Abdominal aorta: evaluation with dual-source dual-energy multidetector CT after endovascular repair of aneurysms--initial observations

Radiology. 2008 Nov;249(2):692-700. doi: 10.1148/radiol.2492080359. Epub 2008 Sep 23.


Purpose: To evaluate the possible radiation dose reduction facilitated by using dual-energy (DE) multidetector computed tomography (CT) after endovascular repair of abdominal aortic aneurysms (AAAs).

Materials and methods: This prospective study was HIPAA compliant and institutional review board approved. Twenty-two patients who previously had undergone endovascular repair of AAAs underwent 24 DE multidetector CT examinations, which were performed with a 64-detector scanner. Initial nonenhanced CT was followed by arterial phase and venous phase acquisitions. Virtual nonenhanced, pure 80-kVp, and weighted-average peak voltage CT data sets were generated from the venous acquisition. Two independent readers interpreted the virtual nonenhanced and DE weighted-average CT data for the presence or absence of endoleaks. These interpretations were compared with the clinical interpretations of the data performed by a different radiologist by using true nonenhanced, arterial phase, and venous phase data. Region-of-interest measurements of the abdominal aorta and of the region of the endoleaks were obtained. Effective radiation dose was calculated.

Results: Both independent readers' interpretations of the virtual nonenhanced and weighted-average venous CT data revealed six type II endoleaks. There were no false-positive or false-negative findings. Aortic attenuation during the arterial, 80-kVp venous, and weighted-average data acquisitions were 288, 213, and 150 HU, respectively. The attenuation of the endoleaks was higher during the 80-kVp acquisition (P < .03) than during the arterial phase and weighted-average venous phase acquisitions. The mean effective dose for DE venous phase CT was 11.1 mSv compared with 27.8 mSv for standard triple-phase CT with a single-source configuration.

Conclusion: Preliminary observations suggest that obtaining DE multidetector CT data by using a single 60-second contrast material-enhanced acquisition may be all that is required for surveillance after endovascular repair of AAA.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aorta, Abdominal / diagnostic imaging*
  • Aorta, Abdominal / surgery
  • Aortic Aneurysm, Abdominal / diagnostic imaging
  • Aortic Aneurysm, Abdominal / surgery*
  • Contrast Media
  • Female
  • Humans
  • Iohexol / analogs & derivatives
  • Male
  • Middle Aged
  • Postoperative Complications / diagnostic imaging*
  • Prospective Studies
  • Radiation Dosage
  • Radiographic Image Interpretation, Computer-Assisted
  • Sensitivity and Specificity
  • Tomography, X-Ray Computed / methods*


  • Contrast Media
  • Iohexol
  • iopromide