SOMATOM Definition Dual Energy Scanning

Author: Satoru Kitano MD, Nagaaki Marugami MD, Toshiaki Taoka PhD MD, Kimihiko Kichikawa PhD MD
Department of Radiology, Nara Medical University, Nara / Japan

History

A 55 year-old male was referred to a Dual Source CT follow-up scan after transcatheter arterial chemoembolization (TACE) of his hepatocellular carcinoma 6 years ago. A contrast enhanced dynamic CT scan of the abdomen was performed on the SOMATOM Definition using spiral Dual Energy evaluation.

Diagnosis

The hepatic arterial-dominant phase images revealed numerous hyper-attenuating lesions. From these dual energy images, virtual non contrast images were generated with a colored iodine overlay that could be phased in and out. The lesions, detected in S4 of the liver, showed the same hypo-attenuation in the virtual non-contrast and in the native CT images and the colored iodine overlay allowed a clear analysis of the iodine uptake in the lesions. The patient was diagnosed with multiple HCC recurrence with liver cirrhosis.

Comments

In the Dual Energy mode, two x-ray sources can be operated simultaneously at different kV levels. The results are two spiral data sets acquired in a single scan providing diverse information that allows one to differentiate, characterize, isolate, and distinguish the imaged tissue and material. Enhancement patterns of liver lesions can clearly be visualized with the Dual Energy Liver VNC application.

Dual Energy Virtual Non Contrast application visualizes: non contrast and pure iodine.
Non contrast, mixed 50/50 virtual non contrast/iodine and colored iodine display.

Examination Protocol