零回波时间动脉自旋标记MR血管成像评估颅内动脉瘤介入治疗效果

Investigation of zero echo time arterial spin labeling MR angiography in the follow-up of endovascular treatment of intracranial aneurysm

目的 探讨零TE动脉自旋标记MR成像（zTE ASL MRA）技术在颅内动脉瘤介入治疗疗效评估中的应用价值.方法 颅内动脉瘤血管内介入治疗术后的患者,采用GE 1.5 T静音MR,同时进行zTE ASL MRA和时间飞跃法MR血管成像（TOF MRA）检查,并在MRA检查前后1周内进行DSA检查,评估动脉瘤栓塞效果和载瘤动脉支架内管腔的显示情况.以DSA作为金标准,评估两种MRA技术评估动脉瘤残存的敏感度、特异度、阳性预测值和阴性预测值.进行Kappa检验比较两种MRA技术与金标准DSA对动脉瘤栓塞后残存评估结果的一致性,以及阅片者之间、阅片者自身对动脉瘤治疗效果评估结果的一致性.应用配对t检验比较两种MR血管成像技术对载瘤动脉支架内管腔显示的差异.结果 24例患者（27个动脉瘤）中,23个动脉瘤进行支架辅助栓塞治疗,4个动脉瘤进行单纯栓塞治疗.DSA检出13个动脉瘤具有瘤腔残存,zTE ASL MRA检出15个,TOF MRA检出11个,zTE ASL MRA较TOF MRA具有更高的敏感度和阴性预测值,TOF MRA和zTE ASL MRA对动脉瘤栓塞治疗效果的评估与DSA均具有很好的一致性,Kappa值分别为0.70和0.85（P〈0.001）.对于zTE ASL MRA,不同阅片者之间的一致性良好,Kappa值为0.70,阅片者内的一致性也很高,Kappa值为0.85.对于23个放置支架的载瘤动脉,zTE ASL MRA可以对21个支架内的管腔进行准确评估,TOF MRA可较为准确评估12个,差异具有统计学意义（P〈0.05）.结论 与TOF MRA相比,zTE ASL MRA可以更好地评估颅内动脉瘤血管内介入治疗后的瘤腔残存,更好地显示载瘤动脉支架内的管腔.

Objective To investigate the value of zTE ASL MRA in the follow-up of interventional treatment of intracranial aneurysm at 1.5 T, using DSA as gold standard. Methods Patients with intracranial aneurysms who underwent coil embolization with or without stent were enrolled in this study. Both TOF MRA and zTE ASL MRA were performed on a 1.5T whole body scanner （MR360, GE, USA） equipped with an 8 channel head coil, and DSA was performed within one week of the MR examinations. Aneulysmal remnant and intra-stent opacity were analyzed. SE, PE, PPV, NPV of two MRA modalities in aneurysm reeanalization detection were calculated. Kappa coefficient was used to determine the inter-reader and intra-reader reproducibility. Paired t test was used to test the visibility of in-stent lumen on two kinds of MRA. Results A total of 24 patients （27 aneurysms） were included in this study, 23 aneurysms were treated with stent assisted embolization, four coil embolization. Thirteen cases of aneurysm remnant were detected by DSA, 15 by zTE ASL and 11 by TOF MRA. zTE ASL MRA had a relatively higher SE （100%） and NPV（100%） as compared with TOF MRA. The Kappa value in identification of aneurysm remnant was 0.85 between zTE MRA and DSA and 0.70 between TOF MRA and DSA, respectively. The inter-reader reproducibility was good （Kappa 0.70）, while the intra-reader reproducibility was excellent（Kappa 0.85）. There was statistical significance in the scoring results of the in-stent lumen visibility. Conclusion zTE ASL MRA proved to be a better imaging modality as compared to TOF MRA to evaluate the endovascular treatment effectiveness of intracranial aneurysms, especially for assessing the aneurysmal recurrence and in-stent lumen visibility.