Gadofosveset-enhanced thoracic MR venography: a comparative study evaluating steady state imaging versus conventional first-pass time-resolved dynamic imaging

Background Dedicated blood-pool contrast agents combined with optimal angiographic protocols could improve the diagnostic accuracy of thoracic magnetic resonance angiography (MRA). $\textbf{Purpose}$ To assess the clinical utility of Gadofesveset-enhanced imaging and compare an optimized steady-state (SS) sequence against conventional first-pass dynamic multi-phase (DMP) imaging. $\textbf{Material and Methods}$ Twenty-nine patients (17 men, 12 women; mean age = 42.7, age range = 18–72 years) referred for MR thoracic venography were recruited. Imaging was performed on a 1.5T MRI system. A blood-pool contrast agent (Gadofesveset) was administered intravenously. Thirty temporal phases were acquired using DMP. This was immediately followed by a high-resolution SS sequence. Three radiologists in consensus reviewed seven thoracic vascular segments after randomizing the acquisition order. Image quality, stenoses, thromboses, and artifacts were graded using a categorical scoring system. The image quality for both approaches was compared using Wilcoxon’s signed-rank test. McNemar’s test was used to compare the proportions of stenosis grades, thrombus and artifacts. $\textbf{Results}$ SS had significantly better image quality than DMP (3.14 ± 0.73 and 2.92 ± 0.60, respectively; P 50%) than DMP; the differences in stenosis categorizations was statistically significant (P = 0.013). There was no significant difference in the proportions of vessels with thromboses (P = 0.617). DMP produced more artifacts than SS (101 versus 85); however, the difference was not statistically significant (P = 0.073). $\textbf{Conclusion}$ Gadofesveset-enhanced thoracic angiography is clinically feasible. SS imaging produces better image quality and fewer artifacts than conventional DMP imaging.The study was supported by the imaging theme of the NIHR Cambridge Biomedical Research Centre in partnership with the University of Cambridge