Coronary artery stent evaluation

Discussion

Patient with cardiac disease, previous myocardial infarction located in the inferior and posterior wall.

Iodine no Water images highlighted the iodine uptake while reducing the metal artifacts of the stent. Stent lumen was also better evaluated.

Axial images, curved plane reformatted (CPR) images

Due to metal artifacts, conventional CCTA image was unable to show the in-stent situation clearly. However, monoenergetic 50 keV and Iodine no Water images could be used to evaluate the restenosis. Z effective images helped differentiate the components of the plaque. Monoenergetic 50 keV images also clearly showed the myocardium defect, which was obviously different from the normal tissue. Iodine no Water images showed the low iodine content.

Detection of stent restenosis is particularly important for coronary stent follow-up examination. Conventional images can be challenging to interpret due to metal artifacts. Therefore, an analysis with multiple spectral results (monoenergetic 50 keV, Iodine no Water, Z effective image) can be used to display the restenosis of the stent and can also show the myocardial ischemia of the endocardium and help to more accurately evaluate the status of the coronary arteries and myocardium

Image

Monoenergetic 150 keV image: CT value of contrast medium in the blood is decreased. The plaque visualization is therefore poor. However, the stent metal artifacts are reduced effectively, and the stent is displayed more clearly.

Monoenergetic 50 keV image: CT value of the contrast medium in the blood is increased, the contrast between plaque and contrast medium contained in the stent is improved. The plaque in the stent is shown clearly (arrow).

Image

Water

Highlights the contrast media, plaque in stent is clearly displayed (arrow).

Image

Stent, iodine, and plaque in stent were shown in different colors because of their different effective atomic numbers. Plaque in stent is demonstrated clearly (arrow).

All spectral images clearly showed subendocardial perfusion defect in the inferior wall of the myocardium.

History