Utility of the digital angiography method that gave the dynamic density optimization processing in the abdominal angiography

Congress:

ECR 2018

Poster Number:

C-1810

Type:

Scientific Exhibit

Keywords:

Arthrography, Catheter arteriography, Interventional vascular, Image verification

Authors:

T. Iwamoto, S. Yuda, T. Sakamot, H. Takeuchi, J. Shudo, A. Nakanishi; Mitaka/JP

DOI:

10.1594/ecr2018/C-1810

DOI-Link:

https://dx.doi.org/10.1594/ecr2018/C-1810

Fig. 11: Bar graphs of the gray values at different DDO values. Blue bar graphs...

Table 1: Mean gray values and their SD in the lung, soft tissue, and bone at different...

Fig. 12: Profile curves for our 2-mm diameter vessel phantom at different contrast...

Fig. 13: Profile curves for our 5-mm diameter vessel phantom at different contrast...

Fig. 14: Strength of halo effect at different contrast medium concentrations. Red line...

Table 2: Strength of halo effect at different vessel opacities and diameters

Fig. 15: Vessel phantom images of 2-mm diameter at different contrast medium...

Fig. 16: Vessel phantom images of 5-mm diameter at different contrast medium...

Fig. 17: Bar graphs of vessel visibility at different contrast medium concentrations....

Fig. 18: Vessel phantom images of 2-mm diameter with superimposed bone phantom at...

Fig. 19: Vessel phantom images of 5-mm diameter with superimposed bone phantom at...

Fig. 20: Bar graphs of vessel visibility with superimposed bone phantom at different...

Fig. 21: Comparison of vessel contrast for 2-mm diameter phantom between DA (DDO value...

Fig. 22: Comparison of vessel contrast for 5-mm diameter phantom between DA (DDO value...

Table 3: Comparison of vessel contrast between DA (DDO value at 90%) and DSA at...

Results

1. Image quality assessment at different DDO values

With the DDO value at 60% or lower, the gray value in the lung was twice or more as high as that in the bone and halation artifacts appeared significant (Figures 5 and 11, Tables 1). As the DDO value increased, the image contrast among the lung, soft tissue, and bone was decreased (Figures 5 and 11, Tables 1). Particularly, the image contrast was almost lost at the DDO value at 100%. Thus, the image contrast was preserved to some extent without significant halation artifacts with the DDO value at 70% to 90%.

2. Halo effect at different vessel opacities and diameters

Figures 12 and 13 show the profile curves generated with various iodine concentrations for the vessel phantom with the lumen diameter of 2 and 5 mm, respectively. For both the phantoms, the strength of halo effect was increased as the iodine concentrations increased or the dilution ratio decreased (Figures 12-14, Tables 2). The strength of halo effect was higher for the 5-mm diameter phantom than for the 2-mm diameter phantom at each iodine concentration.

3. Vessel visibility at different vessel opacities and diameters

The average of the vessel visibility grades without the bone phantom was 3 or higher (i.e., appropriate) for the 2-mm diameter phantom filled with iodine contrast medium of 7-or-less-time dilution ratio and for the 5-mm diameter phantom, 10-or-less-time dilution ratio (Figure 15-17). Similarly, the average of the grades with the bone phantom was 3 or higher for both the 2- and 5-mm diameter phantoms filled with contrast medium of 5-or-less-time dilution ratio (Figure 18-20).

4. Vessel contrast comparison between DA and DSA at different vessel opacities and diameters

For the 2-mm diameter vessel phantom, the vessel contrast by DA (DDO value at 90%) when filled with the original iodine contrast medium was higher than that by DSA when filled with contrast medium of 2-or-more-time dilution ratio (Figure 21, Table 3). The vessel contrast by DA was approximately 60% of that by DSA when filled with the original contrast medium. On the other hand, for the 5-mm diameter vessel phantom, the vessel contrast by DA when filled with the original contrast medium was higher than that by DSA when filled with contrast medium of 3-or-more-time dilution ratio (Figure 22, Table 3). The vessel contrast by DA was approximately 40% of that by DSA when filled with the original contrast medium.