原发性中枢神经系统淋巴瘤的影像学分析-定稿.doc

原发性中枢神经系统淋巴瘤的影像学分析 摘要：目的 探讨原发性中枢神经系统淋巴瘤（PCNSL）在影像学上具有的特征。方法 对收集的经过手术观察或者穿刺病理验证的17例PCNSL 患者的影像、病理资料进行回顾性分析。其中，8例和9例患者分别进行 CT和MRI检查，同时进行 CT、MRI和MRI及 PET/CT 检查的各1例。结果 17例PCNSL中，单发型13例、多发型2例、弥漫型2例；其中，幕上13例、幕下3例，弥漫分布1例。8例CT平扫呈等密度或者稍高密度，增强后呈轻中度强化。9例MRI检查T1WI呈等或低信号，T2WI呈等或稍高信号；注射Gd-DTPA 行增强后6例患者呈显著均匀强化，2例患者病灶中心见小囊变区；其中，5例和6例患者分别呈尖角征和脐凹征。除2例弥漫型PCNSL外，余15例PCNSL均呈轻中度占位效应及肿瘤周围水肿。2例弥漫型患者病灶呈T1WI低信号，T2WI高信号，增强后明显结节状强化，行PET/CT 扫描具有显著的18F-FDG高摄取。病理分析肿瘤表现为灰白色或者灰红色，质地柔软且无包膜，并具有较丰富的血运，镜下观察可见簇状分布肿瘤组织细胞大多数在血管四周。结论 在影像学上，PCNSL存在一定的特征表现，在临床工作中，可以用于提示诊断，必要时实施立体定位穿刺活检的方法予以确诊。 关键词：原发性中枢神经系统淋巴瘤；颅内肿瘤；影像学 Abstract: Objective To investigate the imaging features of primary central nervous system lymphoma (PCNSL). Methods The imaging and pathological findings in 17 patients with pathologically confirmed PCNSL were analyzed retrospectively. Of these patients, 8 underwent CT scan, 9 had magnetic resonance imaging (MRI) examination, 1 patient underwent both CT and MRI examinations and 1 patient had both MRI and PET/CT examinations. Results Among the 17 patients with PCNSL, 13 were identified to have solitary tumor foci, 2 had multiple lesions and 2 had diffuse lesions. Supratentorial tumors were found in 9 patients, infratentorial tumors in 3 patients, and suffuse tumors in 1 patient. In 6 cases, the tumor presented isodensity or slight hypodensity on plain CT images, with mild or moderate enhancement after contrast agent injection. The lesions showed isointense or hypointense signals on T1WI and isointense or slightly hypointense signals on T2WI in 9 cases, with obvious homogenous enhancement in 6 cases and microcystic foci in 2 cases after gadolinium injection. 5 patients showed the angular sign and 6 the hilar depression sign. All patients presented with mild or moderate peritumoral edema and space-occupying mass except for 2 patients with diffuse lesions, who showed hypointense signals on T1WI and hyperintense signals on T2WI with obvious nodular enhancement after gadolinium injection and high 18