Abstract:
:A method for quantifying the tissue sodium concentration (TSC) in the rat brain from ²³Na-MR images was developed. TSC is known to change in a variety of common human diseases and holds considerable potential to contribute to their study; however, its accurate measurement in small laboratory animals has been hindered by the extremely low signal to noise ratio (SNR) in ²³Na images. To address this, the design, construction and characterization of a double-tuned ¹H/²³Na dual resonator system for ¹H-guided quantitative ²³Na-MRI are described. This system comprises an SNR-optimized surface detector coil for ²³Na image acquisition, and a volume resonator producing a highly homogeneous B₁ field (<5% inhomogeneity) for the Na channel across the rat head. The resonators incorporated channel-independent balanced matching and tuning capabilities with active decoupling circuitry at the ²³Na resonance frequency. A quantification accuracy of TSC of <10 mM was achieved in Na-images with 1.2 µl voxel resolution acquired in 10 min. The potential of the quantification technique was demonstrated in an in vivo experiment of a rat model of cerebral stroke, where the evolution of the TSC was successfully monitored for 8 h after the stroke was induced.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Wetterling F,Tabbert M,Junge S,Gallagher L,Macrae IM,Fagan AJdoi
10.1088/0031-9155/55/24/019subject
Has Abstractpub_date
2010-12-21 00:00:00pages
7681-95issue
24eissn
0031-9155issn
1361-6560pii
S0031-9155(10)66395-6journal_volume
55pub_type
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