旋转手法对不稳定型脑动脉粥样斑块及脑血流动力学的影响

Since Cervical rotatory manipulation has been widely used in patient care, it is generating a lot of attention and interest in its safety and rational application. Of particular focus is the influence of this technique on atheroslcerotic plaque stability. The purpose of this study was to investigate the effect of cervical rotatory manipulation on stability of atherosclerotic plaque and the tissue structures of arterial wall using methods of pathology and scanning electron microscopy in animal models. A human-computer interaction, realistic three-dimensional environment of circle of Willis will was constructed by VR technology, that integrates a variety of image data. Also, the hemodynamic model of circle of Willis was built with 3D-CTA reconstruction techniques. Blood flow dynamics in several common clinical conditions, such as stenosis or occlusion of anterior or posterior communicating artery were studied during cervical rotary manipulation in the hemodynamic model, and the verification by TCD in the patients with cerebral atherosclerosis and variations. The three-dimensional carotid artery and vertebral artery with cerebral atherosclerosis and normal in segment from occipital to cervical spine was reconstructed by MRA, changes of length and diameter of the arteries will be three-dimensional displayed and measured during the manipulation. The effect of the manipulation on cerebral blood flow, size and position of atherosclerotic plaque was detected by TCD and color Doppler techniques on the patients. This will allow us to better understand the effect of cervical rotatory manipulation on hemodynamics and atherosclerotic plaque stability in patients with cerebral arteriosclerosis and circle of Willis variations. Consequently, this research will provide imaging driven evidence for the safety of cervical rotary manipulation.

颈椎旋转手法临床应用广泛，其安全性及合理应用日益受到重视。本课题拟采用病理及扫描电镜等方法研究颈椎旋转手法对动脉粥样硬化动物模型的斑块稳定性及动脉壁组织结构的影响。应用融合多种影像资料于一体的VR技术，构建人机互动立体、逼真的Willis环三维环境，结合3D-CTA重建技术建立其血流动力学模型。模拟旋转手法时几种常见变异，如前或后交通动脉狭窄或闭塞时的血流动力学变化，并选用有相应变异及脑动脉粥样硬化患者，应用TCD检测验证。利用MRA三维重建颈枕段正常和脑动脉粥样硬化者的椎动脉及颈内动脉，三维显示及测量旋转手法作用时其长度和管腔的变化；并以TCD和彩色多普勒检测旋转手法时脑血流变化及对动脉粥样硬化斑块大小和位置的影响。通过研究，明确颈椎旋转手法对存在Willis环变异时脑动脉硬化患者的血流动力学及动脉粥样硬化斑块稳定性的影响，以期为临床安全合理地使用旋转手法提供实验基础和科学依据。

背景：上世纪三十年代，临床上开始出现有关颈部推拿后患者出现诸如眩晕、脑卒中甚至死亡等严重并发症的报道。关于颈部推拿手法的安全性问题已成为推拿学科界的争议焦点。 .目的：探索颈部推拿手法是否可伤及已发生动脉硬化的动脉组织结构，是否可促进硬化斑块的发展或促使其脱落。明确willis环存在变异时，颈椎旋转手法对其血流动力学的影响，以提高颈部推拿手法的安全性，减少推拿所致脑血管损伤。 方法：本研究分为动物实验、在体研究和构建模型等三方面的研究。（1）动物实验研究主要包括：①颈椎旋转手法/推桥弓手法对兔子粥样斑块期颈动脉拉伸力学性能的影响；②颈椎旋转手法/推桥弓手法对粥样硬化性颈动脉血流动力学的影响； ③颈椎旋转手法/推桥弓手法对兔颈动脉粥样硬化血管内膜超微结构的影响。（2）在体研究是对因颈椎病正在进行颈椎旋转手法和因高血压病进行推桥弓治疗的患者，于治疗前、治疗半月后、治疗后半年分别进行检测斑块的变化情况。并利用MRA三维重建图像，研究颈椎旋转手法对颈动脉及椎动脉的牵拉作用。（3）构建Willis环是以VR技术和几何模型进行建模及分析。几何模型是先确定Willis环模型各构成部分的几何参数、计算模型边界条件和血液参数设置。而后进行网格划分和非结构化网格。最后进行模拟旋转手法时Willis环瞬态血液动力学计算。结果：（1）相对正常颈动脉而言，颈动脉粥样硬化斑块的存在会降低颈动脉的拉伸力学性能，而对存在颈动脉粥样硬化的兔子进行颈部推拿，会进一步降低颈动脉的拉伸力学性能；（2）颈部推拿会影响颈动脉粥样硬化兔子的颈动脉血流变化，但对正常兔子无明显影响；(3) 颈部推拿会对动脉粥样硬化患者脑血流动力学产生显著地的影响,而对不同的血管存在着不同程度的影响；（4）对于颈动脉狭窄率<90%的患者，颈部推拿对Willis环的血流动力学影响无统计学差异。结论：对于存在颈动脉粥样硬化，尤其是明显存在粥样硬化斑块的患者，最好避免进行颈部推拿手法操作。