24例原发性中枢神经系统血管炎患者的MRI表现

目的观察24例原发性中枢神经系统血管炎(PACNS)的磁共振成像(MRI)表现,探讨PACNS的MRI诊断价值。方法对急性期进行了MRI检查的24例经病理证实的PACNS的MRI特点进行了回顾性分析。结果 24例患者中,病灶以幕上多见[19例(79.2%)],最常累及颞叶、额叶、顶叶及基底节区(包括丘脑),分别为13例(54.2%)、10例(41.7%)、8例(33.3%)、8例(33.3%);大部分病灶累及双侧大脑半球[15例(72.5%)],灰质和白质均受累[21例(87.5%)]。MRI上病灶可多发或单发,均为12例(50%)。病灶形态大致可分为四种类型:斑片状、肿块样、脑回状和混合性,分别为12例(50%)、8例(33.3%)、2例(8.3%)和2例(8.3%)。MRI上所有病灶均呈长(稍长)T1WI、长(稍长)T2WI异常信号,增强扫描可见病灶均有强化,FLAIR上均呈高或稍高信号,9例(37.5%)病灶中心呈散点状短T1WI、短T2WI混杂信号。17例行DWI和ADC序列检查者中,9例(52.9%)在DWI上呈高(稍高)信号,ADC上呈等信号或混杂信号影,8例(47.1%)在DWI及ADC上呈等信号。11例行GRE序列检查者,8例(72.7%)可见病灶局部有点状低信号影或病灶周围血管影增粗,余3例未见异常。8例行MRA序列检查者,仅1例发现异常,可见病灶供血区相应血管局部有狭窄。结论本组24例PACNS患者急性期头MRI均有异常,表现多样,病灶以幕上多见,可累及各个脑区,病灶可多发或单发,多数灰白质均受累。其形态可表现为斑片状、肿块样、脑回状或混合性,增强扫描均可见强化,以斑片状或脑回样强化多见。头MRI上病灶多变、灰白质受累、斑片状或脑回样强化等表现对PACNS诊断有一定提示性。

MR imaging features of the primary angiitis of the central nervous system

Objective To describe the magnetic resonance imaging (MRI) features of 24 cases with primary angiitis of the central nervous system (PACNS ) and to discuss MRI diagnostic value for PACNS. Methods 24 cases with biopsy-proven PACNS , who were in the acute stage and underwent MRl were reviewed. The findings of MRI were retrospectively analyzed. Results Brain MRI of the 24 cases showed that the lesions were mainly located in supratentorium [19 cases (79.2% ) ] . 13 cases (54.2% ) in the frontal lobe ,10 cases (41.7% ) in the temporal lobe ,8 cases (33.3% ) in the parietal lobe and the basal ganglia (including thalamus) . Most of lesions were bilateral [15 cases (72.5% )] and affected cortex and subcortical regions [21 cases (87.5% )] . 12 cases (50% ) had single lesions ,others had multiple lesions. As for the shape of the lesion ,12 cases (50% ) were patchy ,8 cases (33.3% ) were mass-like ,2 cases (8.3% ) were cerebriform and 2 cases (8.3% ) were hybrid. MRI signal features :all lesions of 24 cases showed long T1 signal ,long T2 signal , increased fluid-attenuated inversionrecovery signal and with postgadolinium enhancement. On diffusion weighted imaging and apparent diffusion coefficient ,9/17 cases (52.9% ) showed abnormal signal , 8/11 cases (72.7% ) on gradient echo imaging showed low signal or thickening of blood vessels around the lesion ,and only 1/8 cases (12.5% ) in magnetic resonance angiography had vascular stenosis close to the lesions.Conclusions The MRI features of PACNS at the acute stage varied. The lesions were mainly located in supratentorium involving the all the brain areas ,either single or multipl , most commonly affecting cortex and subcortical regions. Lesions could be patchy ,mass-like ,cerebriform or hybrid ,with postgadolinium enhancement. The patchy and cerebriform were common. Different sequence of MRI had its own features.