Sutherland Tom, Yap Kelvin, Liew Elaine, Tartaglia Con, Pang Mai, Trost Nicholas
MRI Department, St Vincents Hospital, Fitzroy, Victoria, Australia.
J Med Imaging Radiat Oncol. 2012 Jun;56(3):295-301. doi: 10.1111/j.1754-9485.2012.02366.x. Epub 2012 Apr 10.
To define the features of primary central nervous system lymphoma (PCNSL) on MRI in immunocompetent patients.
A retrospective review of the authors' institutional database was performed to identify histologically proven cases of PCNSL. Images were retrieved and reviewed with respect to location, lesion number, size, signal intensity, enhancement characteristics, oedema and necrosis.
Thirty-one cases of histologically proven PCNSL had available imaging. One patient was excluded due to immunosuppression. Of the 30 remaining cases, the average age was 65.5 years, and males and females were equally represented. A total of 68 lesions (average of 2.5 per patient) were identified. With diffusion-weighted imaging, all but two had restricted diffusion (40.3% mild and 55.6% marked) and all but one had enhancement (51.5% homogeneous, 42.6% heterogeneous and ring 4.4%). Most lesions were isointense to grey matter (75.8% on T2-weighted image (WI) and 82.5% on T1-WI). Oedema was mild in 43.4% and marked in 55.2%. Necrosis was seen in only five lesions (7.4%). On a per patient basis, 50% had bilateral lesions and 96.7% had lesions contacting a cerebrospinal fluid (CSF) surface. 16.7% of patients had posterior fossa involvement and 30% had lesions in the basal ganglia or thalami.
The vast majority of cases of PCNSL in immunocompetent patients have lesions contacting a CSF surface, enhancement and restricted diffusion with no necrosis. These features should alert radiologists to the diagnosis of PCNSL.
明确免疫功能正常患者原发性中枢神经系统淋巴瘤（PCNSL）的MRI特征。
对作者所在机构数据库进行回顾性分析，以确定经组织学证实的PCNSL病例。检索图像并就病变位置、数量、大小、信号强度、强化特征、水肿及坏死情况进行分析。
31例经组织学证实的PCNSL病例有可用影像资料。1例因免疫抑制被排除。其余30例中，平均年龄65.5岁，男女比例均等。共识别出68个病灶（平均每位患者2.5个）。在扩散加权成像中，除2个病灶外其余均有扩散受限（40.3%为轻度，55.6%为重度），除1个病灶外其余均有强化（51.5%为均匀强化，42.6%为不均匀强化，环形强化占4.4%）。多数病灶在T2加权像（T2-WI）上与灰质等信号（占75.8%），在T1加权像（T1-WI）上占82.5%。43.4%的病灶水肿轻度，55.2%为重度。仅5个病灶（7.4%）出现坏死。以每位患者计，50%有双侧病灶，96.7%的病灶与脑脊液（CSF）表面接触。16.7%的患者有后颅窝受累，30%的患者病灶位于基底节或丘脑。
免疫功能正常患者的绝大多数PCNSL病例病灶与CSF表面接触、有强化及扩散受限且无坏死。这些特征应提醒放射科医生警惕PCNSL的诊断。
