title: Thoracoabdominal-aortoiliac MDCT angiography using reduced dose of contrast material.
abstract: OBJECTIVE
  The objective of our study was to compare the image quality of MDCT angiography studies obtained by injection of low doses of contrast medium with saline flush versus conventional doses of contrast medium.
  
  
  METHODS
  Seventy-one patients with pre- or postoperative aortic aneurysms underwent MDCT angiography throughout the thoracoabdominal-aortoiliac system using an 8-MDCT scanner. In 37 patients, 100 mL of contrast medium was injected at a flow rate of 3.0 mL/s (hereafter referred to as the 100-mL group). In 34 patients, 50 mL of contrast medium followed by a 20-mL saline flush was injected at a flow rate of 2.5 mL/s (the 50-mL group). For each group, quantitative analysis involved calculating the mean aortoiliac enhancement, plateau deviation, and contrast enhancement in the pulmonary trunk and superior vena cava (SVC). Qualitative analysis involved assessing the 3D postprocessing images.
  
  
  RESULTS
  Significant differences between the groups in mean aortoiliac enhancement (100-mL group vs 50-mL group, 337 +/- 6 H vs 319 +/- 5 H, p < 0.0001) and mean plateau deviation (51 +/- 4 H vs 58 +/- 4 H, p < 0.0001) were found. However, adequate arterial enhancement (>or= 200 H) was observed in 31 of 34 patients in the 50-mL group and uniform aortoiliac enhancement (< 50 H) was seen in 26 patients. Visual analysis showed no difference in contrast material magnitude and homogeneity between the groups. Furthermore, in the 50-mL group, the thoracic aorta was more clearly visualized because of a reduction in the opacity of the main pulmonary artery and SVC.
  
  
  CONCLUSIONS
  In our experience, administration of 50 mL of contrast medium followed by a 20-mL saline flush produces thoracoabdominal-aortoiliac MDCT angiographic examinations of effective quality in most cases.
authors.affiliation: Department of Nuclear Medicine and Diagnostic Imaging, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Shigeto
authors.initials: S
authors.lastname: Kubo
authors.forename: Eiji
authors.initials: E
authors.lastname: Tadamura
authors.forename: Masaki
authors.initials: M
authors.lastname: Yamamuro
authors.forename: Ryohei
authors.initials: R
authors.lastname: Hosokawa
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kimura
authors.forename: Toru
authors.initials: T
authors.lastname: Kita
authors.forename: Masashi
authors.initials: M
authors.lastname: Komeda
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography / Q000379:methods; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging*; D001027:Aortography / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007083:Iliac Artery / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media