MR涎管造影临床研究及应用

目的 评价MR涎管造影的各种序列技术和临床应用。方法 依次采用短时反转恢复序列(STIR)、重T2加权快速自旋回波序列(重T2WIFSE)、单次激发快速自旋回波序列(SSFSE)，厚层扫描，快速采集，于服用维生素C(VitC)前后分别扫描。检查了30例，其中13例为志愿者，17例为可疑涎管异常者。结果 3种序列均能显示正常腮腺和颌下腺主导管。13例志愿者STIR序列均能清晰显示涎管1级和2级分支，2例能显示管径约为0．8mm的末梢分支；重T2WIFSE序列可清晰显示13例志愿者1级分支、10例2级分支；SSFSE序列可显示10例涎管1级分支、6例2级分支。STIR序列能清晰显示患者主导管和涎管1、2级分支；重T2WIFSE序列清晰显示患者12例涎管1级、8例2级分支；SSFSE序列清晰显示患者10例1级分支、4例2级分支。17例可疑异常者，腺体炎症7例，急性炎症主导管稍增粗，末梢导管呈点、球状扩张；颌下腺癌1例，导管受压移位，呈截断状改变；良性肿瘤7例，涎管受压移位，无中断；干燥综合征及涎腺病各1例，涎管未见明显异常。16例患者含服VitC0．2g后5min重复扫描，涎管显示较前增粗。结论 MR涎管造影能清晰显示腮腺和颌下腺导管系统，其中STIR序列能清晰显示导管2级分支，是1种显示涎管的非侵袭性方法，含服VitC后可使唾液分泌增多，从而使涎管显示率增加，具有较高的临床实用价值。

Comparative study and application of MR sialography using different pulse sequences

Objective To evaluate the accuracy of MR sialography in demonstrating the main salivary duct systems by using a series of pulse sequences and stimulation of salivation by vitamin C. Methods MR sialography was prospectively performed with STIR, heavily T2 weighted FSE, and SS FSE sequences in 17 patients suspected with salivary duct abnormalities and 13 volunteers, respectively, and MR sialography was further performed in 16 patients after vitamin C stimulation. The results of the above three sequences were compared with each other . Results The main salivary gland duct was depicted in all cases by any of the mentioned sequence. The STIR images were significantly superior to SS FSE and heavily T2 weighted FSE images for demonstrating the salivary duct system, followed by heavily T2 weighted FSE images. On STIR images,first- and second- order intraglandular branches were clearly depicted in all cases, and the thinnest branches were about 0. 8 mm. On heavily T2 weighted FSE images, the first-order and the second-order intraglandular branches were delineated in 25 of 30 and 18 of 30 cases, respectively. But on SS FSE images, only 20 of 30 first-order and 10 of 30 second-order intraglandular branches could be detected. MR sialography with vitamin C stimulation revealed the good visualization of the salivary duct system, and the ducts became wider than before. In 7 cases with acute sialoadenitis, the main duct became slightly wider and the distal ducts were dilated; In 7 cases with benign tumor,the ducts were displaced but remained continuous; The duct in one patient with submandibular gland cancer showed destruction and discontinuity. The ducts of one patient with Sjogren syndrome and one with sialidosis displayed normal. Conclusion MR sialography with evoked salivation is noninvasive and allows delineation of both normal and abnormal parotid and submandibular gland duct systems, and the images are especially better on STIR sequence.