Computed tomography pulmonary angiograms using a novel dual-layer spectral detector: Adjusted window settings are essential for diagnostic image quality. Issue 33 (August 2019)

• Record Type: Journal Article
• Authors: Iuga, Andra-Iza; Doerner, Jonas; Siedek, Florian; Haneder, Stefan; Byrtus, Jonathan; Luetkens, Julian A.; Maintz, David; Hickethier, Tilman
• Other Names: Chen. Robert section editor.
• Is Part Of: Medicine. Volume 98:Issue 33(2019)
• Publication Date: 2019-08
• Subjects: dual-energy CT -- pulmonary angiography -- spectral detector CT -- virtual monoenergetic imaging -- window settings; Medicine -- Periodicals; Medicine -- Periodicals; Médecine -- Périodiques; Geneeskunde; Medicine; Periodicals; Periodicals; 610.5
• DOI: 10.1097/MD.0000000000016606
• Languages: English
• ISSNs: 0025-7974

Abstract

Abstract: Objective: The aim of this study was to determine optimal window settings for conventional polyenergetic and virtual monoenergetic images derived from computed tomography pulmonary angiogram (CTPA) examinations of a novel dual-layer spectral detector computed tomography system (DLCT). Methods: Monoenergetic (40 keV) and polyenergetic images of 50 CTPA examinations were calculated and the best individual window width and level (W/L) values were manually assessed. Optimized values were obtained afterwards based on regression analysis. Diameters of standardized pulmonary artery segments and subjective image quality parameters were evaluated and compared. Results: Attenuation and contrast-to-noise values were higher in monoenergetic than in polyenergetic images ( P ⩽.001). Averaged best individual W/L for polyenergetic and monoenergetic were 1020/170 and 2070/480 HU, respectively. All adjusted W/L-settings varied significantly compared to standard settings (700/100 HU) and obtained higher subjective image quality scores. A systematic overestimation of artery diameters for standard window settings in monoenergetic images was observed. Conclusions: Appropriate W/L-settings are required to assess polyenergetic and monoenergetic CTPA images of a novel DLCT. W/L-settings of 1020/170 HU and 2070/480 HU were found to be the best averaged values for polyenergetic and monoenergetic CTPA images, respectively.