title: Non-contrast-enhanced MR hepatic arteriography with time-spatial labeling inversion pulses: comparison of imaging with flow-in and modified flow-out methods.
abstract: Background In non-contrast-enhanced magnetic resonance (MR) arteriography, the flow-out method using a selective tagging pulse with a long inversion time (TI) and a non-selective inversion recovery pulse with a short TI (the modified flow-out method) might further contribute to the suppression of background signal and facilitate improved visualization of the hepatic artery. However, no report has focused on the image quality of non-contrast-enhanced MR arteriography using the modified flow-out method. Purpose To compare the flow-in method with the modified flow-out method and to determine which method better visualizes the hepatic artery. Material and Methods Twenty-seven healthy volunteers were examined using respiratory-triggered three-dimensional true steady-state free-precession MR with two selective inversion recovery pulses (the flow-in method) or with one tagging pulse and one non-selective inversion recovery pulse (the modified flow-out method). Results Artery-to-liver contrast was signiﬁcantly increased in the modified flow-out method relative to the flow-in method ( P < 0.05). In all analyses of vessel visibility, non-contrast-enhanced MR arteriography using the modified flow-out method exhibited higher scores than with the flow-in method. With respect to overall image quality, the modified flow-out method was signiﬁcantly better than the flow-in method ( P < 0.01). Conclusion The modified flow-out method for non-contrast-enhanced MR angiography is a promising technique for visualizing the hepatic artery.
authors: Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors: Hiroyoshi
authors: H
authors: Isoda
authors: Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors: Akihiro
authors: A
authors: Furuta
authors: Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors: Tsuyoshi
authors: T
authors: Ohno
authors: Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors: Kaori
authors: K
authors: Togashi
mesh_terms: D000328:Adult; D005260:Female; D006499:Hepatic Artery / Q000000981:diagnostic imaging* / Q000502:physiology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors
keywords: Non-contrast-enhanced hepatic magnetic resonance (MR) arteriography; balanced steady-state free-precession; flow-in method; modified flow-out method; time spatial labeling inversion pulse