Abstract:
PURPOSE:Investigation of the feasibility to perform high-resolution quantitative sodium imaging at 9.4 Tesla (T). METHODS:A proton patch antenna was combined with a sodium birdcage coil to provide a proton signal without compromising the efficiency of the X-nucleus coil. Sodium density weighted images with a nominal resolution of 1 × 1 × 5 mm(3) were acquired within 30 min with an ultrashort echo time sequence. The methods used for signal calibration as well as for B0, B1, and off-resonance correction were verified on a phantom and five healthy volunteers. RESULTS:An actual voxel volume of roughly 40 μL could be achieved at 9.4T, while maintaining an acceptable signal-to-noise ratio (8 for brain tissue and 35 for cerebrospinal fluid). The measured mean sodium concentrations for gray and white matter were 36 ± 2 and 31 ± 1 mmol/L of wet tissue, which are comparable to values previously reported in the literature. CONCLUSION:The reduction of partial volume effects is essential for accurate measurement of the sodium concentration in the human brain. Ultrahigh field imaging is a viable tool to achieve this goal due to its increased sensitivity.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Mirkes CC,Hoffmann J,Shajan G,Pohmann R,Scheffler Kdoi
10.1002/mrm.25096subject
Has Abstractpub_date
2015-01-01 00:00:00pages
342-51issue
1eissn
0740-3194issn
1522-2594journal_volume
73pub_type
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