Measurement of R1 dynamics using sliding window-DESPOT.

Medical Physics in Radiology, German Cancer Research Center, Heidelberg, Germany.
Journal of Magnetic Resonance Imaging (Impact Factor: 2.79). 11/2009; 30(5):1163-70. DOI: 10.1002/jmri.21946
Source: PubMed

ABSTRACT To measure longitudinal relaxation rate (R1) changes during contrast agent studies using a driven equilibrium single pulse observation of T1 (DESPOT) method with a sliding window (sw) acquisition.
A sw-DESPOT technique was implemented that uses several three-dimensional (3D) image data sets to calculate R1 with a temporal resolution of only a single data set. Different sources of systematic errors were studied in simulations, and the technique was tested in a tumor-bearing mouse using an intravascular contrast agent.
Consistent concentration distributions of the CA were calculated with a temporal resolution of 10 s.
Sw-DESPOT offers a precise and fast method to monitor the CA dynamics in 3D volumes.

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