Flow-independent T(2)-prepared inversion recovery black-blood MR imaging.
OBJECTIVE
To develop a magnetization preparation method to achieve robust, flow-independent blood suppression for cardiac and vascular magnetic resonance imaging (MRI).


METHODS
T(2)Prep-IR sequence consists of a T(2) preparation followed by a nonselective adiabatic inversion pulse. T(2)Prep separates the initial longitudinal magnetization of arterial wall from lumen blood. After the inversion recovery pulse the imaging acquisition is then delayed for a period that allows the blood signal to approach the zero-crossing point. Compared to the conventional double inversion recovery (DIR) preparation, T(2)Prep-IR prepares all the spins regardless of their velocity and direction. T(2)Prep-IR was incorporated into the fast spin echo and fast gradient echo acquisition sequences and images in various planes were acquired in the carotid arteries, thoracic aorta, and heart of normal volunteers. Blood suppression and image quality were compared qualitatively between two different preparations.


RESULTS
For in-plane flow carotid images, persistent flow-related artifacts on the DIR images were removed with T(2)Prep-IR. For cardiac applications, T(2)Prep-IR provided robust blood suppression regardless of the flow direction and velocity, including the cardiac long-axis views and the aorta that are often problematic with DIR.


CONCLUSIONS
T(2)Prep-IR may overcome the flow dependence of DIR by providing robust flow-independent black-blood images.
Liu
Chia-Ying
CY
Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA. Cliu51@jhmi.edu
Bley
Thorsten A
TA
Wieben
Oliver
O
Brittain
Jean H
JH
Reeder
Scott B
SB
D000328:Adult; D000465:Algorithms; D001783:Blood Flow Velocity; D002339:Carotid Arteries / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity