Abstract:
:An eight-channel receive-only brain coil and table-top detunable volume transmit coil were developed and tested at 7 T for human imaging. Optimization of this device required attention to sources of interaction between the array elements, between the transmit and receive coils and minimization of common mode currents on the coaxial cables. Circular receive coils (85 mm dia.) were designed on a flexible former to fit tightly around the head and within a 270-mm diameter TEM transmit volume coil. In the near cortex, the array provided a fivefold increase in SNR compared to a TEM transmit-receive coil, a gain larger than that seen in comparable coils at 3 T. The higher SNR gain is likely due to strong dielectric effects, which cause the volume coil to perform poorly in the cortex compared to centrally. The sensitivity and coverage of the array is demonstrated with high-resolution images of the brain cortex.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Wiggins GC,Potthast A,Triantafyllou C,Wiggins CJ,Wald LLdoi
10.1002/mrm.20547subject
Has Abstractpub_date
2005-07-01 00:00:00pages
235-40issue
1eissn
0740-3194issn
1522-2594journal_volume
54pub_type
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