Impact of an advanced image-based monoenergetic reconstruction algorithm on coronary stent visualization using third generation dual-source dual-energy CT: a phantom study

Abstract

To evaluate the impact of an advanced monoenergetic (ME) reconstruction algorithm on CT coronary stent imaging in a phantom model. Three stents with lumen diameters of 2.25, 3.0 and 3.5mm were examined with a third-generation dual-source dual-energy CT (DECT). Tube potential was set at 90/Sn150kV for DE and 70, 90 or 120kV for single-energy (SE) acquisitions and advanced modelled iterative reconstruction was used. Overall, 23 reconstructions were evaluated for each stent including three SE acquisitions and ten advanced and standard ME images with virtual photon energies from 40 to 130keV, respectively. In-stent luminal diameter was measured and compared to nominal lumen diameter to determine stent lumen visibility. Contrast-to-noise ratio was calculated. Advanced ME reconstructions substantially increased lumen visibility in comparison to SE for stents ≤3mm. 130keV images produced the best mean lumen visibility: 86% for the 2.25mm stent (82% for standard ME and 64% for SE) and 82% for the 3.0mm stent (77% for standard ME and 69% for SE). Mean DLP for SE 120kV and DE acquisitions were 114.4 ± 9.8 and 58.9 ± 2.2mGy × cm, respectively. DECT with advanced ME reconstructions improves the in-lumen visibility of small stents in comparison with standard ME and SE imaging. • An advanced image-based monoenergetic reconstruction algorithm improves lumen visualization in stents ≤3.0mm. • Application of high keV reconstructions significantly improves in-stent lumen visualization. • DECT acquisition resulted in49 % radiation dose reduction compared with 120kV SE.