基于能谱CT动脉造影的脊髓型颈椎病脊髓前动脉血流灌注特点

Characteristics of anterior spinal artery perfusion in patients with cervical spondylotic myelopathy based on energy spectrum CT angiography

目的应用能谱CT动脉造影(CTA)研究健康人群和脊髓型颈椎病(CSM)患者颈椎脊髓前动脉(ASA)的形态和血流灌注特点。方法招募16名健康志愿者为对照组,筛选21例CSM患者为病例组,行能谱CTA检查。获取颈椎ASA重建图像,观察ASA的走行、充盈情况。以各节段ASA平均碘含量代表动脉血流灌注量,比较对照组各节段血流灌注量,计算病例组动脉受压部位的平均血流灌注减少率。结果对照组16例ASA充盈良好,其中13例在C4～6节段观察到脊髓前根动脉分支汇入ASA,自C1至C7 ASA血流灌注较均匀但呈现轻度逐渐增加的趋势。病例组21例中,9例颈椎ASA充盈良好;12例在颈髓受压节段出现ASA充盈减弱,其中4例受压节段以下的动脉充盈不良,其余8例受压节段以下动脉再次充盈,12例的受压处动脉灌注减少率为(28.64±7.73)%(16.86%～38.16%)。21例中有14例ASA在C4～6节段侧方有脊髓前根动脉分支汇入ASA。结论健康状态下颈椎ASA各节段血流灌注较均匀,部分CSM患者中可出现ASA受压,但一般不会发生完全梗阻;由于下颈椎部位脊髓前根动脉分支的汇入,部分ASA受压以下节段可重新充盈。

Objective To study the morphology and blood perfusion features of cervical anterior spinal artery（ASA） in healthy subjects and patients with cervical spondylotic myelopathy（CSM） based on energy spectrum CT angiography（CTA）. Methods Sixteen healthy volunteers were recruited in the control group,and 21 patients with CSM were included in the case group. All these subjects received energy spectrum CTA examination. After the image reconstruction of ASA,the course and the vessel filling of the ASA were observed. The average iodine content of ASA in each level was calculated to represent the blood perfusion of ASA at these levels. The blood perfusion at different levels in the control group was compared. The average decrease rate of blood perfusion at the site of compressed ASA in case group was calculated. Results The ASA of all 16 cases in the control group were well filled. It was observed that several branches of anterior radicular artery（ARA） were incorporated into ASA at C4-6 levels in 13 cases. The blood perfusion from the C1 level to C7 level was nearly equal but had the tendency of mild increase. Of 21 cases in case group,the ASA was well filled in 9 cases,and poorly filled at the same level of spinal cord compression in 12 cases. In addition,the levels of ASA below the compression were still poorly filled in 4 cases. By contrast,the filling was regained in remaining 8 cases. The decrease rate of blood perfusion at the site of compressed ASA in case group was （28.64±7.73）%（16.86%-38.16%）. ARA was incorporated into ASA at C4-6 levels in 14 cases of case group. Conclusion The blood perfusion at different levels of cervical ASA is nearly equal in healthy condition,and the perfusion of ASA at lower cervical spine will slightly increase because of the incorporation of the ARA. The ASA can be compressed on the same level of spinal cord compression in some patients with CSM. However,full obstruction of ASA would not occur. The levels of ASA below the compression can be well filled again in some patients as the incorporation of the ARA at lower cervical spine.