Stent imaging on a clinical dual-source photon-counting detector CT system-impact of luminal attenuation and sharp kernels on lumen visibility

Decker, Josua A. A.; O'Doherty, Jim; Schoepf, U. Joseph; Todoran, Thomas M. M.; Aquino, Gilberto J. J.; Brandt, Verena; Baruah, Dhiraj; Fink, Nicola; Zsarnoczay, Emese; Flohr, Thomas; Schmidt, Bernhard; Allmendinger, Thomas; Risch, Franka; Varga-Szemes, Akos und Emrich, Tilman (2022): Stent imaging on a clinical dual-source photon-counting detector CT system-impact of luminal attenuation and sharp kernels on lumen visibility. In: European Radiology, Bd. 33, Nr. 4: S. 2469-2477

Abstract

Objectives To assess the impact of scan modes and reconstruction kernels using a novel dual-source photon-counting detector CT (PCD-CT) on lumen visibility and sharpness of different stent sizes. Methods A phantom containing six balloon-expandable stents (2.5 to 9 mm diameter) in silicone tubing was scanned on a PCD-CT with standard (0.6 mm and 0.4 mm thicknesses) and ultra-high-resolution (0.2 mm thickness) modes. With the use of increasing contrast medium concentrations, densities of 0, 200, 400, and 600 HU were achieved. Standard-resolution scans were reconstructed using increasing sharpness kernels, using both polyenergetic quantitative soft tissue conventional ((Qr40(c)(0.6 mm), Qr40(c)(0.4 mm), Qr72(c)(0.2 mm)) and vascular (Bv) virtual monoenergetic reconstructions (Bv44(m)(0.4 mm), Bv60(m)(0.4 mm)) at 70 keV. In-stent lumen visibility, sharpness (max. delta HU of the stent measured in profile plots), and in-stent noise (standard deviation of HU) were measured. Results In-stent lumen visibility was highest for Qr72(c)(0.2 mm) (86.5 +/- 2.8% to 88.3 +/- 2.6%) and in Bv60(m)(0.4 mm) reconstructions (77.3 +/- 2.9 to 82.7 +/- 2.5%). Lumen visibility was lowest in the smallest stent (2.5 mm) ranging from 54.1% in Qr40(c)(0.6 mm) to 74.1% in Qr72(c)(0.2 mm) and highest in the largest stent (9 mm) ranging from 93.8% in Qr40c(0.6 mm) to 99.1% in the Qr72(c)(0.2 mm) series. Lumen visibility decreased by 2.1% for every 200-HU increase in lumen attenuation. Max. delta HU between stents and stent lumen was highest in Qr72(c)(0.2 mm) (delta HU 892 +/- 504 to 1526 +/- 517) and Bv60(m)(0.4 mm) series (delta HU 480 +/- 357 to 1030 +/- 344). Improvement of lumen visibility and sharpness in UHR and Bv60(m)(0.4 mm) series was strongest in smaller stent sizes. Conclusion UHR acquisition mode and sharp reconstruction kernels on a novel PCD-CT system significantly improve in-stent lumen visibility and sharpness-especially for smaller stent sizes.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0938-7994
• Sprache: Englisch