1st and 2nd trimester.

Advantages of CT scan and MRI Scan

1. One of the best advantages of a CT scan than an MRI scan is quick scanning time, which is most important in the case of Stroke where an urgent conclusion is required whether it is Haemorrhagic or non-haemorrhagic infarct. 
2. CT scan is useful in Diagnosing and Staging of Cancer, it is most efficacious in the growth of the cancer treatment and also in recurring of cancer.
3. CT scan is faster than MRI and it scan the entire body in quick time, it is helpful in cancer cases where an entire body examination is required for the spread of cancer in lungs, liver, soft tissues, etc. 
4. An MRI scan surpasses the CT scan, in terms of the image quality showing certain diseases that a CT scan cannot detect. For example, a lumbar spine MRI scan shows more detailed images of herniated disks whereas not showing the details in CT scan. 
5. Certain cancers like Prostate cancer, liver cancer, Uterine cancers and rectum cancer which are hardly visible in CT scan are most likely to be seen in detail in an MRI scan.

Disadvantages of CT scan and MRI Scan

1. CT scan involves electromagnetic radiation which is quite more than an X-ray machine, but it is in small doses given to the patient. If these small doses are taken by the patient for a lifetime, there is a very slight risk of developing cancer.
2. In MRI scan, it takes a long period for any scan to be performed and the patient has to lie without moving in a small compact machine bore, there are chances that the patient develops symptoms of anxiety and claustrophobia.  In order to have a complete healthcare imaging solution, most Hospitals and Diagnostics prefer both the CT scan and MRI scan as the Standard Diagnostic tools which mainly promotes in the patient`s diagnosis and treatment. Although, an MRI solution breakthrough CT scan in some cases, But it is preferred based on the patients condition and treatment to be followed.

References:

1. Medicalnewstoday.com
2. Healthline.com
3. Medicinenet.com
4. Mskcc.org

Kryptonite solution