高分辨率C形臂CT联合金属条纹伪影消除技术在颅内动脉瘤支架辅助栓塞中的应用

Clinical application of high-resolution C-arm CT scanning combined with streak metal artifact removal technology in stent-assisted embolization of intracranial aneurysms

目的探讨高分辨率C形臂CT扫描联合金属条纹伪影消除技术(SMART)在颅内动脉瘤介入治疗术中的应用价值,并评价其有效性。方法2018年1月至5月郑州大学第一附属医院郑东院区采用支架辅助弹簧圈栓塞连续治疗41例(42枚)颅内动脉瘤患者,术中和术后对支架置入区域分别作常规DynaCT和高分辨率DynamicroCT扫描,扫描图像经常规重建和SMART重建。2名神经介入专家对重建图像质量(支架金属丝显影程度、弹簧圈金属伪影程度等),并结合操作位造影对支架打开程度、动脉瘤栓塞致密程度等,进行观察和定量统计分析。结果42枚颅内支架(Neuroform EZ支架26枚,低剖面可视化腔内支架LVIS16枚)顺利辅助完成42枚动脉瘤栓塞(40例患者为单枚,1例为双枚)。与常规DynaCT重建和Dyna microCT重建相比,Dyna microCT联合SMART重建图像所示支架金属丝显影清晰,弹簧圈金属伪影消除明显,图像质量显著提高(P<0.05)。根据后者重建图像并结合操作位造影发现2枚支架局部打开不全,给予微导丝成襻支架内抚摸或球囊扩张后贴壁情况改善;4例患者瘤颈区栓塞未致密,调整微导管头端位置后继续栓塞术,直至栓塞效果满意。结论高分辨率Dyna microCT联合SMART能有效降低颅内动脉瘤栓塞术中支架和弹簧圈金属伪影,提高图像质量,有利于术者判定载瘤动脉内金属支架打开情况和动脉瘤瘤颈区栓塞是否致密,继而选择相应的治疗策略。这种新颖成像技术对于颅内动脉瘤介入治疗中评估具有较大应用价值。

Objective To assess the application value of high - resolution C - arm CT scanning combined with streak metal artifact removal technology(SMART) in stent- assisted embolization of intracranial aneurysms,and to evaluate its effectiveness.Methods From January 2018 to May 2018 at Zhengdong District Branch of the First Affiliated Hospital of Zhengzhou University of China,stent-assisted coil embolization was adopted in 41 consecutive patients with intracranial aneurysms(42 aneurysms in total).Both conventional C- arm CT(Dyna CT)scanning and high resolution C- arm CT(Dyna microCT)scanning of stent implantation areas were separately performed during and after the treatment.The obtained images were processed with conventional reconstruction and SMART reconstruction.Two experts of neurointervention evaluated the reconstruction image quality and conducted quantitative statistical analysis of reconstruction image quality, including the visualization degree of the meticulous structures of the stent,the coil metal artifact,the opening degree of stent,the density of the embolized aneurysm,etc.Results A total of 42 intracranial stents (26 Neuroform EZ stents and 16 LVIS stents)were used in successfully assisting embolization procedure of 42 aneurysms (single aneurysm in 40 patients and 2 aneurysms in one patient).Compared with Dyna CT with conventional reconstruction,Dyna microCT combined with SMART reconstruction remarkably improved the visualization of meticulous structures of the stent and strikingly reduced the metal artifacts produced by the platinum coils,the image quality was significantly improved (P<0.05).With the help of the images produced by Dyna microCT combined with SMART reconstruction,also combined with operating- position angiography imaging,incomplete opening of 2 stents was detected,after stent dilatation with looped micro- guidewire or balloon the stent position was improved.The density at aneurismal neck area was not thick in 4 patients,and the embolization procedure was continued after adjusting the head end position of the microcatheter until satisfactory embolization effect was obtained.Conclusion The combination use of high- resolution C- arm CT and SMART can effectively reduce the metal artifacts produced by the stent and coils and improve the quality of image,which are very helpful for the operator to judge the opening extent of metal stent in aneurysm parent artery and to estimate the embolization degree of the aneurysm neck area,based on which the operator can choose the corresponding treatment strategy.This novel imaging technique is of great value for making intraoperative evaluation in interventional operation of intracranial aneurysms.