Feasibility Of Low Tube Voltage, Low Concentration And Individual Contrast Medium Volume For Cerebral And Carotid CTA

Objective: To evaluate the feasibility of low tube voltage, low concentration and individual contrast medium volume for cerebral and carotid CTA with 256-slice spiral CT scanner.Methods: Totally 90 patients who underwent cerebral and carotid CTA were randomly divided into 3 groups which were divided by the voltage, concentration and volume of contrast medium(group A: 100 Kv, 300 mg I/m L, 60 m L; group B: 100 k V,300 mg I/m L, individual volume; group C: 120 k V, 370 mg I/m L, 60 m L).The CT value,image quality,Artifact of subclavian vein, the degree of vein contamination and radiation dose were compared in 3 groups. The volume of contrast medium was compared between group A and B.Results: ①There were statistical differences among 3 groups in CT value of some arteries(P<0.05), which were higher in group A and B than in group C. ②There were statistical differences among 3 groups in SNR and CNR value of some plane(P < 0.05), which were lower in group A and B than in group C. ③ There was no significant difference in the image quality of all arteries except for the right subclavian artery among 3 groups. ④The Artifact of subclavian vein grade was highest in group B,and there was no statistical differences in the degree of vein contamination. ⑤ The radiation dose was significantly higher in group A and B than in group C(P <0.05).There was no statistical difference between group A and B(P>0.05). ⑥The volume of contrast medium in group B was declined in those patients, weighing between 45 kg and60kg and between 61 kg and 75 kg. which was ascended in those patients, weighing more than 75 kg. there was no statistical difference in the average volume of contrast medium between group A and B(P>0.05).Conclusion: It can reduce the radiation dose and the damage of contrast medium, using low tube voltage, low concentration and individual contrast medium for cerebral and carotid CTA with 256-slice CT.