寰枢关节多层螺旋CT旋转功能位影像学观测

目的:通过测量分析正常寰枢关节在多层螺旋CT中立位及旋转功能位的各种影像征象,为临床准确诊断寰枢关节旋转半脱位提供量化标准。方法:对51例正常志愿者进行中立位、左右尽力旋转位扫描,观察测量寰齿前间隙(atlanto-dental interval,ADI),齿突侧块间隙(lateral atlanta-dental space,LADS),齿突侧块间距差值(VBLADS)及寰枢椎相对旋转角度(rotating angle of atlas on dentate,RAAD),分析比较各影像表现及解剖学特点。将51例正常志愿者分为年龄<45岁及年龄≥45岁两组,比较不同年龄段人群VBLADS及RAAD的变化及进行相关性分析。结果:51例正常志愿者通过三维重建软件显示中立位寰枢外侧关节基本对称,齿突侧块间隙不对称者40例,占78.4%.中立位齿突偏移角度范围为(3.22±0.89)°,尽力旋转位寰枢椎(atlanto-axial joint)外侧关节面呈旋转性关节面移位,相对旋转角度范围为(33.85±2.79)°。通过配对资料相关性分析得出在一定范围内寰枢椎相对旋转角度与VBLADS无相关性。<45岁及≥45岁尽力旋转位时寰枢椎相对旋转角度之间差异有统计学意义。结论:多层螺旋CT旋转功能位能清楚显示寰枢区的解剖结构及旋转功能,为诊断寰枢关节旋转半脱位提供理论依据。

MSCT imaging research on atlanto-axial joint in rotary functional position

Objective:To provide quantitative foundation for the diagnosis of atlanto-axial rotatory subluxation by analyzing the various imaging features of normal atlanto-axial joints in neutral position and rotary functional position on the MSCT images.Methods:Forty-one normal volunteers were examined by CT on the atlanto-axial joint in neutral position and rotary functional position. By the observation and measurement of atlanto-dental interval(ADI),lateral atlanta-dental space(LADS),VBLADS and rotating angle of atlas on dentate (RAAD),the imaging manifestations and anatomical characteristics were analyzed and compared. In order to compare VBLADS and RAAD and make a correlation analysis between different age groups,51 normal volunteers were divided into two groups:age younger than 45 years old group and age older than or equal to 45 years old group.Results: The dens in neutral position deviated in an angle range of (3.22±0.89)°. The articular facets of lateral atlantoaxial joint in rotary functional position had rotatory displacement and the range of the relative rotation angle was(33.85±2.79)°. Through the correlation analysis of matching data,it could be concluded that there was no correlation between atlantoaxial relative rotation angle and VBLADS within a certain range. There were statistically differences of atlantoaxial relative rotation angle in rotary functional position between two groups.Conclusion:MSCT imaging in rotary functional position can clearly show the anatomical structure and rotation function of a normal atlanto-axial joint,so as to provide a theoretical basis for the diagnosis of atlanto axial rotatory subluxation.