Exposure Monitoring and Dosimetry - Optimizing Radiation Protection in Interventional Cardiology

Abstract: During interventional cardiology (IC), medical staff are exposed to scattered ionizing radiation from the patient, potentially leading to various radiation-induced health effects. Therefore, shielding devices are routinely used to reduce occupational exposure during IC procedures. This study explores how the positioning of shielding devices impacts radiation protection efficiency in clinical scenarios. The study aims to determine optimal setups and potential pitfalls that might significantly reduce the efficiency of the shielding devices. It also explores the relationship between DICOM-based production data, clinical observations, and phantom-based measurements to add knowledge to the research field of radiation protection in IC. Clinical DICOM-based production data from 4976 procedures were analyzed to identify C-arm projection angles used during different procedure types. This data and the results of an observational study were used to determine a scattered radiation measurement setup. A survey meter was used to measure air kerma at seven heights in the operator position while an anthropomorphic phantom was irradiated. The measurements were distributed over seven projections with 56 position combinations of the shielding devices. A total of 3171 measurements were performed. The measurements suggest significant variations in the operator dose depending on the projection and how the shielding devices are positioned. The most optimal combination of shielding devices was achieved when placing the table-mounted shield along the table, the ceiling-suspended shield caudal close to the phantom, and without the patient drape. Conversely, the least optimal combination was achieved when placing the table-mounted shield flared out, the ceiling-suspended shield cranial 10 cm above the phantom, and without the patient drape. The air kerma rate for these two shielding setups with the LAO25/CAUD30 projection was reduced from 0.19 μGy/s to 0.05 μGy/s at 110 cm from the floor. This height was shown to be the hardest to properly shield. Despite the implementation of the most optimal shielding combination, it is evident that certain heights present difficulties in effectively protecting the operator from scattered radiation.