Abstract 2411: Usefulness of Deblurring (High-Contrast Enhancement) for Detecting Coronary Stents in Multislice Helical CT
Purpose High-speed MSCT with a larger number of detector rows has made coronary CTA clinically useful. However, blooming artifact around high-contrast objects such as stents in the coronary arteries impairs depiction of the coronary artery lumen and interferes with diagnosis. Therefore, we have developed a new Deblurring algorithm for high-contrast objects which uses the transfer function of the X-ray CT system. with Toshiba company.
Method and Materials The developed Deblurring involves deconvolution of the CT transfer function (modulation transfer function). This is equivalent to the convolution of inverse function of CT transfer function into blurred image. CT transfer function was obtained by 2D Fourier transformation of piano wire image. Deblurring was performed for 14 lesions in 11 patients (10 male, 1 female, mean age 66.4 ± 9.6 years old). The images before and after Deblurring were assessed based on visual evaluation by two observers, and the 5 grades scoring was classfied (Score 1: impossible of use. 2: worse. 3: not change. 4: good. 5: excellent).
Result A t-test comparison showed statistically significant differences between the two data sets with an average score of 4.4 (p<0.05). The use of new Deblurring algorithm improves the visualization of stented with statistical significance.
Conclusion Deblurring using the CT transfer function eliminates blurring caused by high-contrast objects. This function permits evaluation of in-stent restenosis, and that were previously considered impossible. Deblurring is expected to further improve the diagnostic capabilities and clinical usefulness of coronary CTA.