Evaluation of image quality for stent image with different dilution ratio of contrast agent in self-production vessel model on angiographic X-ray computed tomography (CT)

Nowadays, the interest and the number of examination of cerebral angiography and interventional procedure have been significantly increasing. In stent procedure on patients, the important point is to check especially whether the position of stent is complete. Also, the dilution ratio of contrast agent and normal saline (N/S) causes affect the quality of image. Thus, the purpose of this study was to find optimized dilution ratio of contrast agent for acquiring the high quality image with various diameters of self-production vessel model in AAPM head phantom. To evaluate the quality of image, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were used as a factor of quantitative measurement, and Likert scale was used as a factor of qualitative measurement. According to the results, we can acquire excellent result for 1:4 (contrast agent: N/S), 1:5, and 1:5 dilution ratios using 2, 3, and 5mm vessel diameters, respectively. In addition, quantitative measurement and qualitative measurement came up with same tendency. In conclusion, our results demonstrated that the 1:4 and 1:5 dilution ratio of contrast agent had outstanding results in 2, 3, and 5mm diameters of vessel model in phantom.