title: 128-slice acceletated-pitch dual energy CT angiography of the head and neck: comparison of different low contrast medium volumes.
abstract: BACKGROUND
  Our study aims to evaluate the image quality and feasibility of 128-slice dual-energy CTA (DE-CTA) for supra-aortic arteries using reduced amounts of contrast medium (CM).
  
  
  METHODS
  A prospective study was performed in 54 patients receiving CTA of the head and neck with a 128-slice dual-source CT system. Patients were randomized into two groups with a volume of either 40 mL of CM (Group I) or 50 mL of CM (Group II). Arterial and venous enhancements were recorded for quantitative assessment. Qualitative assessments for images without bone removal (BR) were based on a) the visualization of the circle of Willis and b) streak artifacts due to residual CM in the subclavian or internal jugular veins ipsilateral to injection of CM. Qualitative assessment of dual-energy images using BR was based on the presence of bone remnants and vessel integrity. Quantitative data was compared using the Student t test. The χ(2) test was used for the qualitative measurements of streak artifacts in veins while the Mann-Whitney U test was used for the qualitative measurements of images with BR.
  
  
  RESULTS
  Arterial and venous attenuation was significantly higher in Group II (P=0.000). Image quality regarding the circle of Willis was excellent in both groups (3.90±0.30 for Group I and 4.00±0 for Group II) . Imaging of the internal jugular veins was scored higher in Group I (1.87±0.72) compared with Group II (1.48±0.51) (P=0.021). Within Group I using BR, mean scores for bone remnants did not differ significantly (P>0.05) but mean scores of vessel integrity (P<0.05) did.
  
  
  CONCLUSIONS
  Contrast-enhanced head and neck CTA is feasible using a scan protocol with low amounts of contrast medium (40 mL) on a 128-slice dual-energy CTA. The 40-mL protocol provides satisfactory image quality before and after dual-energy bone-removal post-processing.
authors.affiliation: Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.forename: Huadan
authors.initials: H
authors.lastname: Xue
authors.forename: Zheng-yu
authors.initials: ZY
authors.lastname: Jin
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Hao
authors.initials: H
authors.lastname: Sun
authors.forename: Xuan
authors.initials: X
authors.lastname: Wang
authors.forename: Zhu-hua
authors.initials: ZH
authors.lastname: Zhang
authors.forename: Da-ming
authors.initials: DM
authors.lastname: Zhang
authors.forename: Guang-ming
authors.initials: GM
authors.lastname: Lu
authors.forename: Zhao-qi
authors.initials: ZQ
authors.lastname: Zhang
authors.forename: U Joseph
authors.initials: UJ
authors.lastname: Schoepf
authors.forename: Andreas M
authors.initials: AM
authors.lastname: Bucher
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Wolla
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction / Q000379:methods; D050197:Atherosclerosis / Q000175:diagnosis / Q000000981:diagnostic imaging*; D001842:Bone and Bones / Q000000981:diagnostic imaging; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006257:Head / Q000098:blood supply / Q000000981:diagnostic imaging*; D006801:Humans; D007472:Iohexol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D007601:Jugular Veins / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000098:blood supply / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide