鼻咽部淋巴瘤的MR平扫及动态增强特征

Nasopharynx lymphoma:Features on conventional and dynamic contrast-enhanced MRI

目的探讨鼻咽部淋巴瘤(NPL)的MR平扫及动态增强表现和相关参数特征。方法回顾经病理证实的27例NPL患者的MR平扫及动态增强扫描,分析其MRI信号、时间-信号强度曲线(TIC)类型,并统计达峰时间(TTP)、增强峰值(EP)、最大对比增强率(MCER)数值;对不同TIC类型及不同病理类型的NPL的TTP、EP、MCER进行统计学比较。结果 27例NPL中,88.89%(24/27)信号较均匀,余11.11%(3/27)信号混杂,病变T1WI呈等或稍低信号,T2WI呈稍高信号;鼻咽两侧壁均受累者占88.89%(24/27),仅累及一侧壁者11.11%(3/27);51.85%(14/27)伴周围侵犯。增强后,70.37%(19/27)呈中度较均匀强化,29.63%(8/27)呈中度不均匀强化。21例(21/27,77.78%)TIC呈平台型,6例(6/27,22.22%)呈流入型。TTP值为(63.21±14.29)s,EP值为1161.82±64.04,MCER值为(113.47±28.52)%。结论 NPL的TIC类型及相关参数(TTP、EP、MCER)具有一定规律性,结合MRI平扫特点有助于准确诊断NPL。

Objective To explore the features of nasopharynx lymphoma （NPL） on conventional MRI, dynamic contrast-enhanced MRI and related parameters. Methods Conventional MR, dynamic contrast-enhanced MR imaging of 27 patients with NPL proved by pathology were retrospectively reviewed, MR signals, types of time signal-intensity curves （TIC）, time to peak （TTP）, enhancement peak （EP）, maximum contrast enhancement ratio （MCER） of each case were analyzed. Statistical analysis of the differences of TTP, EP, MCER among different TIC types and different pathological types were carried out. Results Among 27 cases, 88.89% （24/27） NPL showed homogeneous signal intensity, while 11.11% （3/27） showed heterogeneous signal intensity. Most cases showed isointensity or slightly hypointensity on T1WI, slightly hyperintensity on T2WI, 88.89% （24/27） with involvement of both side wall of the nasopharynx, 11.11%（3/27） with involvement of single side, 51.85%（14/27） lesions invading surrounding structures. Moderate and homogeneous enhancement was observed in 19 cases, while heterogeneous enhancement was observed in the other 8 cases. Platform type curve was found in 21 cases （21/27, 77.78%）, a uptrend type curve was found in 6 cases （6/27, 22.22%）. The average TTP was （63.21±14.29）s, EP was 1161.82±64.04 and MCER was （113.47±28.52）%. Conclusion TIC types and related parameters of NPL, such as TTP, EP and MCER reveal characteristic regularities. Conventional MRI combined with these parameters contribute to correct diagnosis.