磁共振成像在诊断颅内海绵状血管瘤中的应用价值

Application Value of Magnetic Resonance Image in the Diagnosis of Cerebral Cavernous Malformations

目的分析颅内海绵状血管瘤(cerebral cavernous malformations,CCMs)常规MRI序列表现及MRI磁敏感加权成像(susceptibility weighted imaging,SWI)的诊断价值。资料与方法回顾性分析50例经病理证实的CCMs患者的MRI资料,比较常规MRI序列(T1WI和T2WI)和SWI表现、检出率和病灶大小,判断其对CCMs的诊断价值。结果 50例共捡出97个病灶,22个病灶可见短T1信号伴出血,常规MRI对出血病灶具有多种表现形式;75个病灶未见短T1信号不伴出血。49个病灶T2WI灶周具有"铁环征";97个病灶中有48个病灶在T1WI或T2WI上呈"网格"状或"桑椹"状高、低混合信号;8个病灶T1WI、T2WI均呈高信号;6个病灶T1WI、T2WI均呈低信号;3个病灶T1WI呈等信号、T2WI呈稍低信号。SWI显示的病灶范围包括瘤体及灶周含铁血黄素区域,病灶信号不均匀性降低;SWI上90个病灶显示均匀或不均匀黑色信号,7个病灶显示混杂信号影。T1WI、T2WI、SWI对出血性病灶的检出率均为100%,SWI对非出血性病灶检出率为100%,显著高于T1WI和T2WI(18.6%和40.0%,P<0.05)。SWI显示出血性瘤体大小为(3.3±1.2)cm,显著大于T1WI和T2WI[(2.0±0.6)cm和(2.6±0.9)cm,P<0.05];SWI显示非出血性瘤体大小为(3.1±1.1)cm,显著大于T1WI和T2WI[(1.7±0.6)cm和(2.3±0.8)cm,P<0.05]。结论 MRI是诊断CCMs的首选方法,常规序列结合SWI序列能提供更准确和更全面的诊断信息。

Objective To analyze the imaging features of conventional MR and susceptibility weigeted image（SWI） in diagnosing Cerebral cavernous malformations（CCMs）.Materials and Methods MRI findings of 50 cases with CCMs,proved by pathology or clinic data were restrospectively analyzed.The detection rate and the features of lesion were compared between conventional MRI sequence（T1WI and T2WI） and SWI.Results Ninty seven lesions were detected in 50 cases.On T1WI,22 lesions showed short T1 signal associated with hemorrhage.On T2WI,49 lesions showed hoop like hypointense around the lesions.Among the 97 lesions,48 lesions showed strip or mulberry like mixed signal with hypointensity and hyperintenseity on T1WI and T2WI,8 lesions showed hyperintensity on T1WI and T2WI,6 lesions showed hypointensity on T1WI and T2WI,3 lesions showed iso-intensity signal on T1WI and slight hypointensity signal on T2WI.SWI can show the entity of tumor and surrounding hemosiderin deposition.90 lesions showed hypointensity signal and 7 lesions showed mixed signal on SWI.The detection rate of hemorrhage on T1WI,T2WI and SWI were all acted as 100%.75 lesions without hemorrhage were detected by SWI（100%）.SWI had higher detection rate than T1WI and T2WI in detecting CCMs without hemorrhage（18.6% and 40.0%,P0.05）.The mean diameter of CCMs with hemorrhage were（3.3±1.2） cm on SWI,which was larger than that on T1WI and T2WI[（2.0±0.6） and（2.6±0.9）,P0.05].The mean diameter of CCMs without hemorrhage were（3.1±1.1） cm on SWI,which was larger than that on T1WI and T2WI[（1.7±0.6） and（2.3±0.8）,P0.05].Conclusion MR imaging is the principle method to evaluate CCMs.Conventional MR combined with SWI can provide more accurate and complete information for accurate diagnosis.