磁共振常规图像诊断腰椎间盘突出的不足:与手术结果对比研究

目的通过与手术结果比较,找出目前腰椎MR横轴位及矢状位图像诊断腰椎间盘突出的缺陷与不足,并提出解决方法。材料与方法回顾100例经手术证实存在腰椎间盘突出并术前有MR平扫资料的病例,观察MR常规序列(包括矢状位T1WI、T2WI及压脂序列,横轴位T2WI),分别以手术结果为标准,计算矢状位与横轴位图像诊断腰椎间盘突出的准确率及对腰椎间盘突出特殊征象的检出率,并分析横轴位及矢状位图像的漏诊原因。结果 MR横轴位图像对腰椎间盘突出总体诊断准确率为93.6%,矢状位为84.8%,前者高于后者(χ~2=5.02,P0.05);横轴位图像对腰椎间盘向上下方突出或脱出和髓核游离的检出率低(36.00%、45.45%),矢状位检出率高(96.00%、100.00%),前者检出率明显低于后者(χ~2=20.05、8.25,P0.05)。横轴位对椎间孔型及椎间孔外侧型椎间盘突出的检出率高(96.30%、88.89%),矢状位上分别为74.07%、38.89%,前者检出率明显高于后者(χ~2=5.28、9.75,P0.05)。横轴位局限于椎间隙层面的扫描范围和矢状位缺乏参照是MR常规图像漏诊椎间盘突出的主要原因。结论 MR常规图像对特殊类型椎间盘突出的漏诊,可以通过密切结合MR矢状位图像,根据需要局部增加横轴位扫描层面或结合三维电子计算机断层扫描(computed tomography,CT)检查来解决。

The shortcomings of conventional MR images in the diagnosis of lumbar disc herniation: comparative study with the results of surgical operation

Objective: To find out the shortcomings of the MR axial and sagittal images in the diagnosis of lumbar disc herniation by comparing with results of surgical operation and MR sagittal image and find out solutions. Materials and Methods: The MR images of 100 cases with lumbar disc herniation confirmed by surgical operation were retrospectively analyzed. MR conventional sequences (sagittal T1WI, T2WI and fat-suppressing sequences, axial T2WI) were observed. Using the surgical results as the standard, the diagnostic accuracy of disc herniation and the detection rate of the special signs of the disease were calculated and compared on sagittal and axial images, and the causes of misdiagnosis on axial and sagittal images were analyzed. Results:The accuracy of the diagnosis of the lumbar disc herniation using MR sagittal, axial images was 84.8%, 93.6%, respectively. Between axial and sagittal images there were significant differences (χ2=5.02, P<0.05); The detection rates of the lumbar disc herniation or prolapse shifting upward or downward and dissociate nucleus on axial MR images were 36.00% and 45.45%, respectively, which were significantly lower than that on the sagittal images of 96.00% and 100.00% (χ2=20.05, 8.25, P<0.05).The detection rate of lumbar disc herniation of foraminal and intervertebral foramen lateral type on axial images were 96.30% and 88.89%, respectively, which is significantly higher than that on the sagittal images of 74.07% and 38.89% (χ2=5.28, 9.75, P<0.05). The main reasons of transverse axial image misdiagnosis of the herniated disk were the scanning range limited to the intervertebral space. Conclusions: MR axial and sagittal images have their own advantages in the diagnosis of the lumbar disc herniation. To pay more attention to MR sagittal images, to increase the range of axial scanning when necessary, to perform 3D CT can avoid the misdiagnosis of the special intervertebral disc protrusion on the MR images.