腮腺间隙良性肿瘤的MRI诊断

目的探讨腮腺间隙常见良性肿瘤的影像特征及其诊断与鉴别诊断。方法良性肿瘤20例，包括多形性腺瘤13例、乳头状淋巴囊腺瘤3例、淋巴管瘤2例、血管瘤1例、脂肪瘤1例。经手术病理证实15例，穿刺活检证实4例，典型MR特征结合病史确诊1例。结果13例多形性腺瘤中有11例位于腮腺浅叶，2例位于深叶；9例表现为均匀等T1长T2信号．4例在T2WI上信号明显不均匀；静脉注射Gd—UIPA后3例瘤实质均匀强化，4例增强后明显不均匀强化。3例Warthin瘤中2例发生于一侧，1例累及双侧腮腺，在T1WI上呈低信号，T2WI上信号等于或低于正常腺实质，增强后无明显强化。2例淋巴管瘤呈明显长T1长T2信号，并有多房现象。1例血管瘤信号不均质，呈明显长T1长T2信号，静1脉注射Gd—DTPA后病变往往显著异常强化。1例脂肪瘤在T1WI及T2WI上均表现为明显高信号强度。结论运用MR成像研究腮腺间隙的良性肿瘤，有利于疾病的定位，有助于病变的诊断与鉴别诊断。

MRI diagnsis of benign tumor in parotid space

Objective To investigate the image character and diagnosis and differential diagnosis of benign tumors in parotid space.Methods 20 benign tumors were 13 pleomorphism tumors, 3 Warthin tumors, 2 lymphangiomas, 1 hemangioma and 1 liopmas. Surgery pathology and biopsy proved 19 cases. 1 case had typical MR signal intensity.Results 11 cases of 13 pleomorphism tumors located in shallow lobe of parotid,2 cases in deep lobe of parotid. 9 cases presented to equal T 1 and long T 2 signal intensity uniformly. 4 cases had unhomogeneous signal intensity on T 2WI. After intravenous injection Gd-DTPA, 3 cases in parenchyma displayed enhancement uniformly,4 cases enhanced unhomogeneous in evidence. 2 cases of 3 Warthin tumors took place in unilateral, 1 case was in double parotid. 3 Warthin tumors all presented low-intensity on T 1WI and low or equal to intensity of nomal parenchyma on T 2WI. There were no enhancement. 2 lymphangiomas displayed long T 1 and long T 2 signal intensity in evidence and many loculus in interior. 1 hemangioma displayed unhomogeneous signal intensity with long T 1 and long T 2 evidently. There was marked enhance with intravenous injection Gd-DTPA. 1 liopmas presented high signal intensity in T 1WI and T 2WI.Conclusion Studying benign tumor in parotid space with MRI is helpful to locate lesion and their diagnosis and differential diagnosis.