磁敏感加权成像在脑膜瘤中的初步应用

Preliminary application of susceptibility weighted imaging in meningiomas

目的评估磁敏感加权成像（SWI）在脑膜瘤中的初步应用。方法回顾性纳入2015年10月至2018年2月南京医科大学附属脑科医院神经外科收治的50例脑膜瘤患者。所有患者术前均行头颅CT、MRI和SWI检查，将SWI图像经软件处理后获得最小强度投影图（mIP）；结合MRI或CT，对SWI的mIP、校正后的相位图进行对比分析，观察脑膜瘤的瘤内微出血灶、瘤内钙化灶和肿瘤引流静脉。对所有患者行手术切除治疗，术后进行病理学检查。进一步比较瘤内出血和瘤内未出血脑膜瘤患者的影像学和病理学指标。结果通过SWI检查，50例脑膜瘤患者中，7例（14％）有瘤内微出血灶（24个）；24例（48％）有瘤内钙化灶（47个），与CT检查结果比较，31个相符，16个不相符（均为CT未检出）；16例（32％）有明确的肿瘤引流静脉，其中11例无瘤周水肿，5例伴发瘤周水肿；18例（36％）无瘤周水肿，32例（64％）形成瘤周水肿。无瘤周水肿的患者较有瘤周水肿的患者更易形成引流静脉[分别为61％（11／18）、16％（5／32），P=0．001]。50例患者经病理证实均为WHOI级脑膜瘤。瘤内微出血组患者的水肿指数（EI）值、最大水肿宽度和Ki67值均高于瘤内未出血组（均P〈0．05），但两组患者孕激素受体阳性率的差异无统计学意义（P〉0．05）。结论SWI可检测出脑膜瘤的瘤内微出血灶、瘤内微钙化灶和肿瘤引流静脉。WHOI级脑膜瘤较少发生瘤内微出血，而发生瘤内微出血的脑膜瘤Ki67指数更高，瘤周水肿更严重，且脑膜瘤引流静脉可减轻瘤周水肿的形成。

Objective To evaluate the preliminary application of susceptibility weighted imaging （SWI） in meningiomas. Methods Fifty meningioma patients, treated at Department of Neurosurgery of Nanjing Brain Hospital Affiliated to Nanjing Medical University between October 2015 and February 2018, were retrospectively enrolled into this study. All eases underwent brain CT, MRI and SWI scans preoperatively, and the minimum intensity projection （mIP） was obtained through processing basic SWI images by software. Compared with MR/ and CT, intratumoral microhemorrhage, calcification and drainage vein in meningioma were analyzed in ndP and filtered phase imaging. Pathological examination was carried out after operation. Further comparative analysis was accomplished between microhemorrhagic group and non-microhemorrhagic group in imaging features and pathological indexes. Results Among the 50 meningioma patients examined by SWI, 7 （14%） had 24 intratumoral mierohemorrhages ; 24 （48%） had 47 intratumoral calcifications, including 31 calcifications that were consistent with CT and 16 which were not detected by CT; 16 （32%） clearly showed dominant draining veins originating from the tumor itself, consisting of 11 without peritumoral edema and 5 with peritumoral edema. The patients without peritumoral edema were more likely to form drainage veins than those with peritumoral edema [61% （11/18） vs. 16% （5/32）, P =0. 001 ]. All 50 patients were pathologically confirmed to have WHO Grade I meningiomas. The edema index （El）, maximum edenra width and Ki67 in the microhemorrhagic group were significant higher than those in non-microhemorrhagic group （all P 〈 0.05 ）, while there was no obvious difference between 2 groups in progesterone receptor （P 〉 0. 05 ）. Conclusions Intratumoral microhemorrhage, microcalcification and drainage vein can be detected by SWI. Intratumoral hemorrhages infreqnently occur in WHO Grade I meningiomas. Microhemorrhagic meningiomas have higher Ki67 and more serious peritumoral edema than non-hemorrhagic ones. The efferent draining vein from meningioma itself may alleviate the formation of peritumoral edema.