Establishing updated diagnostic reference levels for interventional radiology: a national Italian survey...

The implementation of Euratom Council Directive 2013/59 into Italian legislation (D. Lgs 101/2020) requires the Ministry of Health, in collaboration with the Istituto Superiore di Sanità (ISS) and relevant scientific organizations, to facilitate the evaluation and regular updating of Diagnostic Reference Levels (DRLs) for procedures in diagnostic and interventional radiology.

This study presents the update of the Italian Diagnostic Reference Levels derived from a survey conducted between 2019 and 2022 by a Working Group (WG) organized by ISS. A total of 53 hospitals across Italy were involved, of which 38 contributed to data collection related to body procedures. The survey concerned the collection of data related to different interventional radiology procedures: Trans-Arterial Chemo Embolization (TACE), EndoVascular Aneurysms Repair (EVAR), Transjugular Intrahepatic Porto-systemic Shunt (TIPS), Angioplasty and stenting for peripheral arterial disease of the lower limbs (LL), Percutaneous Biliary Interventions (PBI), Endoscopic Retrograde Cholangio-Pancreatography (ERCP), PTA (Percutaneous Transluminal Angioplasty) and/or Carotid stenting and Vertebroplasty. For each procedure, Air Kerma AT REFERENCE POINT(K_a,r), Kerma Area Product (P_KA) and Fluoroscopy Time (FT) were collected. Clinical parameters were obtained for TACE, EVAR, PBI, LL and Vertebroplasty, too. A P_KA multivariable analysis was performed to identify which parameters significantly influence the dosimetric data and to derive DRL related to procedure complexity.

New DRL values were derived for each of these procedures, except for TIPS, for which the typical value was used: 45 Gy.cm² for PBI, 24 Gy.cm² for LL, 62 Gy.cm² for PTA and/or Carotid stenting, 252 Gy.cm² for TIPS, 18 Gy.cm² for ERCP, 134 Gy.cm² for EVAR, 91 Gy.cm² for Vertebroplasty and 255 Gy.cm² for TACE. DRL were also established according to the complexity of the procedure for TACE and EVAR.

This national survey successfully established diagnostic reference levels (DRLs) for seven interventional body procedures (TACE, EVAR, TIPS, LL, PBI, ERCP, PTA, Vertebroplasty) across Italian hospitals, providing facilities with systematic tools to optimize patient radiation exposure through comparison with national values and complexity-stratified reference levels.