CAT Scan and CT Exam Are the Same Thing
Yes, a CAT scan and a CT exam are identical—they refer to the same imaging modality. The term "CAT" stands for Computerized Axial Tomography, while "CT" stands for Computed Tomography, and both describe the exact same diagnostic imaging technique 1.
Historical Terminology Evolution
The original terminology was "CAT scan" (Computerized Axial Tomography), which emphasized the axial plane acquisition method used in early scanners 1.
Modern terminology has shifted to simply "CT" (Computed Tomography) as the technology evolved beyond purely axial acquisitions to include helical/spiral and multidetector techniques 2, 3.
Both terms remain clinically acceptable and interchangeable, though "CT" is now the predominant term in contemporary medical literature and practice 1.
Technical Definition (Applies to Both Terms)
Both CAT and CT describe the same imaging process: recording two-dimensional x-ray images from various angles around an object, followed by digital three-dimensional reconstruction 1.
The technology uses x-ray attenuation principles to create cross-sectional images with high spatial resolution, allowing multidirectional examination of anatomical structures 1, 3.
Modern CT/CAT scanners achieve 95-98% diagnostic accuracy for detecting lesions versus no lesion, making it one of the most important advances in diagnostic radiology 4.
Clinical Practice Implications
When ordering imaging, use "CT" as the standard terminology, as this is what appears in contemporary guidelines and appropriateness criteria from the American College of Radiology 1.
If a patient or referring provider uses "CAT scan," recognize this as requesting the same examination and proceed with standard CT protocols 1.
The specific type of CT matters more than the terminology—distinguish between non-contrast CT, CT with contrast, and CT angiography (CTA), as these require different protocols and provide different diagnostic information 1, 5.