原发性中枢神经系统淋巴瘤MRI影像特征及误诊分析

MRI Features and Misdiagnosis of Primary Central Nervous System Lymphoma

目的探讨原发性中枢神经系统淋巴瘤(PCNSL)的磁共振成像(MRI)影像特征及误诊原因。方法选取2020年7月至2023年2月20例PCNSL患者,其中10例误诊,通过分析误诊、未误诊患者的MRI影像学资料,探讨PCNSL患者易误诊的影像学原因。结果本组头痛15例、肢体无力11例、视力视野受损7例、头晕6例。20例共检出30个病灶,位于浅部脑组织19个,深部脑组织7个,脑室内4个;单发病灶14例,多发病灶6例;合并坏死6例。10例首诊误诊者纳入误诊组,误诊为转移瘤5例、脑胶质瘤5例。误诊时间10 d~2个月。诊断正确组和误诊组在多发病灶、出血、合并坏死方面比较差异有统计学意义(P<0.05)。后经立体定向活检手术对MRI增强扫描明显增强部位取材行病理检查后,确诊弥漫大B细胞型淋巴瘤,予大剂量甲氨蝶呤联合放疗。随访1年,病情稳定,无死亡病例。结论接诊PCNSL患者时,当MRI增强扫描未发现典型征象时,易误诊颅内其他疾病;颅内占位性多发病灶、出血、合并坏死是PCNSL影像学误诊的因素,仔细观察、认真鉴别,必要时多学科协作会诊并及早行手术病理检查有利于降低误诊率。

Objective To investigate the MRI features of primary central nervous system lymphoma(PCNSL)and the causes of misdiagnosis.Methods From July 2020 to February 2023,20 patients with PCNSL were selected,10 of whom were misdiagnosed.The MRI data of patients with and without misdiagnosis were analyzed to explore the imaging causes of misdiagnosis of PCNSL patients.Results There was headache in 15 patients,limb weakness in 11 patients,visual impairment in 7 patients and dizziness in 6 patients.A total of 30 lesions were detected in 20 patients,including 19 that were located in superficial brain tissue,7 in deep brain tissue,and 4 in the ventricle.There were 14 cases of single lesions and 6 cases of multiple lesions.There were 6 cases with necrosis.Ten patients of initial misdiagnosis were included in the misdiagnosis group,including 5 patients with metastatic tumor and 5 patients with brain glioma.The misdiagnosis lasted 10 d-2 months.There were significant differences in multiple lesions,hemorrhage and necrosis between correct diagnosis group and misdiagnosis group(P<0.05).After stereo-directional biopsy was performed on the sites significantly enhanced by the enhanced MRI scan for pathological examination,diffuse large B-cell lymphoma was confirmed.The patients were treated with high-dose methotrexate combined with radiotherapy.The patients were followed up for 1 year,showing stable condition,and no death was reported.Conclusion For PCNSL patients,when the MRI enhancement scan does not reveal typical signs,it is more likely to be misdiagnosed as other intracranial diseases.Intracranial space occupying multiple lesions,hemorrhage,and necrosis are the factors of imaging misdiagnosis of PCNSL.Careful observation and identification,multidisciplinary consultation and early pathologic examination when necessary are conducive to reducing the misdiagnosis rate.