磁共振成像技术应用于颞下颌关节紊乱病的评价

目的:通过各种MRI扫描序列比较,选择颞下颌关节紊乱病(temporomandibulardisorder,TMD)的最佳检查方法。方法:对13例患者,采用PHILIPS公司的GyroscanIntera型超导磁共振成像系统,磁场强度1.5T,选择11cm双侧表面线圈,9例采用双侧对比成像,4例单侧成像,共22侧。扫描闭口矢状位的自旋回波(SE)T1WI,快速自旋回波(FSE)T2WI,质子密度(PDW)及各种快速梯度回波(FastFieldEcho,FFE)T1W和T2W序列;冠状位扫描T1W和张口矢状位T1W。结果:各种扫描序列均可以显示颞下颌关节(TMJ)的基本解剖结构,从对比度、空间分辨率、信噪比和扫描时间几方面评价,FFE序列在缩短扫描时间的同时保持了一定的信噪比,优于常规SE序列,3D/FFE序列分辨率高,对关节盘、软骨显示好,并能在任意方向多平面重建,可进行精确的体积测量。结论:FFE序列优于常规SE序列,3D/FFE序列更适合于TMJ的检查。

Magnetic resonance imaging techniques in the evaluation of patients with temporomandibular disorders

AIM:To select the best method in the examination of temporomandibular joint (TMJ) by comparing various magnetic resonance(MR) scanning sequences. METHODS: MR imaging(MRI) was performed in 13 patients,total 22 TMJs, (9 cases bilateral,4 cases unilateral) on a 1.5 Tesla scanner (Gyroscan Intera, Philips) with the use of 11 cm surface coil as receivers.The MR protocol consisted of coronal oblique closed mouth T1 weighted and sagittal obliqueopen mouth T1W,and sagittal oblique closed mouth T1W spin echo (SE) images, Fast SE T2W images,PDW and various fast field echo (FFE) sequence T1W and T2W.RESULTS:The basic anatomical structure of TMJ could be displayed in any given sequence, but in the context of contrast, special resolution, S/N and scanning time, the FFE sequence was others in reducing scanning time and maintaining definite S/N,and with higher resolution and better articular disc and cartilage imaging in 3D/FFE in which the multiple plane reconstruction could be done at any given direction, 3D/FFE provided as the possibility of accurate mesurement of volume.CONCLUSION:FFE sequence is superior to routine SE and 3D/FFE is the most suitable to TMJ examination.