Comparison of apparent diffusion coefficient and T2 relaxation time variation patterns in assessment of age and disc level related intervertebral disc changes.
OBJECTIVE
To compare the variation patterns of ADC and T2 values in different age and intervertebral disc (IVD) levels, thus to identify their sensitivities in assessing age and disc level related IVDs changes.


METHODS
The T2 and ADC values were recorded from 345 IVDs of 69 volunteers. Kendall's correlation analysis was used to identify the relationship between age and T2/ADC mean values respectively. The one-way analysis of variance (ANOVA) with post hoc analysis was then applied to test the differences of T2 and ADC values among different IVD levels and age groups, followed by linear regression analysis between age (<45 and >45 years) and T2/ADC mean values. This study was approved by the Ethics Committee of the Chinese Academy of Medical Sciences and the Peking Union Medical College Hospital.


RESULTS
Significant negative correlation was observed between age and T2/ADC mean values. The T2 and ADC values showed significant differences among IVD levels and among age groups except for T2 values in age group 1 (25-34 years) and group 2 (35-44 years), and for ADC values at L1-2 level. Both T2 and ADC values showed significant differences between young (age<45 years) and elderly group (age>45 years) at each IVD level. A linear relationship was observed between age and T2/ADC mean values in the elderly group as well as in the young group for the ADC mean values, while no such tendency was identified in the young group for the T2 mean values.


CONCLUSIONS
ADC values may be a more sensitive parameter than T2 in assessing age and disc level related intervertebral disc changes.
Department of Orthopedics, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, PR China.
Nan
N
Wu
Hao
H
Liu
Jun
J
Chen
Luo
L
Zhao
Wei
W
Zuo
Yue
Y
Ming
Sen
S
Liu
Jiaqi
J
Liu
Xinlin
X
Su
Baoxiang
B
Gao
Zhiquan
Z
Tang
Guixing
G
Qiu
Guolin
G
Ma
Zhihong
Z
Wu
D000328:Adult; D017677:Age Distribution; D000375:Aging; D000704:Analysis of Variance; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000033:anatomy & histology*; D016014:Linear Models; D008159:Lumbar Vertebrae / Q000033:anatomy & histology; D008297:Male; D008875:Middle Aged; D013997:Time Factors