Abstract
Purpose
To prospectively evaluate the technical feasibility of a highly accelerated pulmonary MR perfusion protocol at 3.0T using a blood pool contrast agent in a swine model.
Materials and Methods
Twelve pigs underwent time‐resolved pulmonary MR angiography (MRA) on a 3.0T MR system under anesthesia and controlled mechanical ventilation. After intravenous injection of 0.05 mmol/kg of Gadomer‐17 at 4 mL/second, a fast time‐resolved MRA sequence with temporal echo‐sharing (three segmented k‐space) and highly accelerated parallel acquisition was used to acquire 3D data sets with an in‐plane resolution of 1 × 1 mm^2^ (slice thickness = 6 mm) and temporal resolution of one second. Image quality was evaluated independently by two radiologists, and quantitative analysis of perfusion parameters was performed using pre‐released perfusion software.
Results
All studies were identified by both readers as having diagnostic image quality (range = 2–3, median = 3) and there was excellent interobserver agreement (κ = 0.89; 95% CI = 0.83, 0.95). A quantitative analysis of perfusion indices was performed, with excellent overall goodness‐of‐fit (χ^2^ value = 1.4, degree of freedom (DF) = 1). Successfully derived perfusion parameters included the time to peak (TTP, 5.1 ± 0.7 second), mean transit time (MTT, 6.6 ± 0.9 second), maximal signal intensity (MSI, 1051.2 ± 718.9 arbitrary units [A.U.]), and maximal upslope of the curve (MUS, 375.9 ± 263.4 A.U./second).
Conclusion
3.0T pulmonary MR perfusion using a blood pool contrast agent in a swine model is feasible. The higher available signal‐to‐noise ratio (SNR) at 3.0T and the high T1 relaxivity of Gadomer‐17 effectively support highly accelerated parallel acquisition, and improve the performance of time‐resolved pulmonary MRA. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.