Fajin Lv MD, Presenter: Nothing to Disclose

Tianyou Luo, Abstract Co-Author: Nothing to Disclose

Jingmin Liao, Abstract Co-Author: Nothing to Disclose

Yun Shen PhD, Abstract Co-Author: Employee, General Electric Company

Zhiwei Zhang, Abstract Co-Author: Nothing to Disclose

Ken Chen, Abstract Co-Author: Nothing to Disclose

To introduce the advanced synchronous dual energy bone removal technique in Volume CT Digital Subtraction Angiography (VCTDSA) and to compare the post processing time and the image quality of cerebral vessel imaging with bone removal between VCTDSA and conventional CTA.

32 patients with cerebral vascular diseases underwent non-enhanced helical scan (80kV) and contrast-enhanced helical scan (120kV) at the same region with a 64 MDCT (GE, LightSpeed VCT). Optimized scan protocol and delay time between two scans were used to achieve the synchronous condition. The contrast-enhanced series was used for conventional CTA and the two series were used for VCTDSA. Cerebral vessels without bony structure were reformatted and displayed with 3D volume rendering (3D VR) and 3D maximum intensity projection (3D MIP). The post-processing time and the image quality were then compared (3 grade score method, 3: excellent, 2: good, 1: poor).

The image quality, especially the cerebral vessel without bony structure using VCTDSA was excellent (100%). Compared with conventional CTA, VCTDSA had advantages in displaying the whole intracranial arteries and veins and in reducing the interference of residual bony structure（р<0.001）. The post-processing time consumed by VCTDSA (6.87±2.96 min) was much shorter than that of conventional CTA (14.37±1.66 min, р<0.001). There was a significant positive correlation between the post-processing time and the image quality with VCTDSA ( r=0.79，p<0.001).

The post-processing of bone removal is very time consuming. Compared with the conventional CTA, VCTDSA needs much shorter post-processing time and could remove all the bony structure easily to display the whole cerebral vessels vividly. Synchronization between two scans and dual energy technique are very important factors in improving subtracted image quality.

VCTDSA could be applied as a routine diagnostic method for evaluating cerebral vessels.

Lv, F, Luo, T, Liao, J, Shen, Y, Zhang, Z, Chen, K, Advanced Synchronous Dual Energy Bone Removal Technique for Cerebral Vessel Imaging with 64 Row Multi-Detector Helical CT: Comparison between Volume CT DSA and Conventional CTA.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5004834.html