Do Endoscopic Ultrasound-Guided Transluminal Procedures Involve High Radiation Exposure?

Background: The ultrasound-based imaging procedures are known to be safer than those based on X-ray fluoroscopy as they do not involve ionising radiation. There is a natural tendency to look for ultrasound guidance wherever clinical needs can be met. While radiation exposure in endoscopic retrograde cholangiopancreatography (ERCP) has been evaluated, there is paucity of information on radiation doses in endoscopic ultrasound-guided transluminal drainage (EUS-D), which also utilises fluoroscopy in addition to ultrasound. In our study, we compared radiation exposures in EUS-D and ERCP. Methods: This retrospective, single-centre cohort study included consecutive EUS-D and ERCP performed between October 2017 and March 2019. The air kerma (Ka,r: mGy), kerma-area product (PKA: mGycm2), fluoroscopy time (FT: min), and procedure time (PT: min) were noted. The invasive probability weighting method was used to qualify comparison. Findings: In total 918 ERCPs and 105 EUS-Ds were enrolled. The median Ka,r, PKA, and FT in the EUS-D group were higher by 65%, 40%, and 40%, respectively, than those in the ERCP group, whereas PT was shorter by approximately 15% (Ka,r; 135·2 vs 82·5, PKA; 28275·0 vs 20399·9, FT; 20·4 vs 14·7, PT; 38·7 vs 45·2). Interpretation: This is the first report to assess radiation exposure in EUS-D and compare it with that in ERCP, which unexpectedly found that radiation exposure parameters were significantly higher in EUS-D than in ERCP, despite the shorter PT. This finding is of significance for future design of the equipment and for selection strategy for the procedure. Knowledge of these findings would raise awareness among endoscopists to minimise radiation risks to patients and staff. Funding Statement: There was no funding support for this study. Declaration of Interests: All authors had no conflicts of interest with other people or organisations. Ethics Approval Statement: The study protocol was approved by the Institutional Review Board of Kindai University (IRB No. R02-121). The study was conducted according to the provisions of the Declaration of Helsinki as revised in Fortleza, Brazil, in 2013.