Article Abstract

Abdominal CT protocol’s influence on postoperative follow-up of lesions detection associated with gastrointestinal tumours

Authors: Jing-Feng Zhang, Chuan-Gen Guo, Jin-Sheng Liao, Qi-Dong Wang, Bai-Shu Zhong, Jian-Hua Yan


Background: Postoperative abdominal computed tomography (CT) follow-up for gastrointestinal tumours is used to monitor therapeutic effects and detect relevant lesions, while the effective dose (ED) associated with dual-phase enhanced CT (DPCT) can be more than 20 mSv. In this study, we investigated the diagnostic utility of abdominal CT protocols based upon radiation dose control.
Methods: In this institutional ethics review board-approved retrospective study, the electronic pathology database in authors’ hospital was searched for all cases of gastrointestinal tumours from June 2016 to June 2017, yielding 200 cases with complete information of clinical history and CT examination. CT scans were separated into six groups, including non-enhanced CT (NECT), arterial phase contrast-enhanced CT (APCT), venous phase contrast-enhanced CT (VPCT), NECT + APCT, NECT + VPCT and NECT + DPCT. ED was calculated for each group, and the detectability of relevant lesions was compared.
Results: The ED of NECT, APCT, VPCT, NECT + APCT, NECT + VPCT and NECT + DPCT were 7.27±1.64, 7.32±1.65, 9.17±2.07, 14.55±3.29, 16.41±3.71 and 23.70±5.36 mSv, respectively. The six groups according to CT protocols showed no signi cant differences in the detection of anastomosis. For the detectability of metastatic lesions, VPCT is equivalent to NECT + DPCT. In addition, VPCT is comparable to NECT + APCT in nding lymphadenopathy.
Conclusions: Postoperative VPCT follow-up for gastrointestinal tumours is comparable to conventional NECT + DPCT in the detection of relevant lesions postoperatively. The radiation dose of single VPCT is 62% less than NECT + DPCT.