Yeung David K W, Wong Samuel Y S, Griffith James F, Lau Edith M C
Department of Clinical Oncology, Prince of Wales Hospital, Hong Kong, China.
J Magn Reson Imaging. 2004 Feb;19(2):222-8. doi: 10.1002/jmri.10453.
To determine the diffusion of vertebral body marrow with quantitative MR diffusion imaging and to examine whether differences exist between subjects with postmenopausal osteoporosis and premenopausal control subjects.
A total of 44 consecutive women (mean age, 70 years) with documented bone mineral density (BMD) measured by dual energy x-ray absorptiometry (T-score) and 20 normal subjects (mean age, 28 years) were examined with echo-planar diffusion imaging at 1.5 T using b values of 0, 20, 40, 60, 80, 100, 200, 300, 400, and 500 seconds/mm2. Extravascular diffusion (D) and apparent diffusion coefficient (ADC) were calculated and results from both groups compared.
Both D and ADC values tended to decrease with decreasing BMD. Mean D values were significantly lower in postmenopausal women with reduced BMD (0.42 +/- 0.12 x 10(-3) mm2/second) than normal premenopausal women (0.50 +/- 0.09 x 10(-3) mm2/second). Mean ADC values were significantly lower both in subjects with reduced BMD (0.41 +/- 0.10 x 10(-3) mm2/second) and normal BMD (0.43 +/- 0.08 x 10(-3) mm2/second) compared to normal controls (0.49 +/- 0.07 x 10(-3) mm2/second).
Accumulation of fatty bone marrow associated with osteoporosis is reflected by a decrease in D and ADC. Diffusion imaging may prove useful in the study of osteoporosis.
通过定量磁共振扩散成像确定椎体骨髓的扩散情况，并检查绝经后骨质疏松症患者与绝经前对照受试者之间是否存在差异。
共有44名连续的女性（平均年龄70岁），她们通过双能X线吸收法测量了骨矿物质密度（BMD）（T值），还有20名正常受试者（平均年龄28岁），使用1.5T的回波平面扩散成像，b值分别为0、20、40、60、80、100、200、300、400和500秒/平方毫米对其进行检查。计算血管外扩散（D）和表观扩散系数（ADC），并比较两组结果。
D值和ADC值均倾向于随BMD降低而下降。BMD降低的绝经后女性的平均D值（0.42±0.12×10⁻³平方毫米/秒）显著低于绝经前正常女性（0.50±0.09×10⁻³平方毫米/秒）。与正常对照组（0.49±0.07×10⁻³平方毫米/秒）相比，BMD降低的受试者（0.41±0.10×10⁻³平方毫米/秒）和BMD正常的受试者（0.43±0.08×10⁻³平方毫米/秒）的平均ADC值均显著降低。
骨质疏松症相关的脂肪骨髓积聚通过D值和ADC值的降低得以体现。扩散成像可能在骨质疏松症研究中证明有用。
