【作者】 李彦；

【导师】 李传亭； 杨贞振；

【作者基本信息】 山东大学 ， 影像医学与核医学， 2010， 硕士

【摘要】 目的：MRI具有良好的组织对比分辨力,能清晰的显示腮腺肿瘤本身及其周围的软组织,对于腮腺肿瘤的诊断具有非常重要的作用,已成为目前检查、诊断腮腺肿瘤理想的手段。本文探讨3 T MR三维稳态进动快速成像(3D-FIESTA)序列显示腮腺良性肿瘤及其与腮腺内面神经和腮腺导管关系的价值。方法：选取未经手术的腮腺肿瘤患者31例,所有患者均经手术病理证实,其中男14例,女17例；年龄15～75岁,平均45岁；病史从3个月至10年,多表现为腮腺区发现无痛性肿块。所有患者均经手术病理证实,31例腮腺肿瘤均为良性,包括：多形性腺瘤19例,腺淋巴瘤9例,嗜酸性细胞腺瘤1例,基底细胞腺瘤1例,鳃裂囊肿1例。应用3.0T超导型磁共振扫描仪(美国GE Signa EXCITE HD),采用头部八通道线圈。扫描序列包括常规MR序列T1FLAIR、T2WI及3D-FIESTA序列。所有病例均行T1加权流动衰减反转恢复序列(T1FLAIR) (TR 2580 ms, TE 23ms, TI 860ms)、快速SE序列(FSE)T2WI(TR 4600 ms TE 110 ms); FOV 240 mm×240 mm,层厚4.0 mm,层间距0.5 m,行横断和冠状面扫描。3D-FIESTA序列扫描参数为TR 4.9 ms,有效回波时间(TEeff) 1.5 ms,反转角55°,ROI 18 cm×18 cm～20 cm×20 cm,矩阵512×320,行横断面无层间隔扫描,层厚1.0mm。两位影像专家在不知病理结果的情况下独立对31例患者的影像资料进行诊断并对T1FLAIR、T2WI、3D-FIESTA序列对腮腺肿瘤与腮腺导管、面神经及其分支的位置关系的显示情况进行对比分析,同时观察分析不同类型腮腺肿瘤的位置、形态、边界、信号强度特点。采用AW sdc 4.3工作站进行多平面图像重建,腮腺内面神经3D-FIESTA序列呈低信号,腮腺内导管呈高信号。常规序列和3D-FIESTA序列显示结果与手术所见和病理结果进行对照。结果：不同类型的腮腺良性肿瘤3T MRI表现具有一定的各自特点。31例腮腺肿瘤在T,FLAIR主要显示为低信号,在T2WI上为高信号,其显示结果分别为30／31、28/31; 3D-FIESTA序列上则根据腮腺肿瘤类型的不同表现为低信号(14／31)或高信号(17／31)为主。腮腺内面神经主要分支在T1FLAIR、T2WI及3D-FIESTA序列图像均显示为线样低信号结构,T1FLAIR、T2WI对面神经主干的显示率分别为77.4%、74.2%；而3D-FIESTA对面神经主干、颈面支、颞面支的显示率分别为100%、96.8%、93.6%。腮腺导管及其主要分支在T1FLAIR上呈线条状低信号,T2WI及3D-FIESTA序列图像显示为条状高信号结构,其显示率分别为64.5%、80.7%、100%。与术中显示其走行和移位情况相对照,面神经主干、颈面支、颞面支的显示正确率分别为100%、96.8%、93.6%。腮腺主导管27例与3D-FIESTA序列的显示情况相一致,显示正确率为87.1%；有4例因肿瘤推压移位,手术解剖不到位而未显示。结论：3 T MR 3D-FIESTA序列可以正确显示腮腺内面神经和腮腺导管及其与腮腺肿瘤的关系,对腮腺肿瘤手术计划的制定有重要的应用价值。更多还原

【Abstract】 ObjectiveMR imaging has high tissue resolution and could display parotid neoplasms itself and peripheral tissues.It plays an important role in the diagnosis of parotid neoplasms and has become an ideal tool in parotid imaging.To investigate the usefulness of 3T MR imaging 3D-FIESTA in evaluation intraparotid components of the facial nerve and parotid duct, and compared with surgical findings.Method31 patients (14 males and 17 females,15-75years old, mean age 45 years) with a diagnosis of parotid neoplasm were included in the study. Their medical history was showed from 3 months to 10 years, and mostly manifested as painless mass in the parotid gland region.All lesions were confirmed benign parotid tumours:19 pleomorphic adenomas,9 Warthin’s tumours, one acidophile adenoma, one basal cell adenoma, and one branchial cleft cyst.All examinations were performed on GE 3.0 MRI scanner (General Electric medical systems, USA) with 8-channel array coil. The MR scanning sequences included routine sequences and 3D-FIESTA sequence. T1-weighted fluid-attenuated inversion recovery sequence (TR 2580 ms, TE 23 ms, TI 860 ms), fast SE T2-weighted sequence (TR 4600 ms, TE 110 ms); FOV 240 mm×240 mm, section thickness 4.0 mm, intersection gap 0.5 mm, carrying out in the axial and coronal planes. The following parameters were used in 3D-FIESTA sequence:TR 4.9 ms, Effective echo time (TEeff) 1.5 ms, anti-angle 55°, ROI 18 cm×18 cm～20 cm×20 cm, imaging matrix 512×320, an axial plane and no intersection gap, section thickness 1.0 mm.Two radiologists independently diagnosed image data of 31 patients without knowledge of the surgical or pathological results. The parotid tumors, parotid duct, facial nerve and its branches and its temporofacial and cervicofacial divisions were evaluated on the T1-weighted fluid-attenuated inversion recovery sequence, T2-weighted and 3D-FIESTA images. Different types of parotid gland tumor’s location, shape, borders, signal intensity characteristics were analyzed simultaneously.Postprocessed multiplanar images were obtained with AW sdc 4.3 workstation. Parotid ducts and facial nerves and tumors were identified on these images. Facial nerves in parotid appeared as linear structures in hypo-intensity. Parotid ducts appeared as structures in hypo-intensity. The relationship of the tumors to the facial nerves and Parotid ducts was confirmed at surgery.ResultDifferent types of parotid benign tumors have their characteristics in 3T MR imaging.31 cases of parotid benign tumors mainly showed hypo-intensity on T1FLAIR, hyper-intensity on T2WI, the indication of these were 30/31、28/31; but on 3D-FIESTA sequence, they appeared hypo-intensity (14/31) or high intensity(17/31) according with different types.Facial nerves in parotid appeared as linear structures in hypo-intensity. The indication of the main trunks were 77.4%、74.2% on conventional sequence, but on 3D-FIESTA sequence, the main trunks and cervicofacial and temporofacial divisions of the facial nerves were 100%、96.8%、93.6%.Parotid ducts appeared as structures in hypo-intensity on T1FLAIR and hyper-intensity in multiplanar images (64.5%、80.7%、100%).Compared with surgical result, the main trunks、cervicofacial and temporofacial divisions of the facial nerve was correctly diagnosed in 100%、96.8%、93.6%.27 cases of parotid duct were concording with 3D-FIESTA sequence(87.1%), 4 cases were not shown because they were not anatomized after being shift.Conclusion3 T MR 3D-FIESTA imaging could depict the extracranial facial nerve and the parotid duct in the parotid gland, and is useful for preoperative evaluation of parotid gland tumors.更多还原