Objective To carry out further analysis and assessment of the radiation risk from DSA examinations and related factors.Methods All the online radiation dose values and associated parameters of the 107 patients examined were collected for purpose of statistical analyses according to their classification.Results The analyses of DSA examinations indicated:for coronary angiography,DAP was (22 285.5±18 682.7)μGy·m2,ESD was (2 942.1 ±2 557.3) mGy;for head angiography,DAP (25 929.6±8 302.7) μGy·m2,ESD (1 288.8 ±682.3) mGy;for abdominal angiography,DAP (12 129.7 ± 10 646.1) μGy· m2,ESD (730.1 ± 584.7) mGy.Conclusions Among total accumulated radiation dose,the dose arising form coronary angiography is the highest,followed by the head angiography,and the dose from abdominal angiography is the lowest.

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.

Objective:To explore the feasibility of long board detector of digital radiography(DR)in clinical application.Methods:The long board detector(detector)was erected and placed upright.The scale long ruler with marked metal lead wire was placed at 20 cm in front of the center of long axis of the board of detector,which paralleled medial axis.Three test cards of spatial resolution were respectively placed at three positions(upper,middle and lower)of detector,and they were stuck on the board of detector as 30cm intervals between each other and 45° position.The exposures were conducted at 100,150,and 200 cm of source image distance(SID).The incident doses were tested,which obtained from different SID spots of upper,middle and lower positions of detector.The spatial resolutions of 3 positions were determined through observed the images of cards.The ratio of the marked scale length with metal lead wire to actual length of lead wire was measured through the projection of the scale length,so as to obtain the amplification rate of different spot positions.The spatial distribution of effective focal plane on the direction of long axis of detector,and the morphological change of that were observed.Results:When SID spots were respectively 100,150 and 200cm,the amplification rates of images decreased with increasing SID.The difference of amplification rates among three SID spots was significant(F=223.80,P<0.001).There was significant difference in the corresponding radiation doses among different SID spots(F=7.57,P<0.05).The spatial resolution was constantly 1.8 LP/mm.There was heel effect along with the direction of short axis of detector.The effective focal spot on the direction of long axis of detector appeared up-down symmetrical display.Conclusion:The long board detector of DR equipment has realized the capture for the images of the overall length of spine or the overall length of lower limbs in one exposure,which can meet the clinical requirement,and improve the detection efficiency of X-ray.