title: The assessment of intracranial bleeding with virtual unenhanced imaging by means of dual-energy CT angiography.
abstract: The purpose of this study was to assess virtual unenhanced brain computed tomography (CT) images obtained by dual-energy CT angiography (CTA) for the detection of intracranial bleeding. In total, 25 patients were included in the study (average age 53.2 years, range 25-75 years, 14 male, 11 female), all with intracranial bleeding on unenhanced brain CT and who underwent additional CTA performed on a dual-source CT in a dual-energy acquisition mode. The two X-ray tubes were operated at 140 and 80 kV, respectively. Data were analyzed using dual-energy evaluation software. Virtual unenhanced images were calculated by removing the relative iodine content from each voxel. The virtual unenhanced images were evaluated by a radiologist blinded to the findings of the conventional images related to the presence of intracranial bleeding. The image quality and contrast-to-noise ratio (CNR) between bleeding and brain tissue were assessed. The virtual image quality was found to be sufficient in 96%. The agreement in detection of intracranial bleeding on virtual and conventional unenhanced images reached 96% in per-lesion analysis and 100% in per-patient analysis. The averaged CNR reached 2.63 in virtual unenhanced images and 3.27 in conventional. Virtual unenhanced images are sufficient for the detection of intracranial bleeding.
authors: Radiodiagnostic Clinic, Charles University Teaching Hospital Plzen, Alej Svobody 80, 30640, Plzen, Czech Republic. ferda@fnplzen.cz
authors: Jirí
authors: J
authors: Ferda
authors: Milan
authors: M
authors: Novák
authors: Hynek
authors: H
authors: Mírka
authors: Jan
authors: J
authors: Baxa
authors: Eva
authors: E
authors: Ferdová
authors: Alena
authors: A
authors: Bednárová
authors: Thomas
authors: T
authors: Flohr
authors: Bernhard
authors: B
authors: Schmidt
authors: Ernst
authors: E
authors: Klotz
authors: Boris
authors: B
authors: Kreuzberg
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000328:Adult; D000368:Aged; D002533:Cerebral Angiography / Q000379:methods*; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D020300:Intracranial Hemorrhages / Q000000981:diagnostic imaging*; D007455:Iodine; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014584:User-Computer Interface
chemical_list: D003287:Contrast Media; D007455:Iodine