摘要
目的分析不典型原发性中枢神经系统淋巴瘤(PCNSL)磁共振成像(MRI)表现及其误诊原因,探讨常规MRI征象联合最小表观弥散系数值(ADCmin)及磁共振波谱(MRS)成像特征对不典型PCNSL的诊断与鉴别价值。方法收集2015年1月至2020年12月连云港市第二人民医院与徐州医科大学附属医院经过临床及病理证实的15例不典型PCNSL患者的临床及影像资料,所有病例均行MRI平扫、增强及扩散加权成像(DWI)检查,3例行MRS检查。观察分析15例不典型PCNSL的常规MRI特征、DWI信号特点及MRS成像特征,对不典型PCNSL的MRI表现及误诊原因进行归纳分析;测量并比较肿瘤实质ADCmin,近、远侧瘤周平均表观弥散系数(ADC)值及对侧正常脑白质平均ADC值,并且探寻不同区域ADC值的变化规律。结果15例PCNSL中,14例单发,1例多发,共21个病灶。(1)单发病灶位于少见部位:脑表浅部位4例,桥臂1例,小脑半球1例,鞍上1例,第三脑室1例。(2)不典型MRI表现:囊变、坏死病灶5个(5/21),同时伴有出血1个(1/21);DWI呈等信号病灶3个,ADC伪彩图呈等低信号;环形强化病灶5个,片状强化病灶3个。(3)多中心生长方式:多发1例,共7个病灶,位于右侧丘脑、基底节及放射冠,呈多发结节样及环形强化。MRS检查示:3例单发病灶均见胆碱复合物(Cho)峰升高,肌酸(Cr)峰降低,乙酰天门冬氨酸(NAA)峰明显降低,2例可见高耸脂质(Lip)峰为第一高峰。肿瘤实质ADCmin,近、远侧瘤周平均ADC值及对侧脑白质的平均ADC值变化趋势呈先升后降抛物线型,分别为:(0.54±0.06)×10^(-3) mm^(2)/s、(1.55±0.10)×10^(-3) mm^(2)/s、(1.45±0.09)×10^(-3) mm^(2)/s、(0.85±0.03)×10^(-3) mm^(2)/s,总体差异有统计学意义(F=630.570,P<0.001),两两比较差异有统计学意义(均P<0.05)。结论非典型PCNSL易误诊,常规MRI特征分析联合DWI、MRS成像特征及对比肿瘤不同区域ADC值的差异性,有助于对PCNSL的诊断与鉴别,有望提高诊断准确性。
Objective To observe and analyze the atypical magnetic resonance imaging(MRI)findings and misdiagnosis reasons of primary central nervous system lymphoma(PCNSL),and to explore the value of conventional MRI signs combined with minimum apparent diffusion coefficient value(ADCmin)and imaging features of magnetic resonance spectroscopy(MRS)in the diagnosis and differentiation of atypical PCNSL.Methods The clinical and imaging data of 15 patients with atypical PCNSL confirmed by clinical and pathological findings from Lianyungang Second People′s Hospital and the Affiliated Hospital of Xuzhou Medical University from January 2015 to December 2020 was collected.All cases were examined by plain MRI,enhanced and diffusion weighted imaging(DWI),and 3 cases were examined by MRS.The conventional MRI features,DWI signal features and MRS imaging features of 15 cases of atypical PCNSL were observed and analyzed,and the MRI findings of atypical PCNSL and the causes of misdiagnosis were summarized and analyzed.The ADCmin of tumor parenchyma,the mean ADC values of proximal peritumor,distal peritumor and contralateral white matter were detected and compared to explore the variation rules of ADC values in different regions.Results Of the 15 cases of PCNSL,14 cases were single and 1 case was multiple,with a total of 21 lesions.(1)Single lesions in rare sites:4 cases in the superficial part of the brain,1 case in the bridge arm,1 case in the cerebellar hemisphere,1 case in the suprasellar saddle,and 1 case in the third ventricle.(2)Atypical MRI findings:cystic degeneration or necrosis in 5 lesions(5/21),accompanied by hemorrhage in 1 lesion(1/21);There were 3 isosensitive lesions on DWI,and isosensitive lesions on ADC false color images.There were 5 ring enhancement lesions and 3 sheet enhancement lesions.(3)Multi-center growth pattern:1 case with a total of 7 lesions,located in the right thalamus,basal ganglia and corona radiata,showing multiple nodules and ring enhancement.1H-MRS examination showed that choline(Cho)peak increased,creatine(Cr)peak decreased,N-acetyl aspartate(NAA)peak decreased,and obvious Lip peak appeared in all the 3 cases with single lesions.2 cases showed high Lip peak as the first peak.The ADCmin values of tumor parenchyma,proximal peritumor,distal peritumor and contralateral white matter showed a parabola pattern of first rise and then decline,as follows:(0.54±0.06)×10^(-3) mm^(2)/s,(1.55±0.10)×10^(-3) mm^(2)/s,(1.45±0.09)×10^(-3) mm^(2)/s,(0.85±0.03)×10^(-3) mm^(2)/s,overall difference was statistically significant(F=630.570,P<0.001).The pairwise comparison was statistically significant(all P<0.05).Conclusions Atypical PCNSL is easy to be misdiagnosed.Conventional MRI feature analysis combined with DWI and MRS imaging features and comparison of ADC values in different tumor areas are helpful for the diagnosis and differentiation of PCNSL and are expected to improve diagnostic accuracy.
作者
耿磊
孙毅
王锐
万金鑫
杨伏猛
汪秀玲
徐凯
Geng Lei;Sun Yi;Wang Rui;Wan Jinxin;Yang Fumeng;Wang Xiuling;Xu Kai(Department of Medical Imaging,the Second People′s Hospital of Lianyungang(Lianyungang Cancer Hospital),Lianyungang 222000,China;Department of Laboratory,the Second People′s Hospital of Lianyungang(Lianyungang Cancer Hospital),Lianyungang 222000,China;Department of Medical Imaging,the Affiliated Hospital of Xuzhou Medical University,Xuzhou 221002,China)
出处
《中国医师杂志》
CAS
2022年第11期1649-1654,1660,共7页
Journal of Chinese Physician
基金
连云港市卫生健康面上科技项目(202219)
连云港市"十四五"花果山·科教强医工程资助项目(52310656)
江苏大学临床医学科技发展基金(JLY20180158)
连云港市第二人民医院中青年人才成长基金科研课题计划(TQ201906)
江苏省卫生健康委2020年度医学科研项目(Z2020144)。
关键词
中枢神经系统肿瘤
淋巴瘤
非霍奇金
弥散磁共振成像
磁共振波谱学
Central nervous system neoplasms
Lymphoma,non-Hodgkin
Diffusion magnetic resonance imaging
Magnetic resonance spectroscopy
