Abstract:
:Proteoglycan (PG) depletion-induced changes in T1rho (spin-lattice relaxation in rotating frame) relaxation and dispersion in articular cartilage were studied at 4T. Using a spin-lock cluster pre-encoded fast spin echo sequence, T1rho maps of healthy bovine specimens and specimens that were subjected to PG depletion were computed at varying spin-lock frequencies. Sequential PG depletion was induced by trypsinization of cartilage for varying amounts of time. Results demonstrated that over 50% depletion of PG from bovine articular cartilage resulted in average T1rho increases from 110-170 ms. Regression analysis of the data showed a strong correlation (R2 = 0.987) between changes in PG and T1rho. T1rho values were highest at the superficial zone and decreased gradually in the middle zone and again showed an increasing trend in the region near the subchondral bone. The potentials of this method in detecting early degenerative changes of cartilage are discussed. Also, T(1rho)-dispersion changes as a function of PG depletion are described.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Akella SV,Regatte RR,Gougoutas AJ,Borthakur A,Shapiro EM,Kneeland JB,Leigh JS,Reddy Rdoi
10.1002/mrm.1208subject
Has Abstractpub_date
2001-09-01 00:00:00pages
419-23issue
3eissn
0740-3194issn
1522-2594pii
10.1002/mrm.1208journal_volume
46pub_type
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