What’s the difference between a CAT-Scan and a CT-Scan?

In the medical field, a diagnostic exam is any kind of medical exam performed to aid in the diagnosis or detection of disease. Various procedures, like MRI, x-ray, ultrasound, nuclear medicine and other scans, help doctors and medical professionals diagnose diseases and see illness growth. A CT-scan is a widely used diagnostic exam preformed all over the world. This exam has been associated with a CAT-Scan. Are these two exams different or are they the same?

The answer is they are the same. In its early beginning, it wasn’t called CAT-Scan or CT-Scan but was known as an EMI scan, named for the EMI Company that developed and originated the equipment. The equipment makes use of computer-processed combinations of many x-ray images taken from different angles to produce cross-sectional (tomographic) images (virtual ‘slices’) of specific areas of a scanned object, allowing the user to see inside the object without cutting.

So, CAT and CT scans both mean the same type of diagnostic examination. CAT was used earlier in its history, while CT is the recent up-to-date term for convenience sake. The term CT stands for computed tomography and the term CAT stands for computed axial tomography or computerized axial tomography scan. Even though CT-scan is the more modern term, some medical professionals still use the term CAT-scan.

Contributions by Erica L. Gates, Radiology CT Manager.

Glenn Miñano

About the Author: Glenn Miñano

Glenn Miñano is a media specialist in the Department of Radiology, providing graphic design, photography, printing, video services, and administration of the department’s online properties. His works have been published in several medical articles, such as the American Journal of Radiology and the American Institute of Ultrasound. He has been providing these services to the Radiology Department since 1996.

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  1. Barbara August 29, 00:55
    Does a ct scan show fleshly parts or is it just bone structure
    • Alex Towbin
      Alex Towbin September 03, 16:51
      Thanks for the question! CT lets us see both the bones and the soft tissue part of the body. CT is often compared to MRI. In that comparison, CT does a better job of seeing certain body parts like the lungs or the appendix. MRI lets us see the soft tissue a little differently and is a better test to see the detail of certain soft tissue structures such as the ligaments of a joint or the different parts of the brain.