腮腺肿块的MRI诊断

目的：研究腮腺肿块的MRI表现与诊断。方法：回顾性分析经手术及穿刺病理证实的25例腮腺肿块的MRI表现。结果：混合瘤ll例，血管瘤2例，脂肪瘤1例，淋巴乳头状囊腺瘤2例，转移瘤2例，乳头状腺瘤2例，粘液表皮样瘤1例，慢性腮腺炎4例。所有病例在MRI上均清楚显示病灶，包括病灶大小、形态、边界、周边浸润及颈部淋巴结增大等。大多数病灶表现为长T1长T2信号(20／25)，1例为等T1中长T2信号，1例为等长T1短T2信号。其中血管瘤和脂肪瘤具有特征性信号，分别为等短T1长T2信号和短T1中长T2信号。术前或穿刺前影像诊断良恶性正确20例，误诊5例。结论：MRI对腮腺肿块显示率为100％，大多数能作出良恶性鉴别诊断，少数具有典型信号可推断其组织来源。

Tumor of Parotid Gland:MR Imaging Diagnosis

Objective: To describe the MRI finds and evaluate the value of MRI in diagnosis of parotid gland tumors.Methods:The MRI characteristics of 25 cases of parotid gland tumors confirmed surgically and pathologically were reviewed retrospectively.Results:All lesions were found clearly,including the size,shape,boundary, adjacent invasion and neck lymphatic nodule.Twenty lesions showed low signal intensity on T1WI and high intensity on T2WI;one lesion was iso intensity on T1WI and slight high intensity on T2WI;one lesion was slight low intensity on T1WI and low intensity on T2WI.Angioma and lipomas had their symbolical signals and they were iso intensity or high intensity on T1WI; high intensity on T2WI and high intensity on T1WI; slight high intensity on T2WI,respectively. Twenty cases were diagnosed correctly and 5 cases mistaken in differentiating between benign and malignant.Conclusion:The positive rate of lesion in MRI is 100%.Most of them can be differentiated benign from malignant.We can even generalize their tissue origin in a few cases.