Detecting intimal hyperplasia of subclavian artery stent by multislice computed tomography

A 62-year-old man was performed stent implantation for right subclavian artery stenosis two years ago. For the evaluation of stent patency, multislice computed tomography (MSCT) was performed. Volume rendering image demonstrated that the stent was patent, but curved multiplanar reformation revealed a relatively low- density area inside the stent, suggesting intimal hyperplasia. Cross-sectional images were converted into Plaque Map display, which color-codes CT densities. Plaque was eccentrically distributed from ten oʹclock to four oʹclock. The attenuation of the plaque was 250--350 HU, which was less than the attenuation of contrast media (350--500 HU). Invasive aortography demonstrated the stent to be mildly stenosed in the corresponding position. Gray-scale and VH (virtual histology)-intravascular ultrasound demonstrated that eccentric intimal thickening consisted with predominant fibrous plaque. MSCT combined with Plaque Map effectively detected intimal thickening of subclavian artery stent.