What does a radiologist do?

A radiologist is a doctor who specializes in medical imaging. They use different types of imaging to diagnose and treat various conditions and injuries.

A radiologist is a type of doctor who specializes in medical imaging. Radiologists analyze images, such as X-rays, to help diagnose, monitor, and treat various conditions or injuries. Radiologists are different than radiographers. Although both of these professionals work with medical imaging, radiographers are the people who operate the machinery. There are different types of radiologists, including diagnostic radiologists and medical physicists.


There are several different specialties of radiology, including:

Diagnostic radiologists use medical imaging to diagnose and treat diseases. They can use a variety of different imaging methods, such as:

  • X-rays

  • CT scans

  • MRI

  • Ultrasound

  • Mammography

Using these imaging methods, diagnostic radiologists are able to detect and diagnose a wide variety of diseases. In addition, they can also use these methods to treat diseases.

Interventional radiologists

Interventional radiologists use medical imaging to provide therapy, such as keyhole surgery, to people with noncancerous conditions. This imaging can make surgical procedures safer and lead to faster recovery times.

Radiation oncologist

A radiation oncologist uses radiation-based therapy to treat cancer. This therapy involves the use of high energy radiation to damage cancer cells and prevent them from spreading. It can help reduce symptoms or, in some cases, cure the condition entirely.

Medical physics

Medical physicists apply their knowledge of physics to help advance the field of medicine. This can take many forms, such as providing guidance on medical imaging and ensuring patient safety, or conducting research to develop new medical technologies. Many common devices and pieces of equipment used by doctors today were developed by medical physicists, such as MRI machines.

Radiologists can work in a variety of settings, including clinical practices, hospitals, and universities. Their job responsibilities vary depending on their specialty. All radiologists use medical imaging methods, such as:

  • Computed tomography (CT) scans

  • MRI scans

  • Positron emission tomography (PET) scans

  • X-rays

  • Ultrasounds

  • Nuclear medicine

  • Fusion imaging

Radiologists use techniques that mostly involve radiation in order to get images of the inside of the body. They are highly trained to make sure that the patient is safe from the harmful effects that radiation can have. Radiologists can help other doctors decide which imaging method to use and help them understand what the results from the imaging will mean for the treatment plan. They can also help to interpret different images and other test results in order to make a diagnosis or to monitor whether current treatments are working. There are certain types of radiologists, such as interventional radiologists, who are more actively involved in the treatment process. Others, such as diagnostic radiologists, might provide support to other healthcare professionals. Some radiologists rarely work with patients and instead work in labs doing research. For example, some clinical studies might include a radiologist to help with the analysis of medical images.


1. Brant WE, Helms CA. Fundamentals of Diagnostic Radiology. 5th ed. Philadelphia: Wolters Kluwer; 2018.

2. Herring W Jr. Learning Radiology: Recognizing the Basics. 4th ed. Philadelphia: Elsevier; 2016.

3. Sutton D. Textbook of Radiology and Imaging. 8th ed. Philadelphia: Churchill Livingstone; 2018.

4. Webb WR, Brant WE, Major NM, et al. Fundamentals of Body CT. 5th ed. Philadelphia: Elsevier; 2015.

5. Chen MY, Pope TL Jr, Ott DJ. Basic Radiology. 2nd ed. New York: McGraw-Hill; 2011.

6. Bushong SC. Radiologic Science for Technologists: Physics, Biology, and Protection. 11th ed. St. Louis: Elsevier; 2017.

7. Grainger RG, Allison D, Adam A, Dixon AK. Diagnostic Radiology: A Textbook of Medical Imaging. 7th ed. Philadelphia: Churchill Livingstone; 2017.

8. Squire LF, Novelline RA. Fundamentals of Radiology. 2nd ed. Cambridge: Harvard University Press; 2006.

9. Christensen JD, Linnau KF. Diagnostic Imaging: Emergency. 2nd ed. Salt Lake City: Amirsys; 2016.

10. Pellerito JS, Polak JF. Introduction to Vascular Ultrasonography. 6th ed. Philadelphia: Elsevier; 2012.