Abstract:
PURPOSE:To improve the imaging quality of vessel walls with an endoesophageal Wireless Amplified NMR Detector (WAND). METHODS:A cylindrically shaped double-frequency resonator has been constructed with a single metal wire that is self-connected by a pair of nonlinear capacitors. The double-frequency resonator can convert wirelessly provided pumping power into amplified MR signals. This compact design makes the detector easily insertable into a rodent esophagus. RESULTS:The detector has good longitudinal and axial symmetry. Compared to an external surface coil, the WAND can enhance detection sensitivity by at least 5 times, even when the distance separation between the region of interest and the detector's cylindrical surface is twice the detector's own radius. Such detection capability enables us to observe vessel walls near the aortic arch and carotid bifurcation with elevated sensitivity. CONCLUSION:A cylindrical MRI detector integrated with a wireless-powered amplifier has been developed as an endoesophageal detector to enhance detection sensitivity of vessel walls. This detector can greatly improve the imaging quality for vessel regions that are susceptible to atherosclerotic lesions. Magn Reson Med 78:2048-2054, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Zeng X,Barbic M,Chen L,Qian Cdoi
10.1002/mrm.26562subject
Has Abstractpub_date
2017-11-01 00:00:00pages
2048-2054issue
5eissn
0740-3194issn
1522-2594journal_volume
78pub_type
杂志文章abstract:PURPOSE:A ghost correction strategy for Simultaneous Multi-Slice (SMS) EPI methods that provides improved ghosting artifact reduction compared to conventional methods is presented. Conventional Nyquist ghost correction methods for SMS-EPI rely on navigator data that contain phase errors from all slices in the simultane...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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pub_type: 临床试验,杂志文章
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journal_title:Magnetic resonance in medicine
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pub_type: 临床试验,杂志文章
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更新日期:2002-12-01 00:00:00
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更新日期:2010-03-01 00:00:00
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doi:10.1002/mrm.1910390516
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更新日期:2018-03-01 00:00:00
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