- Workshop presentation
- Open Access
Repeatability and internal consistency of abdominal 2D and 4D PC MR flow measurements
© Wentland et al; licensee BioMed Central Ltd. 2012
- Published: 1 February 2012
- Renal Artery
- Flow Measurement
- Infrarenal Aorta
- Renal Vasculature
- Flow Difference
We have recently demonstrated the benefits of a radially undersampled 4D-MR flow acquisition (PC-VIPR) [1, 2] for angiographic imaging of the renal vasculature in humans  and for transstenotic pressure gradients in a swine model . Validation of velocity measurements in vivo with non-MRI methods is desirable, but not possible. The purpose of this study was to assess the repeatability of 2D and 4D-PC flow measurements in humans and to assess the internal consistency of arterial in-flow and out-flow measurements in the renal vasculature.
Total flow over the cardiac cycle was measured with in-house-developed software. To test for internal consistency, differences were computed between the suprarenal aortic flow (Qin) and the sum of flow measurements in the renal arteries and infrarenal aorta (Qout); differences were normalized by the average of Qin and Qout. 2D and 4D percent differences were compared with a Student's t-test. The repeatability of flow measurements was assessed with Pearson correlation and Bland-Altman analysis.
Flow measurements in healthy volunteers revealed that 4D measurements tended to be more internally consistent than 2D measurements, with average differences slightly greater than 10%. The repeatability of the 2D and 4D data were similar. These results are favorable compared to a previous report  comparing 2D and 4D PC flow measurements, despite the compounding error of multiple flow measurements for this check on internal consistency.
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.