Effect Of Contrast Mediume On The Three-dimensional Digital Subtraction Angiography Of Cerebral Vascular Image Quality

PART 1:Application study of low injection rate and lowcontrast medium volumes in three-dimensional rotationaldigital subtraction angiography of cerebral vascularObjective:To investigate the imaging quality and application value of low injection rate and low contrast medium volumes in three-dimensional rotational digital subtraction angiography of cerebral vascular.Methods : A total of 58 patients with suspected aneurysm or arteriovenous malformation who needed undergo 3D-DSA cerebral angiography were prospectively collected. And the patients were divided into three groups according to injection rate(Group A: 1.5ml/s, 20 cases; group B: 2ml/s, 21 cases; Group C: 3ml/s, 17 cases). Non-ionic iodinated contrast medium(Iopromide 370 mg I/100ml) was used in all the three groups. The catheter tip was kept within internal carotid artery at epistropheus level and Dyna CT 5s DSA imaging mode was used. Noise, signal-to-noise ratio(SNR) and contrast-to-noise ratio(CNR) of the petrous segment and the ophtalmic segment of the internal carotid artery(C2 segment and C6 segment), the M1 segment of the middle cerebral artery and the A1 segment of the anterior cerebral artery(M1 segment and A1 segment) were calculated in the axial image of C-arm cone-beam CT(C-arm CBCT). The original continuous subtraction images and reconstructed images(VR, MIP) were evaluated by two physicians. All data were analyzed statistically.Result: No significant differences were found about noise among three groups(P>0.05). Significant differences were found about SNR and CNR of M1 segment and A1 segment among Group A and Group B(P<0.05), but for C2 segment and C6 segment, it was not significant(P>0.05). Significant differences were found about SNR and CNR of all segments(C2 segment,C6 segment,M1 segment and A1 segment) among Group A and Group C(P<0.05). No significant differences were found about SNR and CNR of C6 segment and M1 segment among Group B and Group C(P>0.05), but for C2 segment and A1 segment, it was significant(P<0.05). No significant differences were found about scores of two physicians(P>0.05).Conclusion: 3D-DSA cerebral angiography with a personalized injection protocol of low injection rate and low contrast medium volumes was feasible. And the application of this protocol can reduce the dose of iodine and the risk of cerebral hemorrhage.PART 2:The imaging effect of different concentrationcontrast medium on three-dimensional digital subtractionangiography of cerebral vascularObjective: To explore the imaging effect of different concentration contrast medium in three-dimensional digital subtraction angiography(3D-DSA) of cerebral vascular.Methods: Patients with suspected aneurysms were continuously collected and divided into five groups randomly, group A:350 mg I/ml-3 ml/s; group B: 350 mg I/ml-4 ml/s; group C:400 mg I/ml-3 ml/s; group D:400 mg I/ml-4 ml/s; group E:270 mg I/ml-4 ml/s. The SNR and CNR of the C2 segment, the C6 segment, the M1 segment and the A1 segment were calculated in the axial image. The continuous subtraction images and reconstructed images(VR, MIP) were evaluated by two physicians respectively. The contrast medium dose and preoperative serum creatinine(Scr), postoperative 24 hours Scr, postoperative 48 hours Scr were recorded.Results: Significant differences were found about SNR and CNR between group A and group C(all P<0.05). Significant differences were found about SNR and CNR of C2 segment between group B and group D, group B and group E, group D and group E(all P<0.05), but for C6 segment,M1 segment and A1 segment, it was not significant(all P>0.05). No significant differences were found about SNR and CNR between group A and group B, group C and group D(all P > 0.05). No significant differences were found about scores of the continuous subtraction images, the VR images and MIP images between five groups(all P>0.05). No significant differences were found about the contrast medium dose and preoperative Scr, postoperative 24 hours increased Scr, postoperative 48 hours increased Scr of patients with different concentration contrast medium(all P>0.05).Conclusion: In 3D-DSA cerebral angiography, with a higher concentration, higher quality images can be obtained. There is no difference between iso-osmolar contrast agent and low-osmolar contrast agent for Scr value within postoperative 48 hours of patients.