Assessment of DSA dose effect with different combinations of parameters on brain organs：a phantom study / 中华放射学杂志

ABSTRACT

Objective To investigate the lens and pituitary dose impacted by additional filtration and collection field in head and neck DSA examinations. Methods All images were acquired by a Philips ALLura Xper FD 20 DSA machine. The combination of the different collection fields (48 cm, 42 cm, 31 cm, 22 cm) and additional filtrations (0.9 mmCu+1.0 mmAl, 0.4 mmCu+1.0 mmAl, 0.1 mmCu+1.0 mmAl) were adjusted when the anthropomorphic phantom filled with dosimeter was scanned in anterioposterior and lateral positions with 2D?DSA and 3D?DSA. The dose area product (DAP), air kerma (AK) and the radiation dose values of bilateral lens and pituitary were measured and recorded. The 2D and 3D?DSA regional absorption dose on lens and pituitary were analyzed using t' test, the correlations between DAP and AK parameters and different regional absorption doses were evaluated by Pearson rank correlation coefficient. Results Absorption doses of left lens, right lens and pituitary with 2D?DSA (n=12) were as following(2.77 ± 0.68), (6.23 ± 3.54), (8.65 ± 2.62) mGy, while the parameters with 3D?DSA (n=12) were (1.78 ± 0.82), (2.18±1.15), (3.32±0.64) mGy, respectively;the results revealed a significant difference (t'=3.20, 3.76 and 6.85, P<0.01). DAP [(8 739±5 731) mGy·cm2] had a relationship with absorption dose of pituitary, left lens and right lens [(5.988 ± 3.299),( 2.258 ± 0.872),( 4.207 ± 3.303) mGy, r values were 0.766, 0.684, 0.727; P<0.01]. AK values was (31 ± 23) mGy and it had a relationship with pituitary absorption dose (r value was 0.894, P<0.01). The lens dose was reduced when the additional filtration was increased and the collection field was decreased, the radiation dose of the pituitary was reduced when both the additional filtration and the collection field were increased. Conclusions In the head and neck DSA examinations, the radiation dose of the lens and the pituitary had different changes with the different additional filters and collecting fields. The organ dose with 3D?DSA was significantly less than that with 2D?DSA.