颅脑原发性淋巴瘤的MRI特征分析

Analysis of MRI characteristics of primary cranial lymphoma

目的探讨颅脑原发性淋巴瘤(PCL)的MRI影像特征表现。方法回顾性分析2010年12月~2016年12月金州区第一人民医院收治的13例被临床或手术病理证实的颅脑原发性淋巴瘤患者的MRI影像特征,包括平扫和增强扫描,其中5例加做MRS检查,2例补充3D-ASL。结果 13例中单发10例,多发3例,其中1例原发淋巴瘤并发腰椎管淋巴瘤,共检出17个病灶,病灶均呈实性包块样病灶,T1WI包块呈稍低信号,T2WI以等、稍高信号为主,其中3例包块内见囊变坏死区,DWI以明显高信号为主,部分病灶稍高信号影,重建ADC图明显低信号,增强后病灶均中等或明显增强。5例MRS表现为Cho明显升高,Cr及NAA明显降低,出现高耸的Lip峰,2例可见Lac峰,3D-ASL表现为相对脑血流量(CBF)下降,低灌注改变。结论常规磁共振扫描与弥散加权成像、增强扫描及特殊功能成像(MRS、3D-ASL)联合应用可以提高MRI对PCL的诊断准确性,为临床治疗方案的制定提供一定的信息和依据。

Objective To investigate the MRI features of primary cranial lymphoma（PCL）. Methods The MRI features of 13 cases of primary cranial lymphoma confirmed by clinical or surgical pathology treated in the First People′s Hospital of Jinzhou District from December 2010 to December 2016 were retrospectively analyzed, including plain and enhanced scan, of which 5 cases underwent extra magnetic resonance spectroscopy（MRS） and 2 cases accepted 3 D-arterial spin labeling（3 D-ASL）. Results Among 13 cases, there were 10 solitary cases and 3 multiple cases, of which 1 cases of primary lymphoma were complicated with lumbar spinal canal lymphoma, and altogether 17 lesions were detected. All the lesions were solid mass-like lesions. The T1 WI mass showed a slight low signal, and the T2 WI showed mainly high signal. The cystic degeneration dead zone was seen in 3 cases, and DWI showed mainly high signal with high signal shadow of partial lesions. Reconstructed analog-to-digital converter（ADC） images showed significant low signal and enhanced lesions were moderately or markedly enhanced. 5 cases of MRS showed significantly increased choline（Cho） level, significantly decreased Cr and NAA, with the emergence of high Lip peak. The Lac peak was seen in 2 cases. 3 D-ASL showed decreasing relative cerebral blood flow（CBF） and low perfusion change. Conclusion The combination of application of conventional magnetic resonance imaging（MRI） with diffusion weighted imaging, enhanced scan and special functional imaging（MRS, 3 D-ASL） can improve the accuracy of MRI in diagnosis of PCL, and provide certain information and basis for the formulation of clinical treatment plan.