椎间盘退变Pfirrmann分级的髓核磁共振扩散张量成像参数值研究

Study on the magnetic resonance diffusion tensor imaging parameters of the nucleus pulposus of degenerated intervertebral disks according to Pfirrmann grading

目的：探讨依据Pfirrmann分级的椎间盘髓核磁共振扩散张量成像相对T2值、ADC值、FA值的改变。方法对72例患者和30名健康志愿者均行腰椎常规MRI和轴位DTI序列检查。将正常与退变椎间盘分为1～5级，统计分析椎间盘髓核的相对T2值、ADC值和FA值关系。结果1、4、5级椎间盘相对T2值与ADC值呈正相关（ r值分别为0{．4563、0．6024和0．8601， P ＜0．05），与FA值呈负相关（ r值分别为-0．3851、-0．5356和-0．8287， P ＜0．05）。2级椎间盘，相对 T2值与 ADC 值正相关（ r ＝0．4941， P ＜0．01），相对T2值与FA值无相关性（ r ＝-0．2998， P ＞0．05）。3级椎间盘相对T2值与ADC值、相对T2值与FA值无相关性（ r值分别为0．2945、-0．0954， P ＞0．05）。 Pfirrmann分级分别与相对T2值、FA值、ADC值有相关性（ P ＜0．01）。1级椎间盘与其余各级椎间盘的相对T2值、FA值、ADC值差异均有统计学意义（ P ＜0．05）。结论 DTI可以作为判断椎间盘功能状况的有用指标。退变程度轻-中度的椎间盘可能经过治疗逆转退变过程。

Objective To quantitatively analyze the changes of magnetic resonance diffusion tensor imaging parameters of degenerated intervertebral disks according to Pfirrmann grading .Methods 72 patients and 30 healthy volunteers were examined by 3.0T MRI for T1,T2 and DTI scan.According to T2WI of disks,the normal and degenerated intervertebral disks were divided into five groups ,and the correlation among relative T2 values,ADC values and FA values in the five groups was analyzed .Results The relative T2 values in 1,4 and 5 grade intervertebral disk were positively correlated with those of ADC （ P 〈0.05）,however,which were negatively related to those of FA （P 〈0.05）.The relative T2 values in grade 2 intervertebral disk were positively correlated to those of ADC （ r =0.4941, P 〈0.01）,however,which were not related with those of FA （ r =-0.2998, P〉0.05）.The relative T2 values in grade 3 intervertebral disk were not correlated with those of ADC ,FA （ P 〉0.05）.However the parameters value according to Pfirrmann grading was related to that of relative T 2,FA,ADC （P 〈0.01）.There were significant differences in relative T 2 values,FA,ADC between grade 1 intervertebral disk and the other grade intervertebral disks （ P 〈0 .05 ） .Conclusion DTI can be regarded as a useful indicator to evaluate intervertebral disk function .The degeneration process of slight and moderate degree degenerated disks may be reversed through treatment .