Local Diagnostic Reference Levels in Interventional Radiology

Purpose: Interventional cardiology procedures, during which live images are acquired, involve exposure to x-rays. The use of fluoroscopy can cause high radiation doses to patients and operators because of the prolonged duration of x-ray emission. For this reason, special attention and constant vigilance represent challenges for commissions and groups of experts in the field. The purpose of this study is to establish local diagnostic reference levels (DRLs) for these procedures, to improve radiological practice, and to optimize radiation doses. Methods: This work was carried out in two university hospitals and two private medical facilities in Rabat, the capital of Morocco, during the period 2017–2018. The study concerns 657 interventional cardiology procedures (457 coronary angiography [CA] and 200 percutaneous transluminal coronary angioplasty [PTCA]), performed by 11 cardiologists on different installations in 5 catheterization rooms. The data collected for each procedure were patient age, height and weight, dosimeter indicators in terms of dose area product (P_KA), total air kerma at the reference point (K_ar), fluoroscopy time (FT), and the number of frames, together with the primary beam parameters as kV and total mAs. The proposed DRLs were set from the 75th percentile of the P_KA and FT. Results: The mean of P_KA for CA and PTCA procedures were 29.2 Gy∗cm² and 70.4 Gy∗cm², respectively, the mean of fluoroscopy time were 4.0 min and 12.17 min for 334 and 685 frames, respectively. Results for the local DRLs were 37.3 and 87.1 Gy cm² for P_KA and 4.48 and 16.15 min for FT, corresponding to CA and PTCA procedures. Conclusion: This work focuses on proposing local DRLs in Morocco for CA and PTCA procedures. The results show that the values found conform with those of international studies.