National diagnostic reference levels in interventional radiology suites in Lebanon: a multicenter survey

Air kerma-area product (PKA), cumulative air kerma at patient entrance reference point, fluoroscopy time and number of images were retrospectively collected from 15 hospitals in Lebanon for 11282 fluoroscopically-guided interventional (FGI) procedures between March 2016 and November 2018. National diagnostic reference levels (NDRLs) were established based on the third quartile of the distribution of median values of exposure parameters per department for 27 types of FGI procedures. NDRLs were in line with international DRLs except for coronary angiography (CA), percutaneous coronary interventions (PCI) and transcatheter aortic valve implantation (TAVI) which require optimisation. Additionally, following the National Council on Radiation Protection and Measurements report 168, PCI, TAVI, triple chamber pacemaker implantation, endovascular aortic repair, nephrostomy, kyphoplasty and percutaneous transhepatic biliary drainage were classified as potentially high-dose procedures with >5% of the patients with PKA exceeding 300 Gycm2. The established NDRLs will promote dose optimisation and patient radiation protection.