腮腺肿瘤的MRI诊断

目的:通过回顾性分析肿瘤形状、边界、T1WI和T2WI信号强度、均匀性、增强效果等形态学征象,总结腮腺肿瘤的MRI表现,探讨腮腺肿瘤的诊断与鉴别诊断价值.方法:收集经手术证实的24例腮腺肿瘤的MRI资料,与病理改变进行对照分析.MR平扫采用T1WI、T2WI扫描,部分同时行平扫和增强扫描.结果:腮腺肿瘤大多位于腮腺浅叶(14/24),良性肿瘤以多形性腺瘤居多(13/19),MRI表现为境界清楚、信号均匀的肿块.恶性肿瘤以粘液表皮样癌较多(4/5),MRI多显示为境界不清、信号不均匀的肿块.转移癌以鼻咽部来源多见(1/5).结论:腮腺肿瘤在MRI表现上有其各自特点,对绝大多数病例进行定性诊断是可能的.

MRI Diagnosis of Parotid Tumour

Objective: To summarize MR manifestations of parotid tumour to investigate their value of diagnosis and differential diagnosis.MR findings of parotid tumour including shape,margin,signal intensity on T1WI and T2WI,homogeneity of the signal,enhancement were analyzed retrospectively in this study.Method: In total 24 cases of parotid tumours proved by surgery were enrolled.MRI manifestations were comparatively studied with pathological findings.T1WI and T2WI sequence were used in noncontrast scan,while both non-contrast and enhanced scan were performed in 20 lesions out of 24.Result: Most tumours of parotid gland were located in the shallow leaves(14/24).Most benign tumours were mixed tumour(13/19) which manifested as masses with clear borders and even signal in MRI.Mucoepidermoid carcinomas constituted the majority in malignant tumours of parotid gland,which showed as masses with obscure bounderies and various signal.Most metastases originated from nasopharyngeal carcinoma.Conclusion: There are certain characteristics of parotid tumours on MR images,and these are helpful in determing the histological nature of the tumour.