Radiology Terms


What Is Dual Energy CT?

Dual-energy (or dual-energy CT) refers to a special type of CT scan, also known as a spectral CT. Images are captured using two different energies of X-rays. Standard CT scans create cross-sectional slices or pictures of the tissues, using normal X-rays. A dual-energy CT uses both a normal X-ray and a less powerful X-ray to create the image. 

The advantage of using a dual-energy CT is that it can increase the clarity of some abnormalities by dialing up or down the effects that substances like contrast dye have in the body. That makes it easier to obtain images with and without the dye’s effect in one scan, rather than performing the scan twice. It is sometimes used for patients with kidney stones to help identify the type of stone present, and for patients with metal in the scanned area, including joint replacements. The patient does not experience any difference in the scanning process compared to a regular CT scan.