Technological advances in MRI measurement of brain perfusion.
Duyn JH, van Gelderen P, Talagala L, Koretsky A, de Zwart JA.v
Advanced MRI Laboratory, National Institutes of Health, Bethesda, Maryland 20892, USA. jhd@helix.nih.gov
Measurement of brain perfusion using arterial spin labeling (ASL) or dynamic
susceptibility contrast (DSC) based MRI has many potential important clinical
applications. However, the clinical application of perfusion MRI has been
limited by a number of factors, including a relatively poor spatial resolution,
limited volume coverage, and low signal-to-noise ratio (SNR). It is difficult to
improve any of these aspects because both ASL and DSC methods require rapid
image acquisition. In this report, recent methodological developments are
discussed that alleviate some of these limitations and make perfusion MRI
more suitable for clinical application. In particular, the availability of
high magnetic field strength systems, increased gradient performance, the use
of RF coil arrays and parallel imaging, and increasing pulse sequence
efficiency allow for increased image acquisition speed and improved SNR.
The use of parallel imaging facilitates the trade-off of SNR for increases
in spatial resolution. As a demonstration, we obtained DSC and ASL perfusion
images at 3.0 T and 7.0 T with multichannel RF coils and parallel imaging,
which allowed us to obtain high-quality images with in-plane voxel
sizes of 1.5 x 1.5 mm2).
Publication Types:
PMID: 16267852 [PubMed - indexed for MEDLINE]