Abstract:
:The incorporation of RF coils into the tips of intravascular devices has been shown to enable the localization of catheters and guidewires under MR guidance. Furthermore, such coils can be used for endoluminal imaging. The long cable required to connect the coil with the scanner input inadvertently acts as a dipole antenna which picks up RF energy from the body coil during transmit. Currents are induced on the cable which can lead to localized heating of surrounding tissue. Cables of various lengths were measured to determine if a resonance in the heating as a function of cable length could be found. Coaxial chokes with a length of lambda/4 were added to coaxial cables to reduce the amplitude of the currents induced on the cable shield. A 0.7-mm diameter triaxial cable, small enough to fit into a standard intravascular device, was developed and measured both with and without a coaxial choke. It is demonstrated that resonant heating does occur and that it can be significantly reduced by avoiding a resonant length of cable and by including coaxial chokes on the cable.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Ladd ME,Quick HHdoi
10.1002/(sici)1522-2594(200004)43:4<615::aid-mrm19subject
Has Abstractpub_date
2000-04-01 00:00:00pages
615-9issue
4eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(200004)43:4<615::AID-MRM19journal_volume
43pub_type
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更新日期:2011-12-01 00:00:00
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更新日期:2012-02-01 00:00:00
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更新日期:2017-01-01 00:00:00
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更新日期:2020-07-01 00:00:00
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