Manuel Patino MD, Presenter: Nothing to Disclose

Jorge Mario Fuentes MD, Abstract Co-Author: Nothing to Disclose

Yasir Andrabi MD, MPH, Abstract Co-Author: Nothing to Disclose

Koichi Hayano MD, Abstract Co-Author: Nothing to Disclose

Mukta Dilipkumar Agrawal MBBS, MD, Abstract Co-Author: Nothing to Disclose

Dushyant V. Sahani MD, Abstract Co-Author: Research Grant, General Electric Company

Radiation dose remains a critical concern with the use of new CT techniques in the clinical practice. Therefore the purpose of the study is to compare Size Specific Dose Estimate (SSDE) between Single source Dual-energy (ssDECT) and Single-energy abdominal CT scans using current ACR-Dose Index Registry as reference standard.

A total of 150 patients with cancer history (61 Males, 89 Females) underwent a follow up CE-ssDECT (GE-CT750 HD, 140/80 kV; 375-630 mA) of the abdomen-pelvis. Their recent prior CE-SECT (16-64 MDCT, 120 kV; 41-531 mA) reconstructed using FBP in 84 patients and Iterative techniques in 65, served for dose estimate comparison. Size Specific Dose Estimate (SSDE) was calculated and compared between DECT and SECT using t-test. Dose Index Registry data was used as reference.

The mean SSDE on ssDECT, SECT-FBP and SECT-IRT were 15.6 mGy, 14.9 mGy and 12.1 mGy respectively. There was no significant difference in SSDE between DECT and SECT-FBP (p>0.05). A difference was found in SSDE between ssDECT and SECT-IRT (p<0.05). However, in comparison to the ACR-DIR data (19 mGy), the mean SSDE was 18% lower on ssDECT.

For cancer follow-up abdomen studies, the dose estimates from ssDECT are comparable to SECT-FBP and slightly higher than SECT-IRT but remain substantially lower than ACR-DIR data.

Dual energy CT has demonstrated added value in clinical diagnosis. However, radiation dose is still a critical concern that limits its wide implementation. This study shows comparable dose estimates between SECT and ssDECT, with minimally high SSDE in DECT, decreasing perceived radiation concerns.

Patino, M, Fuentes, J, Andrabi, Y, Hayano, K, Agrawal, M, Sahani, D, Dose Estimate Considerations in SECT and DECT of the Abdomen - Perceptions and Reality.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14014531.html