肥胖与正常体重青年人腰椎间盘磁共振T_2-mapping对照研究

Control study on young people with obesity and normal body weight by lumbar magnetic resonance T_2-mapping

目的利用磁共振T2-mapping探讨肥胖对腰椎间盘退变的影响。方法 30例单纯性肥胖和30例正常体重健康志愿者均行腰椎常规MRI序列矢状位及T2-mapping扫描,得到T2-mapping原始图及伪彩图,并测量两组L1~S1椎间盘髓核的T2值;组内不同节段髓核T2值比较用ANOVA分析,两两比较用LSD检验;两组间对应节段髓核T2值用两样本独立t检验。结果肥胖组:髓核T2值范围79.50~123.50ms;30例L1~S1各节段髓核T2值均数范围(89.82±6.34)ms^(112.65±5.75)ms。对照组:髓核T2值范围91.70~145.40ms;30例L1~S1各节段髓核T2值均数范围(108.17±1 0.37)ms^(126.65±10.22)ms。统计检验结果:肥胖组组内仅L2~3与L4~5之间差别无统计学意义(P=0.096),其余两两间差别均有统计学意义(P<0.05);对照组组内L1~2与L5~S1、L2~3与L4~5、L2~3与L5~S1之间差别无统计学意义(P>0.05),其余两两间差别均有统计学意义(P<0.05);两组间除L1~2椎间盘之间差别无统计学意义之外(P>0.05),其余节段T2值差别均有统计学意义(P<0.05)。结论磁共振T2-mapping能发现腰椎髓核退变早期的生化成份的变化;肥胖可能促使或加速腰椎髓核退变。

Objective To explore the impact of obesity on lumbar disc degeneration using magnetic resonance T2-mapping.Methods Thirty volunteers with simple obese and 30 healthy volunteers with normal body weight undwewent sagittal lumbar conventional sequence MRI scan and magnetic resonance T2-mapping scan,and then obtained original map and pseudo-color map of T2-mapping.T2 values of L1～S1intervertebral disc nucleus pulposus of the two groups were measured respectively.ANOVA was used for hypothesis test on T2 values of nucleus pulposus from different levels within group,LSD test was used for paired comparison.For T2 values of nucleus pulposus from corresponding levels between the two groups,t test of two independent samples was used.Results Obesity group：T2 values of nucleus pulposus were from 79.50 ms to 123.50ms;Mean T2 values of nucleus pulposus in each level of L1～S1 were from（89.82±6.34）ms to（112.65±5.75）ms.T2 values of nucleus pulposus were from 91.70 ms to 145.40 ms in normal group;Mean T2 values of nucleus pulposus in each levels of L1～S1 were from（108.17±10.37）ms to（126.65±10.22）ms.Significant differences were found in the paired comparisons of L1～S1（P〈0.05）in obesity group except the difference between L2～3and L4～5（P〉0.05）;No significant differences were found between L1～2and L5～S1,between L2～3and L4～5,and between L2～3and L5～S1in normal group（P〉0.05）,while other paired comparisons all showed statistically significant differences（P〈0.05）.Significant differences of T2 values were found in the corresponding level（P〈0.05）between obesity group and normal group except L1～2（P〉0.05）.Conclusion Magnetic resonance T2-mapping can early detect changes of biochemical ingredients in early lumbar nucleus pulposus degeneration.Obesity may be one of the reasons for promotion or acceleration of lumbar nucleus pulposus degeneration.