Iosif Christina, Camilleri Yann, Saleme Suzana, Caire François, Yardin Catherine, Ponomarjova Sanita, Boncoeur-Martel Marie-Paule, Mounayer Charbel
Departments of 1 Interventional Neuroradiology.
J Neurosurg. 2015 Mar;122(3):627-36. doi: 10.3171/2014.10.JNS132566. Epub 2015 Jan 6.
It was initially considered safe for flow-diverting stents to cover the ostia of branching vessels during endovascular procedures for the treatment of intracranial aneurysms. As more recent evidence suggests, however, their use is not always free of ischemic concerns in terms of covered arterial ostia. The authors sought to determine the frequency of silent and clinically evident diffusion-weighted imaging (DWI)-detected abnormalities related to stent placement as a means of elucidating potential clinical risks.
This is a prospective single-center study on a series of patients with intracranial aneurysms that were treated with flow-diverting stents. All patients systematically underwent an MRI protocol that included DWI before treatment, between 24 and 48 hours postprocedure, and 3 months postembolization. Effectiveness of anticoagulation treatment was assessed for all patients. Lesions seen on DWI were correlated to the parent artery and the side-branch territories and were statistically analyzed in relation to their time of occurrence and clinical presentation. The authors compared the DWI findings in these patients to findings obtained in patients treated with a stent-assisted coiling technique during the same time period.
Over the course of 18 consecutive months, 38 consecutive patients (7 males and 31 females) with 49 intracranial aneurysms were treated using flow-diverting stents. Overall, 81.6% of the DWI spots found remained clinically silent during the follow-up period. Five ischemic clinical complications (13.2%) occurred in the postprocedural period. No statistically significant correlation could be established between DWI spots or aneurysm location and clinical complications or follow-up modified Rankin Scale score at 3 months. The complication rate was 7.8% (n = 3) at the 3-month follow-up, and mortality was 0%. Compared with stent-assisted coiling, use of flow-diverting stents showed a statistically significant correlation with silent DWI findings postintervention.
Lesions seen on DWI resulting from the procedure are far more common than anticipated, but the technique remains safe and effective, providing an interesting alternative for "difficult" aneurysms, regardless of location. Late-occurring DWI-detected lesions distal to side arterial branches imply a local pressure gradient drop, related to flow competition by collateral networks. Further research is needed to assess the extent and significance of these events.
在颅内动脉瘤血管内治疗过程中，最初认为血流导向支架覆盖分支血管开口是安全的。然而，最新证据表明，就被覆盖的动脉开口而言，其使用并非总是没有缺血方面的担忧。作者试图确定与支架置入相关的、通过扩散加权成像（DWI）检测到的无症状和有临床症状的异常情况的发生率，以此来阐明潜在的临床风险。
这是一项针对一系列接受血流导向支架治疗的颅内动脉瘤患者的前瞻性单中心研究。所有患者在治疗前、术后24至48小时以及栓塞后3个月均系统地接受了包括DWI在内的MRI检查。评估了所有患者的抗凝治疗效果。DWI上发现的病变与母动脉和侧支血管区域相关，并就其发生时间和临床表现进行了统计分析。作者将这些患者的DWI结果与同期接受支架辅助弹簧圈栓塞技术治疗的患者的结果进行了比较。
在连续18个月的时间里，38例连续患者（7例男性和31例女性）共49个颅内动脉瘤接受了血流导向支架治疗。总体而言，在随访期间，发现的DWI斑点中有81.6%在临床上无症状。术后发生了5例缺血性临床并发症（13.2%）。在DWI斑点或动脉瘤位置与临床并发症或3个月时的随访改良Rankin量表评分之间未发现统计学上的显著相关性。3个月随访时的并发症发生率为7.8%（n = 3），死亡率为0%。与支架辅助弹簧圈栓塞相比，血流导向支架的使用与干预后无症状的DWI结果存在统计学上的显著相关性。
该手术导致的DWI上可见的病变比预期更为常见，但该技术仍然安全有效，为“复杂”动脉瘤提供了一个有趣的替代方案，无论其位置如何。在侧支动脉分支远端后期出现的DWI检测到的病变意味着局部压力梯度下降，这与侧支网络的血流竞争有关。需要进一步研究来评估这些事件的程度和意义。
