title: Non-contrast-enhanced MR angiography for selective visualization of the hepatic vein and inferior vena cava with true steady-state free-precession sequence and time-spatial labeling inversion pulses: preliminary results.
abstract: OBJECTIVE
  To selectively visualize the hepatic vein and inferior vena cava (IVC) using three-dimensional (3D) true steady-state free-precession (SSFP) MR angiography with time-spatial labeling inversion pulse (T-SLIP), and to optimize the acquisition protocol.
  
  
  METHODS
  Respiratory-gated 3D true SSFP scans were conducted in 23 subjects in combination with two different T-SLIPs (one placed in the thorax to suppress the arterial signal and the other in the abdomen to suppress the portal venous signal). One of the most important factors was the inversion time (TI) of abdominal T-SLIP, and the image quality was evaluated at four different TIs of 800, 1200, 1600, and 2000 msec in terms of relative signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and mean visualization scores.
  
  
  RESULTS
  No significant difference was observed in SNR and CNR between each TI. However, IVC visualization scores were better at TIs of 1600 and 2000 msec, and overall image quality was better at TIs of 1200 and 1600 msec. Therefore, the TI of 1600 msec was considered to provide the optimal balance between IVC visualization and signal suppression of the portal vein in our protocol.
  
  
  CONCLUSIONS
  True SSFP scan with T-SLIPs enabled selective visualization of the hepatic vein and IVC without an exogenous contrast agent.
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan. kotaro@kuhp.kyoto-u.ac.jp
authors.forename: Kotaro
authors.initials: K
authors.lastname: Shimada
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Isoda
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Okada
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Kamae
authors.forename: Yoji
authors.initials: Y
authors.lastname: Maetani
authors.forename: Shigeki
authors.initials: S
authors.lastname: Arizono
authors.forename: Yuusuke
authors.initials: Y
authors.lastname: Hirokawa
authors.forename: Toshiya
authors.initials: T
authors.lastname: Shibata
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016477:Artifacts; D005260:Female; D006503:Hepatic Veins; D006801:Humans; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D014682:Vena Cava, Inferior