Phantom-based radiation dose assessment in abdominal spectral CT imaging
10.3760/cma.j.cn112271-20240808-00300
- VernacularTitle:腹部能谱CT成像辐射剂量评估的体模研究
- Author:
Hui QI
1
;
Ping FANG
;
Dingye CUI
;
Guangying ZHENG
;
Wei LI
Author Information
1. 山东第一医科大学第一附属医院（山东省千佛山医院）放射科 山东省肺癌研究所 山东省神经免疫研究所，济南 250014
- Publication Type:Journal Article
- Keywords:
Automatic spectral imaging protocol selection;
Spectral CT;
Phantom;
Radiation dose
- From:
Chinese Journal of Radiological Medicine and Protection
2025;45(5):478-484
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To assess the impacts of abdominal spectral computed tomography (CT) scans on radiation dose in order to validate the feasibility of low-dose spectral CT imaging.Methods:Using varying scanning protocols on the Discovery CT750 HD device, the abdomen of an adult male dose-specific phantom was scanned in two modes: conventional single-energy CT (SECT) and gemstone spectral imaging (GSI). Specifically, the conventional SECT mode featured tube voltages of 120 and 80 kVp, automatic tube current modulation technology, and a noise index (NI) of 10 HU. In contrast, the GSI mode was characterized by the automatic spectral imaging protocol selection (ASIS) technique, rapid switching of the tube voltage between 80 and 140 kVp, and Nis for non-spectral scanning of 8, 10, 15, and 20 HU. Then, various radiation dose metrics and objective image quality were compared across different scanning protocols.Results:In the case of the same NI, the three scanning dose modes (SECT with tube voltages of 120 and 80 kVp, and GSI with a tube voltage of 80/140 kVp) presented similar volume CT dose index (CTDI vol) and dose length product (DLP). However, the SECT with a tube voltage of 80 kVp showed the lowest measured organ absorbed dose ( DT; 5.89 mSv). Effective dose ( E) was determined using DLP and organ DT. The result indicated that, under the three modes except for SECT with a tube voltage of 80 kVp, the E values calculated using DLP were lower than those determinized using the organ DT, with deviations ranging from 9% to 20%. The differences in image noise levels and signal-to-noise ratios (SNR) of the three scanning modes were statistically significant ( F = 65.52, 35.09, P < 0.001). Conclusions:Spectral CT using ASIS technology can achieve low-dose spectral scanning while ensuring image quality.
