原发性脑淋巴瘤的CT及MRI诊断

CT and MRI diagnosis of primary brain lymphoma

目的探讨原发性脑淋巴瘤的CT及MRI影像学特征。方法对20例经手术病理证实的脑淋巴瘤患者的CT及MRI影像学表现进行回顾性分析。结果20例脑淋巴瘤患者17例单发,3例多发,共有24个病灶。其中,CT及MRI图像有以下特点:a)瘤灶多为单发,幕上多见,多为圆形或不规则形;b)CT平扫多呈等或略高密度,无钙化,MRT1WI呈略低或等信号,T2WI呈等或略高信号,瘤周水肿及占位效应相对较轻;c)CT及MRI增强扫描病灶多呈均匀明显强化,亦可不均匀呈环形或花瓣样强化。结论脑原发性淋巴瘤影像表现缺少特征性,确诊主要依靠病理检查。

Objective To discuss the CT and MRI findings of primary brain lymphoma. Methods Twenty patients with surgically and pathologically proved primary brain lymphoma underwent CT and MRI scans without and with contrast enhancement after onset of clinical symptoms. CT and MRI findings in all patients were analyzed retrospectively. Results 24 lesions of 20 patients were detected - out by CT and MRI, who comprised 17 single - and 3 multiple lesions. On CT and MR images, the most tumoral lesions were single foci on supratentoria and presented as round or irregular shape. CT plain scans showed that the most lesions were isodense or slightly hyperdense without calcification. On MR T1W images, the most lesions were slight hypolntensity or isointensity while on T2W images, the most lesions were isointensity or slight hyperintensity, peritumoral edema and space - occupying effect were relatively mild. On enhanced CT and MRI images, the most lesions were homogeneous emhancement but partial lesions were heterogeneously circular or petaling enhancement. Conclusion Primary brain lymphoma lacks imaging features so that the definite diagnosis mainly depend on the pathology.