关键词: 磁共振波谱成像, 磁共振表现, 误诊分析, 磁敏感加权成像, 脑外型海绵状血管瘤

Abstract: ［Abstract］ Objective To summarize the MRI features and reasons of misdiagnosis of intracranial extracerebral cavernous malformations （ECMs） for improving the diagnostic level. Methods The MRI manifestations of 9 patients diagnosed ECMs with surgically and pathologically were retrospectively analyzed. The lesion and signal characteristics were observed， and misdiagnosis was analyzed by combining pathological characteristics. Results MRI examination of 9 patients had multiple lesions in 2 cases， namely， internal auditory canal combined with intracerebral cavernous hemangioma， single lesion in 7 cases， with the location at cavernous sinus in 3 cases， at middle cranial fossa， posterior horn of lateral ventricle， the fourth ventricle and confluence of sinuses separately each had one. Peripheral tissue edema in 1 case and no edema in 8 cases. Non?uniform signal were found in 5 patients， uniform signal was found in 4 patients， presenting as iso?signal on T1WI， high?signal on T2WI and FLAIR， and heterogeneous enhancement， the intensity of which was similar to vascular enhancement. Presenting iso?signal on susceptibility weighted imaging（SWI） in 3 cases， and heterogeneous signal in 4 cases. Presenting mild high?signal on diffusion weighted image（DWI） in 3 case and heterogeneous iso?signal in 1 case， presenting slightly high?signal on appearance diffusion coefficient（ADC） in 4 cases. The choline（Cho） peak and N?Acetyl?L?aspartic（NAA） peak recorded at baseline level in 3 patients were scanned magnetic resonance spectrum（MRS）， one of which was found Lactate（Lac） peak. One patient presented low blood flow of brain in perfusion weighted imaging（PWI）. Conclusion ECMs are cerebral vascular malformations，which are characterized by high?signal on T2WI and FLAIR，finding “iron ring sign”， with low perfusion and rare peripheral tissue edema. Making use of new technology such as SWI， MRS， PWI， can increase the diagnostic accuracy of ECMs， as well as providing comprehensive and accurate information for clinical therapy.

Key words: susceptibility weighted imaging；magnetic resonance spectroscopy, misdiagnosis analysis, extracerebral cavernous malformations MRI features