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Objective To compare radiation doses to patients between rotational angiography and standard angiography.Methods According to different modes,our experiment was divided into RA (Dual-axis Rotational Angiography) group and SA (Standard Angiography) group.The latter was divided into 3 subgroups (SA1,SA2 and SA3) in terms of different time of cine.The procedure time and the position were controlled by the order preset into the machine.Each group consisted of 10 repeated operations with a unique phantom to simulate the true patients.The radiation doses were measured by using dose meter provided by the machine and TLD system; the means of the data were compared.Results The mean of total accumulated DAP and AK in group RA were 3 061.6 mGy·cm2 and 64.2 mGy,respectively,compared with group SA1 (4 213.9 mGy·cm2 and 85.5 mGy),SA2 (6 436.0 mGy·cm2 and 112.2 mGy),SA3 (12 810.4 mGy·cm2 and 243.7 mGy).The mean of accumulated dose in group RA was 37.70 mGy,higher than group SA1 (26.56 mGy) but lower than group SA2 (46.86 mGy) and SA3 (77.79 mGy).The gap between highest dose and lowest dose in RA group was insignificant whereas significant in the subgroups of SA.Conclusions In comparison with conventional angiography,the dual-axis rotational angiography has the potential to reduce radiation exposure of patients significantly so as to prevent skin radiation injures.
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Objective To observe the clinical safety of dual axis rotational coronary angiography (DARCA) in the diagnosis of coronary artery disease in Chinese population.Methods From March to December in 2010,74 patients undergoing diagnostic DARCA were enrolled.The improved isocentering technique was adopted in 34 of the patients at the end of the study during DARCA.Blood pressure,heart rate and symptoms were recorded immediately before-and-after contrast injections.Contrast dose,radiation exposure and procedure time for DARCA were recorded.Continuous variable data were analyzed using Student＇s t test,if normality assumption was violated,rank sum test would be used.Categorical variables were analyzed using x2 test.Results ( 1 ) Clinical safety:There was no chest pain documented during or immediately post-injection for all patients.Only 1 patient ( 1 ％ ) had an attack of ventricular tachycardia immediately after the contrast injection and then relieved automatically.Pre and post-injection systolic blood pressure values of left coronary artery were statistically different [ ( 116 ± 20 ) mm Hg vs.( 111 + 18) mm Hg( 1 mm Hg =0.133 kPa),t =3.303,P =0.001 ],and heart rates differed,too [ 73 ( 65- 84)bpm vs.71(64-78) bpm,Z =-4.789,P =0.001 ],but that imposed no clinical significance.(2)Contrast dose,radiation dose and procedure time:The mean contrast utilization,radiation dose and procedure time for DARCA were 28 (25-34) ml,8979 ( 6733-12 363 ) mGycm2 and 200 (164-270) s.Compared with conventional DARCA,improved isocentering technique during DARCA had less radiation exposure and procedure time in left coronary artery angiography and the whole coronary artery angiography [ left coronary artery angiographic radiation exposure:4004 (2932-5772) mGycm2 vs.5808 (4798- 8838) mGycm2,Z =-3.471,P =0.001 ;total radiation exposure:(8116 +2493) mGycm2 vs.( 11 371 ±4122) mGycm2,t =-4.176,P =0.001 ; left coronary artery angiographic procedure time:120 ( 80-180)s vs.150(126-214) s,Z =- 2.836,P =0.005; total procedure time:180 (139-240) s vs.220( 186-308 )s,Z =-3.004,P =0.003 ],but there was no statistically difference in contrast utilization [30(25-35) ml vs.27(25-34)ml,Z=-0.906,P=0.365].Conclusion This study demonstrates clinical safety of DARCA in the diagnosis of coronary artery disease in Chinese population.Compared with conventional isocentering technique of DARCA,improved isocentering technique can significantly reduce radiation exposure and procedure time on the basis of simplified operation,and replace the conventional isocentering technique,but randomized double-blind controlled studies should be conducted.
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Objective To investigate the pathologic foundation,clinical characteristics and CT features of microscopic polyangiitis(MPA)with lung involvement.Methods Clinical data of 6 patients of MPA with lung involvement in 2003-2006 were retrospectively analyzed.Results The types of lung imaging manifestations as the followings:(1)Mutiple flaky shadow in both lung in 3 cases.(2)Ground-glass shadow in 1 case.(3)Disseminated interstitial lung involvement in 2 cases.The main respiratory symptom was haemoptysis except cough and expectoration.Renal damaging often occurred besides the lung.Six cases with positive antineutrophil cytoplasmic antibody(ANCA)and 5 cases with positive P-ANCA/MPO-ANCA were found in laboratory examination.Conclusions The CT manifestations of MPA with lung involvement have no characteristic features.Clinical characteristics and laboratory examination can help to understand and diagnose MPA with lung involvement early.