The research of influence of different additional filtration to image quality and radiation dose in the whole brain DSA

Objective: To investigate the effect of different additional filtration thickness of DSA on image quality and radiation dose with cerebral angiography. Methods: Prospective collected 90 patients with DSA examination of the whole cerebral artery, patients were divided into A, B and C group according to the time of the examination, each group included 30 cases. Patients underwent conventional DSA, the additional filtration of group A, B and C were (1.0 mmAl + 0.1 mmCu), (1.0 mmAl + 0.4 mmCu) and (1.0 mmAl + 0.9 mmCu), respectively. Dose area product (DAP), air kerma (AK), tube current and tube voltage of anteroposterior and lateral radiography of the whole brain were recorded, and scored the image quality. Eye lens organ dose values were obtained by using simulation phantom and LiF dosemeter under A, B and C groups with three different additional filtrations for cerebral angiography. The image quality scores and the radiation dose were analyzed by one-way ANOVA tests or Kruskal-Wallis tests. Results: The image quality comprehensive score of three groups showed significant difference (F = 40.07, P < 0.01), which were (3.8 ± 0.4), (3.6 ± 0.5) and (3.0 ± 0.6), respectively. The DAP and AK value of anteroposterior and lateral radiography of three groups also showed significant difference (P < 0.05), B and C group were lower than the A group. Left and right eye lens organ dose were decreased along with the increase of the additional filtration thickness, and the difference between the 3 groups also had significant difference (P < 0.01). Conclusion: Both the image quality and radiation dose can acquire when conducted the whole brain DSA with 1.0 mmAl + 0.4 mmCu additional filtration. (authors)