ADC值在腰椎间盘退行性变诊断中价值的初步研究

Assessment of Apparent Diffusion Coeficient Values in Diagnosis of Degenerated Intervertebral Lumbar Disks

目的应用能反映腰椎间盘中水分子扩散运动的平均表观扩散系数(apparent diffusion coefficent,ADC)值,探讨椎间盘髓核ADC值与椎间盘退行性变Pfirrmann分级的相关性。资料与方法对63例腰椎间盘退行性变患者进行腰椎MR常规序列和扩散加权成像(diffusion weighted imaging,DWI)扫描,并测量L1/2～L5/S1椎间盘髓核ADC值。根据Pfirrmann分级法由两名放射科医师盲法阅片将椎间盘分为Ⅰ～Ⅴ组。对比Ⅰ～Ⅴ组椎间盘髓核的平均ADC值,并对各组之间的相关关系进行分析研究。结果 63例301个腰椎间盘中,未发现符合Pfir-rmannⅠ级和Ⅱ级的椎间盘。PfirrmannⅢ～Ⅴ级椎间盘髓核平均ADC值分别为(1.59±0.23)×10-3mm2/s、(1.14±0.21)×10-3mm2/s、(0.84±0.23)×10-3mm2/s。Ⅲ～Ⅴ组椎间盘髓核的ADC值之间差异有明显的统计学意义(P<0.05)。结论腰椎间盘髓核的ADC值可以反映腰椎间盘退行性变,且随着退变程度的增加ADC值逐渐降低。

Objective To discuss the relationship between ADC values of nucleus pulposus of lumbar disks and the Pfirrmann＇s grading using the mean apparent difusion coeficient （ADC） values.Materials and Methods Conventional MRI sequence combined with diffusion weighted imaging of lumbar spine was performed in 63 patients.ADC values of each disk were measured（ L1/2-L5/S1）.Lumbar discs were graded intoⅠ-Ⅴ groups according to Pfirrmann＇s grading system by two doctors who were blind to interpret the imaging findings.The relationship among the mean ADC values of the Ⅰ-Ⅴ groups was analyzed.Results 301 discs of 63 patients were evaluated,Grade I and Grade Ⅱ discs were not observed.The mean ADC values of Grade Ⅲ-Ⅴ discs were （1.59±0.23）×10^-3 mm^2/s,（1.14±0.21）×10^-3 mm^2/s and （0.84±0.23）×10^-3 mm^2/s respectively.The mean ADC values of Ⅲ-Ⅴ groups showed significant differences （P〈0.05）.Conclusion The mean ADC values can refect degeneration of lumbar discs,furthermore,with Pfirrmann grade in lumbar intervertebral disc increase,the mean ADC values decrease.