脑内原发性非霍奇金淋巴瘤MRI诊断与鉴别诊断

目的：分析脑内原发性非霍奇金淋巴瘤的MRI特点,提高本病的诊断与鉴别诊断。方法：回顾性分析20例经立体定位活检、手术及病理确诊的脑内原发性淋巴瘤的MRI表现。20例术前均行MRI平扫,其中19例行MRI增强扫描,1例行DWI检查。结果：20例患者中单发15例,多发5例,20例共发现病灶28个。幕上18例,小脑2例。幕上者病变多位于脑室周围深部脑组织,其中基底节9例,大脑半球6例,胼胝体3例。MRI平扫表现为等T1、T2信号者13例,稍长T1、稍长T2信号7例,1例DWI上表现为高信号。病灶边界清楚,多为不规则形、类圆形,2例为结节状。增强扫描病灶明显均匀强化13例,不均匀强化6例,11例表现为＂握拳状＂强化,13例见＂尖角征＂,9例患者出现＂缺口征＂。结论：脑内原发性非霍奇金淋巴瘤的MRI表现具有一定特征性,术前MRI检查有助于诊断及鉴别诊断,对临床治疗方案的制定具有重要意义。

MRI diagnosis and differential diagnosis of intracerebral primary non-Hodgkin lymphoma

Objective：To analyze the MRI features of primary intracerebral non-Hodgkin lymphoma （NHL）,in order to improve the accuracy of diagnosis and differential diagnosis.Methods：MRI findings of 20 cases with primary intracerebral NHL proved by surgery and stereotactic biopsy were retrospectively analyzed.MRI plain scans were performed in all patients and contrast-enhanced scans were performed in 19 patients,while only 1 patient had MR diffuse-weighted imaging （DWI）.Results：Of the 20 cases,single lesion was seen in 15 and multiple lesions in 5 cases,totally 28 lesions were assessed.The location of lesions included supratentorial region （18 cases） and infratentorial region （2 cases）.The supratentorial lesions were mainly deeply seated,located at paraventricular region including basal ganglia （9 cases）,cerebral hemisphere （6 cases） and corpus callosum （3 cases）.The lesions showed iso-intensity on T1WI and T2WI in 13 cases and slightly hypointensity on T1WI and slightly hyperintensity on T2WI in 7 cases,and showed high signal intensity in that patient having DWI.Most of the lesions were well-circumscribed,round or irregular in shape,2 patients had nodular lesions.After contrast administration,the lesions showed markedly homogeneous enhancement in 13 cases and heterogeneous enhancement in 6 cases.There were ＂fist clenching sign-＂ in 11 cases,＂angular sign＂ in 13 cases and ＂notch sign＂ in 9 cases after enhancement.Conclusion：Certain characteristic findings could be revealed on MRI in primary intracerebral NHL patients.Preoperative MRI is helpful for the diagnosis and differential diagnosis and plays an important role in treatment planning.