张口位MRI动态研究在诊断颞下颌关节盘前移位中的应用

目的：探讨颞下颌关节张口位磁共振动态成像在颞下颌关节盘前移位中的诊断价值。方法：对30例有颞下颌关节疼痛或弹响MRI患者60侧颞下颌关节行常规MRI静态扫描，并用快速自旋回波扫描获得开口度为0．5cm的图像，依次进行到患者达到最大开口位。然后采用模拟动态观察。分别由两名专科医师对动态扫描和常规静态扫描时关节盘移位进行诊断，并比较诊断结果。结果：静态MRI检查中关节盘可复性前移位21侧，关节盘不可复性前移位18侧，关节盘侧向移位2例，位置正常19例。动态MRI检查中关节盘可复性前移位23侧，关节盘不可复性前移位19侧，位置正常18例。结论：张口位动态MRI联合静态MRI观察对髁突、关节盘运动功能的评价非常重要，对区别可复性与不可复性关节盘前移位具有重要作用。

The application of open-mouth MR dynamic study in the diagnosis of anterior disk displacement of temporal-mandibular joint.

Objective：To evaluate the value of dynamic magnetic resonance imaging of temporomandibular joint in the diagnosis of anterior disc displacement of TMJ. Method：30 patient （60 TMJs） with temporomandibular joint pain or clicking underwent regular static magnetic resonance scan and the imagings were obtained when the mouth opening was 0.5 mm and maximum using TSE. The disc displacement was diagnosed by two specialists according to dynamic or static magnetic reso- nance imaging and the diagnostic result were compared. Result：Static magnetic resonance imaging showed 21 TMJs with an- terior disc displacement with reduction,18 TMJs with anterior disc displacement without reduction,2 TMJs with lateral disc displacement,19 cases with normal position. However,when using dynamic magnetic resonance imaging as the examining method,23 TMJs with anterior disc displacement with reduction,19 TMJs with anterior disc displacement without reduction,18 cases with normal position. Conclusion：Using dynamic observation to evaluate the motor function of the disc and the condyle is very important, which plays an important role in the differentiation of anterior disc displacement with or without reduction.