Yanhai Cui MA, Presenter: Nothing to Disclose

Changhong Liang MD, Abstract Co-Author: Nothing to Disclose

Hui Liu MD, Abstract Co-Author: Nothing to Disclose

Ying Guo, Abstract Co-Author: Nothing to Disclose

Li Xu MA, Abstract Co-Author: Nothing to Disclose

To research the influence of contrast media concentration in displaying the extent of stenosis due to non-calcified plaque.

Five coronary artery models containing -150Hu and 100Hu CT value plaques, respectively, was scanned at 64 MDCT. Each model had lumina stenosis of 75%, 50%, 25%, respectively. Twelve different concentration contrast media was filled in the five model catheters in order. The scan protocol is 0.35s/r, 0.2pitch, 120kV, 600mA. CT value of the contrast media were measured, the extent of stenosis was measured by vessel analysis software of GE workstation4.2. t-test was used for statistical analysis. p<0.05 is significant.

The range of CT value of contrast media was from 208Hu to 780Hu. The mean percent of measured stenosis were 63.33%±7.83％, 40.75%±7.90％, 18.00%±7.13％ for true 75%, 50%, 25% stenosis, respectively, in groups of CT value of contrast media ≤310Hu, those were 56.84±7.01％, 36.09%±5.43％, 17.72%±7.08％ in groups of CT value of contrast media ＞310Hu. The differences of percent of measured stenosis for 75% and 50% stenosis between two groups was significant (stenosis75%: t=2.651, p=0.011; stenosis50%: t=2.229, p=0.031). There was no significant difference between two groups for 25% stenosis (p＞0.05).

There is an underestimate in assessing non-calcified stenosis,which is relative to the level of enhancement.About 310Hu CT value enhancement level is more accurate in assessing coronary artery non-calcified plaque stenosis than higher enhancement , however, it still results in about 10% underestimate.

This test tells us what enhancement level is favorable in coronary artery CTA.

Cui, Y, Liang, C, Liu, H, Guo, Y, Xu, L, Is There Any Difference in Contouring Coronary Artery Non-calcified Plaque with Various Concentration Contrast Media at Coronary Computed Tomographic Angiography (CTA) Using 64-MDCT.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5014456.html