颅内原发恶性淋巴瘤的MRI表现

目的:总结颅内原发恶性淋巴瘤的MRI表现,分析术前误诊的原因,以提高诊断的准确度。方法:回顾性分析18例经手术病理证实的原发性颅内淋巴瘤(弥漫大B细胞型)的MRI平扫、增强及弥散加权成像(DWI)的特征性表现。结果:单发病灶15例,多发病灶3例。其中脑干1例,小颅蚓部1例,大颅半球14例,基底节区1例,右侧丘颅1例。术前误诊4例(均诊断为颅内胶质瘤)。18例均为弥漫大B细胞型非霍奇金淋巴瘤。18例病变均表现为占位性肿块,T1WI呈低、等信号;T2WI呈等、稍高信号;行马根维显增强扫描,无坏死病灶均呈较均匀显著强化,伴有坏死时,坏死区无强化。16例瘤周中度水肿,2例瘤周重度水肿。10例行DWI序列扫描病变呈均匀高信号表现。结论:原发性颅内淋巴瘤的MRI表现有一定的特征性。MRI平扫、增强扫描及弥散加权成像(DWI)特点综合分析可提高对本病诊断率。弥散加权成像(DWI)的特点对诊断与鉴别诊断具有一定的参考价值。

MRI Characterization of Intracranial Primary Malignant Lymphoma

To study the magnetic resonance imaging（MRI） characterizations of intracranial primary malignant lymphoma, and analyze the causes of misdiagnosis before surgery in order to improve diagnostic accuracy, e The MRI characteristics of normal scan, enhanced scan and diffusion weighted imaging（DWI） of 18 cases with pathologically confirmed primary intracranial lymphoma（diffuse large B cell type） were analyzed retrospectively. Results Fifteen cases were of single lesions, and 3 cases were of multiple lesions, of which 1 case in brain stem, 1 case in small cranial vermis, 14 cases in large cranial hemisphere, 1 case in basal ganglia, and 1 case in right mound skull. Four cases were misdiagnosed （all were diagnosed as glioma in brain）. Pathological results of 18 cases were diffuse large B-cell non-Hodgkin＇s lymphoma. Eighteen cases of space occupying lesions appeared as mass, T1WI showed low or equal signal; T2WI showed equal or a little higher signal. After magnetic enhanced scanning, non-necrosis niduses were all characterized as even significantly enhanced, but for the nidus following with necrosis, the area of which was not enhanced. There were 16 cases with moderate peripheral edema, and 2 cases of severe peripheral edema. The DWI array scan results of 10 cases showed the nidus presented high signal performance. MRI performance of intracranial primary malignant lymphoma has a regular pattern. The comprehensive analysis of normal scan, enhanced scan and DWI can improve the diagnosis accuracy. The features of DWI possess a certain reference value to diagnosis and differential diagnosis.