Abstract:
:In this study, we report the use of a novel ultrashort echo time T(1)rhoT(1) sequence that combines a spin-lock preparation pulse with a two-dimensional ultrashort echo time sequence of a nominal echo time 8 microsec. The ultrashort echo time-T(1)rho sequence was employed to quantify T(1)rho in short T(2) tissues including the Achilles tendon and the meniscus. T(1)rho dispersion was investigated by varying the spin-lock field strength. Preliminary results on six cadaveric ankle specimens and five healthy volunteers show that the ultrashort echo time-T(1)rho sequence provides high signal and contrast for both the Achilles tendon and the meniscus. The mean T(1)rho of the Achilles tendon ranged from 3.06 +/- 0.51 msec for healthy volunteers to 5.22 +/- 0.58 msec for cadaveric specimens. T(1)rho increased to 8.99 +/- 0.24 msec in one specimen with tendon degeneration. A mean T(1)rho of 7.98 +/- 1.43 msec was observed in the meniscus of the healthy volunteers. There was significant T(1)rho dispersion in both the Achilles tendon and the meniscus. Mean T(1)rho increased from 2.06 +/- 0.23 to 7.85 +/- 0.74 msec in normal Achilles tendon and from 7.08 +/- 0.64 to 13.42 +/- 0.93 msec in normal meniscus when the spin-lock field was increased from 250 to 1,000 Hz.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Du J,Carl M,Diaz E,Takahashi A,Han E,Szeverenyi NM,Chung CB,Bydder GMdoi
10.1002/mrm.22474subject
Has Abstractpub_date
2010-09-01 00:00:00pages
834-42issue
3eissn
0740-3194issn
1522-2594journal_volume
64pub_type
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