能谱CT预测腰椎间盘Pfirrmann分级的初步研究

A Preliminary Study of Spectral CT in Predicting Pfirrmann Grading of Lumbar Intervertebral Disc

目的:探讨能谱CT物质分离技术对腰椎间盘退行性病变Pfirrmann分级的预测价值。方法:回顾性分析2020年10月至2021年2月我院腰椎间盘突出患者30例,分别行能谱CT扫描及MRI扫描,将Pfirrmann分级中1~3级归入低级别组,4~5级归入高级别组。利用能谱后处理分析软件在相同ROI下分别测得椎间盘的水(钙)浓度、水(HAP)浓度、钙(水)浓度、HAP(水)浓度及Eff-Z。采用独立样本t检验比较各参数之间有无差异,并进一步绘制ROC曲线,利用曲线下面积衡量诊断效能并选择最佳诊断阈值。结果:低级别椎间盘的水(钙)浓度、水(HAP)浓度高于高级别椎间盘水(钙)浓度、水(HAP)浓度,低级别钙浓度、HAP浓度及Eff-Z低于高级别椎间盘钙浓度、HAP浓度及Eff-Z,差异具有统计学意义。ROC曲线显示水(钙)浓度、水(HAP)浓度对区分低级别与高级别椎间盘的诊断效能较低;钙浓度具有一定的诊断效能;HAP及Eff-Z具有较高的诊断效能,尤其以Eff-Z为著,AUC为0.97,以7.69为标准区分低级别与高级别椎间盘的敏感性及特异性分别为96.20%和94.12%。结论:能谱CT多参数定量分析对区分低级别与高级别椎间盘具有一定价值。

Objective:To investigate the predictive value of material separation technology of spectral CT in Pfirrmann grading of lumbar intervertebral disc degeneration.Methods:Retrospective analysis was performed on 30 patients with lumbar disc herniation in our hospital from October 2020 to February 2021.Spectral CT scan and MRI scan were performed respectively.Grade 1-3 of Pfirrmann grading was classified into low grade group,while grade 4-5 was classified into high grade group.Water(calcium)concentration,water(HAP)concentration,calcium(water)concentration,HAP(water)concentration and Eff-Z of intervertebral disc were measured by spectral postprocessing analysis software in the same ROI.Independent sample t est was used to compare the differences among parameters,furthermore,the ROC curve was drawn.The area under the curve was used to evaluate the diagnostic efficiency and select the optimal diagnostic threshold.Results:The concentrations of water(calcium)and water(HAP)in low-grade intervertebral discs were higher than those in high-grade intervertebral discs,while the concentrations of water(calcium),water(HAP)and Eff-Z in low-grade intervertebral discs,were lower than those in high-grade intervertebral discs,which held statistical significance.The ROC curve showed that water(calcium)concentration and water(HAP)concentration were less effective in diagnosing the difference between low-grade and high-grade discs.Calcium concentration holds certain diagnostic efficacy.HAP and Eff-Z hold high diagnostic efficacy.while Eff-Z shows better diagnostic efficacy with AUC of 0.97.Taking 7.69 as the standard,the sensitivity and specificity of differentiating low-grade and high-grade intervertebral discs are respectively 96.25%and 96.00%.Conclusion:Spectral CT with multi-parameters quantitative analysis holds certain value in distinguishing low grade and high grade intervertebral discs.