Difference Between CT Scan and Ultrasound

Doctors often use some type of diagnostic imaging for getting a better look at the bodies of their patients.

There are several types of diagnostic imaging tests and each of them develops pictures or images using different types of technologies.

These tests help doctors to make an accurate diagnosis and choose the proper treatment for their patients. CT Scan and Ultrasound are some of them.

CT Scan vs Ultrasound

The difference between CT scans and Ultrasound is that during CT scan a patient is exposed to effective radiation dose by passing through a scanning system. The radiation dose in CT scan ranges from 2 to 10 mSv. On the other hand, there is no radiation exposure in ultrasound, and the process is based on sound waves and echoes.

A CT scan generates high-quality images of the patient’s body. CT scan is considered a more sophisticated and powerful x-ray that takes 360-degree images of the vertebrae, spine, and other internal organs of the patient.

CT scan develops detailed, high-quality images of blood vessels, bones, soft tissues, and other internal organs, using which doctors can diagnose medical conditions like cancer, heart disease, and so on.

Ultrasound is another diagnostic tool that helps to see images of internal organs of the body, especially the joint structures. Ultrasound imaging or sonography uses high-frequency sound waves for creating a live video image of the internal organs of the body.

Ultrasound can capture the movements of the internal organs of the body as well as the flowing of blood through blood vessels as it captures real-time images of the body.

Comparison Table

Parameters of Comparison	CT Scan	Ultrasound
Purpose	CT scan can detect joint and bone problems, such as tumors and complex bone fractures, spot several medical conditions like heart disease, cancer, emphysema, etc. by using radiation waves.	Ultrasound uses high-frequency sound waves for creating a live video image of the internal organs of the body.
Application	CT scan is used to quickly examine the internal injuries from accidents or traumas. It is also used for visualizing all internal parts of the body that helps to diagnose certain types of benign and malignant tumors (cancer)and other medical conditions.	If patients have swelling or pain, doctors can use ultrasound for identifying abdominal problems in the stomach, appendix, liver, kidney, pancreas, and gallbladder; examining breast lump, and so on.
Advantages	Using CT scans doctors can see 360-degree images of internal parts of the body like soft tissue, bone, and blood vessels.	Ultrasound is used to see the live video image of the structure, size, and abnormalities in tendons, muscles, and other internal organs like kidneys, gall bladder, liver, appendix, and so on.
Time duration	CT scans generally take five minutes. Though the contrast-enhanced CT scan (CECT) demands more time.	Ultrasound takes more time compared to CT scan, it takes around fifteen to thirty minutes to complete.
History	CT scan was invented by Godfrey Hounsfield, an engineer, and Allan Cormack, a physicist in 1972. Initially, it is used to create images of the head.	There is controversy about the invention of ultrasound. Ultrasound is more old technology and Lazzaro Spallanzani is generally credited for inventing this technology in the late 1700s.

What is CT Scan?

CT scan or computed tomography scan is a diagnostic imaging tool that is used to detect injuries and diseases. CT scan uses a series of X-rays and a computer for producing a three-dimensional image of bones and soft tissues.

It is a non-invasive and painless way of diagnosing health conditions. Using CT scans doctors can see 360-degree images of internal parts of the body like soft tissue, bone, and blood vessels. 

CT scan was invented by Godfrey Hounsfield, an engineer, and Allan Cormack, a physicist in 1972. Initially, it is used for creating images of heads. CT scan generally takes five minutes.

Though the contrast-enhanced CT scan (CECT) demands more time. CT scan is used to quickly examine the internal injuries from accidents or traumas.

It is also used for visualizing all internal parts of the body that helps to diagnose certain types of benign and malignant tumors (cancer)and other medical conditions.

 There are very few risks in the process of CT scan. Though it exposes more radiation compared to other typical X-rays. If an individual has only one scan there is a very small risk of cancer. The risk of cancer increases over time if the number of scans increases.

What is Ultrasound?

Ultrasound is a diagnostic tool that captures live video images of internal parts of the body by using high-frequency sound waves. There is controversy about the invention of ultrasound.

Ultrasound is a more old technology and Lazzaro Spallanzani is generally credited for inventing this technology in the late 1700s.

If patients have swelling or pain, doctors can use ultrasound for identifying abdominal problems in the stomach, appendix, liver, kidney, pancreas, and gallbladder; examining breast lump, and so on.

Ultrasound is used to see the live video image of the structure, size, and abnormalities in tendons, muscles, and other internal organs like kidneys, gallbladder, liver, appendix, and so on.

Ultrasound is widely popular for assessing the growing fetus inside the womb of pregnant mothers. It is very helpful for diagnosing fetal anomalies or fetal abnormalities.

So, in this way, ultrasound helps in the early detection of congenital abnormalities. Ultrasound uses high-frequency sound waves for creating a live video image of the internal organs of the body.

Ultrasound is a painless procedure and there is no need for injections, needles, or other incisions. It is the safer diagnostic procedure as during ultrasound patients are not exposed to radiation.

There are a few known harms of ultrasound. It is less expensive and widely accessible compared to other diagnostic methods.  

Main Differences Between CT Scan and Ultrasound

1. CT scan can detect joint and bone problems, such as tumors and complex bone fractures, spot several medical conditions like heart disease, cancer, emphysema, etc. by using radiation waves.
3. On the other hand, Ultrasound uses high-frequency sound waves for creating a live video image of the internal organs of the body.
5. CT scan is used to quickly examine the internal injuries from accidents or traumas.
7. It is also used for visualizing all internal parts of the body that helps to diagnose certain types of benign and malignant tumors (cancer)and other medical conditions.
9. While, If patients have swelling or pain, doctors can use ultrasound for identifying abdominal problems in the stomach, appendix, liver, kidney, pancreas, and gallbladder; examining breast lump, and so on.
11. Using CT scans doctors can see 360-degree images of internal parts of the body like soft tissue, bone, and blood vessels.
13. Ultrasound is used for seeing the live video image of the structure, size, and abnormalities in tendons, muscles, and other internal organs like kidneys, gallbladder, liver, appendix, and so on.
15. CT scan generally takes five minutes. Though the contrast-enhanced CT scan (CECT) demands more time. Ultrasound takes more time compared to CT scan, it takes around fifteen to thirty minutes to complete.
17. CT scan was invented by Godfrey Hounsfield, an engineer, and Allan Cormack, a physicist in 1972. Initially, it is used to create images of the head.
19. There is controversy about the invention of ultrasound. Ultrasound is a more old technology and Lazzaro Spallanzani is generally credited for inventing this technology in the late 1700s.

References

1. https://www.sciencedirect.com/science/article/abs/pii/S0012369210604771
2. https://www.sciencedirect.com/science/article/pii/S0079610706000812