title: CT Angiography: Post-processed Contrast Enhancement for Improved Detection of Pulmonary Embolism.
abstract: The study aimed to improve the detection of pulmonary embolism via an iodine contrast enhancement tool in patients who underwent suboptimal enhanced computed tomography angiography (CTA).
  
  
  
  We evaluated the CT examinations of 41 patients who underwent CTA for evaluation of the pulmonary arteries which suffered from suboptimal contrast enhancement. The contrast enhancement of the reconstructed images was increased via a post-processing tool (vContrast). Image noise and contrast-to-noise ratio (CNR) were assessed in eight different regions: main pulmonary artery, right and left pulmonary arteries, right and left segment arteries, muscle, subcutaneous fat, and bone. For subjective image assessment, three experienced radiologists evaluated the diagnostic quality.
  
  
  
  While employing the post-processing algorithm, the CNR for contrast-filled lumen and thrombus/muscle improves significantly by a factor of 1.7 (CNR without vContrast = 8.48 ± 6.79/CNR with vContrast = 14.46 ± 5.29) (P <0.01). No strengthening of artifacts occurred, and the mean Hounsfield unit values of the muscle, subcutaneous fat, and the bone showed no significant changes. Subjective image analysis illustrated a significant improvement using post-processing for clinically relevant criteria such as diagnostic confidence.
  
  
  
  vContrast makes CT angiograms with inadequate contrast applicable for diagnostic evaluation, offering an improved visualization of the pulmonary arteries. In addition, vContrast can help in the significant reduction of the iodine contrast material.
authors.affiliation: Department of Radiology, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany. Electronic address: muenzel@tum.de.
authors.forename: Daniela
authors.initials: D
authors.lastname: Muenzel
authors.affiliation: Department of Radiology, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany.
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Fingerle
authors.affiliation: Department of Radiology, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany.
authors.forename: Tina
authors.initials: T
authors.lastname: Zahel
authors.affiliation: Department of Radiology, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Sauter
authors.affiliation: CT Clinical Science, Philips HealthCare, Brussels, Belgium.
authors.forename: Alain
authors.initials: A
authors.lastname: Vlassenbroek
authors.affiliation: Department of Radiology, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Dobritz
authors.affiliation: Department of Radiology, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany.
authors.forename: Ernst J
authors.initials: EJ
authors.lastname: Rummeny
authors.affiliation: Department of Radiology, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany.
authors.forename: Peter B
authors.initials: PB
authors.lastname: Noël
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D016477:Artifacts; D001842:Bone and Bones / Q000000981:diagnostic imaging; D000072226:Computed Tomography Angiography / Q000379:methods*; D003287:Contrast Media; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging; D015588:Observer Variation; D011651:Pulmonary Artery / Q000000981:diagnostic imaging; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*
chemical_list: D003287:Contrast Media
keywords: Computed tomography; contrast enhancement; non-ionic iodine contrast agent; post-processing software; pulmonary embolism