Effect of Copper Filtration on Radiation Dose in Cerebral Three-dimensional Rotational Angiography During Endovascular Aneurysm Treatment

Objectives: Cerebral angiography remains the gold standard for the diagnosis and endovascular management of cerebral aneurysms. Three-dimensional rotational angiography (3D-RA) provides superior anatomic resolution compared with conventional 2D imaging; however, it is associated with relatively high radiation exposure, raising specific concerns regarding the ocular lens dose. This study aims to evaluate the potential of copper (Cu) filtration for reducing radiation dose in 3D-RA. Materials and Methods: Forty subsequent patients undergoing endovascular treatment of unruptured cerebral aneurysms were included. All received 3D-RA using the ARTIS icono angiography system (Siemens Healthineers). In 20 patients, standard hardware with a 0.8 mm aluminum (Al) filter was applied; in the subsequent 20 patients, the Al filter was replaced by a 0.1 mm Cu filter. Image quality was assessed quantitatively through contrast-to-noise ratio (CNR) and qualitatively using a 5-point scale. Results: There were no differences in image quality between the two groups in the 3D neurovascular native/contrast images, both quantitatively (eg, mean CNR ± SD, Al: 20.72 ± 1.82 vs Cu: 20.66 ± 1.54; P = 0.93) and qualitatively (mean score ± SD, Al: 4.55 ± 0.54 vs Cu: 4.63 ± 0.46; P = 0.75), with excellent image quality achieved in both groups. Total radiation dose was lower with the Cu filter (e.g., mGy ± SD, Al: 110.63 ± 10.75 vs Cu: 68.70 ± 6.03; Gy·cm 2 ± SD, Al: 6.26 ± 1.57 vs 3.35 ± 0.67, P < 0.001 respectively), corresponding to a dose reduction of 38% (entrance-skin dose) and 46% (dose-area product). Conclusion: The use of a copper filter in cerebral 3D-RA substantially reduces radiation dose without compromising diagnostic quality, representing a practical advancement in patient safety in 3D-RA. The method integrates seamlessly into existing protocols and can be readily implemented in clinical practice.