Ultrafast CEST imaging

Jörg Döpfert; Moritz Zaiss; Christopher Witte; Leif Schröder

doi:10.1016/j.jmr.2014.03.008

Ultrafast CEST imaging

J Magn Reson. 2014 Jun:243:47-53. doi: 10.1016/j.jmr.2014.03.008. Epub 2014 Mar 20.

Authors

Jörg Döpfert¹, Moritz Zaiss², Christopher Witte³, Leif Schröder⁴

Affiliations

¹ Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125 Berlin, Germany. Electronic address: doepfert@fmp-berlin.de.
² German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
³ Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125 Berlin, Germany.
⁴ Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125 Berlin, Germany. Electronic address: lschroeder@fmp-berlin.de.

PMID: 24721681
DOI: 10.1016/j.jmr.2014.03.008

Abstract

We describe a new MR imaging method for the rapid characterization or screening of chemical exchange saturation transfer (CEST) contrast agents. It is based on encoding the chemical shift dimension with an additional gradient as proposed in previous ultrafast CEST spectroscopy approaches, but extends these with imaging capabilities. This allows us to investigate multiple compounds simultaneously with an arbitrary sample tube arrangement. The technique requires a fast multislice readout to ensure the saturation is not lost during data acquisition due to T1 relaxation. We therefore employ radial subsampling, acquiring only 10 projections per CEST image with a 128×128 matrix. To recover the images, we use a heuristic reconstruction algorithm that incorporates low rank and limited object support as prior knowledge. This way, we are able to acquire a spectral CEST data set consisting of 15 saturation offsets more than 16 times faster than compared with conventional CEST imaging.

Keywords: Chemical exchange; High-throughput screening; PARACEST agents; Ultrafast CEST imaging.

Publication types

Research Support, Non-U.S. Gov't