title: Can dual-energy CT improve the assessment of tumor margins in oral cancer?
abstract: OBJECTIVE
  The aim was to investigate the image quality of dual-energy computed-tomography (DECT) compared to single-energy images at 80 kV and 140 kV in oral tumors.
  
  
  METHODS
  Forty patients underwent a contrast-enhanced DECT scan on a definition flash-CT. Four reconstructions (80 kV, 140 kV, mixed (M), and optimum-contrast (OC)) were assessed by four blinded readers for subjective image quality (10-point scale/10=best). For objective quality assessment, linear attenuation measurements (line density profiles (LDP)) were positioned at the tumor margin, and the difference between minimum and maximum was calculated. Signal-to-noise ratios (SNR) were measured in the tongue.
  
  
  RESULTS
  The mean image quality for all readers was 5.1±0.3, 8.4±0.3, 8.1±0.2, and 8.3±0.2 for the 140 kV, 80 kV, M, and OC, respectively (P<001 between 140 kV and all others). The mean difference between the minimum and maximum within the LDP was 139.4±59.0, 65.7±29.5, 105.1±46.5, and 118.7±59.4 for the 80 kV, 140 kV, M, and OC, respectively (P<001). The SNR for the tongue was 3.8±2.1, 3.8±2.1, 4.2±2.4, and 4.1±2.3 for the 80 kV, 140 kV, M, and OC, respectively.
  
  
  CONCLUSIONS
  DECT of oral tumors offers high image quality, with subjectively rated image quality and attenuation contrast at the tumor margin similar to that of 80 kV; DECT, however, provides a significantly higher SNR compared to 80 kV.
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, University Hospital of Vienna, Medical University of Vienna, Austria. Electronic address: michael.toepker@meduniwien.ac.at.
authors.forename: Michael
authors.initials: M
authors.lastname: Toepker
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, University Hospital of Vienna, Medical University of Vienna, Austria. Electronic address: christian.czerny@meduniwien.ac.at.
authors.forename: Christian
authors.initials: C
authors.lastname: Czerny
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, University Hospital of Vienna, Medical University of Vienna, Austria. Electronic address: helmit.ringl@meduniwien.ac.at.
authors.forename: Helmut
authors.initials: H
authors.lastname: Ringl
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, University Hospital of Vienna, Medical University of Vienna, Austria. Electronic address: julia.fruehwald-pallamar@meduniwien.ac.at.
authors.forename: Julia
authors.initials: J
authors.lastname: Fruehwald-Pallamar
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, University Hospital of Vienna, Medical University of Vienna, Austria. Electronic address: florian.wolf@meduniwien.ac.at.
authors.forename: Florian
authors.initials: F
authors.lastname: Wolf
authors.affiliation: Department of Biomedical Imaging and Image-guided Therapy, University Hospital of Vienna, Medical University of Vienna, Austria. Electronic address: michael.weber@meduniwien.ac.at.
authors.forename: Michael
authors.initials: M
authors.lastname: Weber
authors.affiliation: University Clinic of Craniomaxillofacial and Oral Surgery, Medical University of Vienna, Austria; Department for Oral and Maxillofacial Surgery, Feldkirch Hospital, Feldkirch, Austria. Electronic address: oliver.ploder@lkhf.at.
authors.forename: Oliver
authors.initials: O
authors.lastname: Ploder
authors.affiliation: University Clinic of Craniomaxillofacial and Oral Surgery, Medical University of Vienna, Austria. Electronic address: clemens.klug@meduniwien.ac.at.
authors.forename: Clemens
authors.initials: C
authors.lastname: Klug
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging*; D018289:Carcinoma, Verrucous / Q000000981:diagnostic imaging*; D003287:Contrast Media; D003793:Dental Restoration, Permanent / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000000981:diagnostic imaging*; D011856:Radiographic Image Enhancement / Q000379:methods*; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: Dual energy; Image quality; Multidetector computed tomography; Oral cancer; Tumor margin