The application of T1 and T2 relaxation time and magnetization transfer ratios to the early diagnosis of patellar cartilage osteoarthritis.
OBJECTIVE
We compare the T1 and T2 relaxation times and magnetization transfer ratios (MTRs) of normal subjects and patients with osteoarthritis (OA) to evaluate the ability of these techniques to aid in the early diagnosis and treatment of OA.


METHODS
The knee joints in 11 normal volunteers and 40 patients with OA were prospectively evaluated using T1 relaxation times as measured using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T2 relaxation times (multiple spin-echo sequence, T2 mapping), and MTRs. The OA patients were further categorized into mild, moderate, and severe OA.


RESULTS
The mean T1 relaxation times of the four groups (normal, mild OA, moderate OA, and severe OA) were: 487.3 +/- 27.7, 458.0 +/- 55.9, 405.9 +/- 57.3, and 357.9 +/- 36.7 respectively (p <0.001). The mean T2 relaxation times of the four groups were: 37.8 +/- 3.3, 44.0 +/- 8.5, 50.9 +/- 9.5, and 57.4 +/- 4.8 respectively (p < 0.001). T1 relaxation time decreased and T2 relaxation time increased with worsening degeneration of patellar cartilage. The result of the covariance analysis showed that the covariate age had a significant influence on T2 relaxation time (p < 0.001). No significant differences between the normal and OA groups using MTR were noted.


CONCLUSIONS
T1 and T2 relaxation times are relatively sensitive to early degenerative changes in the patellar cartilage, whereas the MTR may have some limitations with regard to early detection of OA. In addition, The T1 and T2 relaxation times negatively correlate with each other, which is a novel finding.
Yao
Weiwu
W
Department of Radiology, Shanghai No.6 People's Hospital affiliated to Shanghai Jiaotong University, Shanghai, China. yaoweiwu@yahoo.com
Qu
Nan
N
Lu
Zhihua
Z
Yang
Shixun
S
D000328:Adult; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis*; D017847:Patellar Ligament / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
Radiology. 1997 Nov;205(2):546-50
9356643
J Rheumatol. 1988 Dec;15(12):1833-40
3068365
Ann Rheum Dis. 1957 Dec;16(4):494-502
13498604
Magn Reson Imaging. 2001 Dec;19(10):1279-86
11804755
J Anat. 1994 Jun;184 ( Pt 3):477-92
7928637
J Rheumatol. 1995 Sep;22(9):1747-56
8523356
J Magn Reson Imaging. 2005 Aug;22(2):318-23
16028240
Invest Radiol. 2008 Jan;43(1):16-26
18097273
Magn Reson Med. 2001 Dec;46(6):1067-71
11746570
Radiology. 1997 Nov;205(2):551-8
9356644
Magn Reson Med. 1996 Nov;36(5):665-73
8916016
Magn Reson Med. 2001 Sep;46(3):487-93
11550240
J Magn Reson Imaging. 2003 May;17(5):603-8
12720271
Connect Tissue Res. 1989;19(2-4):149-76
2805680
Osteoarthritis Cartilage. 1998 Jan;6(1):24-32
9616436
J Orthop Res. 2006 Mar;24(3):366-74
16479569
J Magn Reson Imaging. 1999 Oct;10(4):497-502
10508315
Magn Reson Med. 1999 May;41(5):857-65
10332865
Invest Radiol. 2000 Oct;35(10):602-21
11041155
J Orthop Res. 2004 May;22(3):557-64
15099635
Radiology. 2004 Aug;232(2):592-8
15215540
Eur Radiol. 2004 Feb;14(2):184-92
14600779
Magn Reson Imaging. 2000 May;18(4):423-30
10788720
Osteoarthritis Cartilage. 2003 Oct;11(10):709-15
13129689
Clin Symp. 1995;47(2):1-32
7554763
Magn Reson Med. 2001 Jan;45(1):36-41
11146483
J Magn Reson Imaging. 2006 Apr;23(4):547-53
16523468
J Magn Reson Imaging. 2001 Jul;14(1):50-5
11436214
Magn Reson Med. 2005 Sep;54(3):507-12
16086319
Radiology. 2000 Jan;214(1):259-66
10644134
Skeletal Radiol. 2006 Dec;35(12):903-8
16738915
Osteoarthritis Cartilage. 1996 Sep;4(3):197-207
8895221