Dual Energy CT Systems (Not Photon Counting) 

Dual Energy CT Systems enable material specific imaging rather than traditional Hounsfield Units.
There are several CT scanner designs for achieving dual energy CT.
These include:
Fast kVp Switching
Deep Learning kVp Switching
Split Filter Systems
Dual Source CT
Dual Layer CT
Rotate-Rotate CT
We introduce the different CT system designs and compare them systematically.