The fate of infrarenal abdominal aortic aneurysms after stent grafting: influence of thrombosis at side branch ostia

PURPOSE: To evaluate the effect of postoperative thrombosis of the side branch ostia on the shrinkage of endoluminally treated abdominal aortic aneurysms with patent side branch vessels. MATERIALS AND METHODS: Thirty-three patients were followed up with serial computed tomography (CT). Special attention was paid to presence or absence of retrograde enhancement of the side branch ostia after the covering of the patent side branch vessels by the stent graft and aneurysm diameter change on postoperative CT. Preoperative CT was also reviewed to assess the number of patent side branch vessels, degree of aneurysm wall calcification, and thickness of the mural thrombus. The patients with type 2 endoleak were excluded from this evaluation. The patients were divided into 2 groups, the nonthrombosed and thrombosed groups, based on presence or absence of retrograde enhancement of the side branch ostia as depicted on all postoperative CT. RESULTS: Type 1 endoleak was not seen in all patients. Preoperative diameter of the aneurysm was 4.75 +/- 0.18 cm in the thrombosed group (n = 12) and 4.98 +/- 0.35 cm in the nonthrombosed group (n = 8). There were no significant differences in follow-up periods, preoperative diameter of the aneurysm, number of patent side branch vessels, degrees of aneurysm wall calcification, and thickness of the mural thrombus between the 2 groups. The mean diameter of the aneurysm in the nonthrombosed group did not change at 3 and 6 months then first decreased at 12 months after the stent grafting. However, in the thrombosed group, the mean diameter of the aneurysm had decreased at 3 months after stent grafting. Thereafter, the aneurysms continuously shrank. CONCLUSIONS: Postoperative thrombosis of the side branch ostia may predict favorable shrinkage of endoluminally treated aneurysms.     

Type IIIb Endoleak Is Not Extremely Rare and May Be Underdiagnosed after Endovascular Aneurysm Repair

PurposeTo investigate the real incidence of type IIIb endoleaks associated with the Zenith stent graft, currently the most widely used third-generation polyester stent graft, in a Japanese multicenter database.Materials and MethodsRetrospective analysis was conducted of 433 patients who underwent endovascular aneurysm repair (EVAR) of aortoiliac aneurysms with the use of Zenith stent grafts from 2007 to 2016. The mean age of patients was 75.6 y ± 7.8, and 85.2% of patients were men. Mean transverse diameters of abdominal aortic aneurysms and common iliac artery aneurysms were 50.8 mm ± 9.9 and 42.2 mm ± 10.3, respectively.ResultsDuring a mean follow-up period of 41.9 mo, 7 type IIIb endoleaks (1.6%) were identified. Four patients were definitively diagnosed during repeat intervention, and 3 were diagnosed based on postoperative CT images. Three patients were treated surgically, 2 were treated by relining with an additional stent graft, and 2 were conservatively followed with CT imaging. Only 1 of 5 patients who underwent repeat intervention had a preoperative diagnosis of type IIIb endoleak, reflecting the difficulty in its diagnosis.ConclusionsThe incidence of type IIIb endoleak in Zenith stent grafts was 1.6% in this study, suggesting that type IIIb endoleaks are not extremely rare. In addition, type IIIb endoleak may be underdiagnosed or misdiagnosed as a different type of endoleak. Type IIIb endoleaks should always be considered in patients with sac expansion after EVAR.     

Polytetrafluoroethylene-encapsulated stent-grafts: use in experimental abdominal aortic aneurysm.

PURPOSE: To evaluate expanded polytetrafluoroethylene (ePTFE) encapsulated stents for the treatment of aortic aneurysms with emphasis on the blood and tissue-material interactions. MATERIALS AND METHODS: Experimental aortic aneurysms were created in dogs by enlarging the aortic lumen with an abdominal fascial patch. Twenty animals underwent endoluminal repair after allowing the surgically created aneurysm to heal for 2 months prior to transluminal aneurysmal exclusion. The device used consisted of an 8-cm-long ePTFE encapsulated stent graft. The animals were killed in groups at 1 week and at 1, 2.25, 6, and 12 months. Specimens were processed for histologic and luminal surface studies. RESULTS: Before the animals were killed, aortography demonstrated two thrombosed aortae in the 6-month group and two endoleaks in the 12-month group. Endothelialized neointima extended into the proximal and distal portions of the prosthetic lumen, with minimal cell coverage in the center of the graft. The overall percent surface area covered by endothelialized neointima was 22% +/- 6% at 6 months and 18% +/- 10% by 1 year (P = .75). Histologic examination demonstrated minimal tissue penetration into the ePTFE. CONCLUSION: Transluminal exclusion of abdominal aortic aneurysms by encapsulated stent-graft is easily accomplished. With this device, tissue coverage and penetration of the stent graft is limited and does not tend to increase with time.     

Parallel Covered Stents Technique in the Treatment of Abdominal Aortic Diseases

PurposeTo investigate the safety and efficacy of the parallel covered stents technique in the treatment of anatomically challenging aortic aneurysms, pseudoaneurysms, and dissections.Materials and MethodsData were retrospectively collected from 16 patients with abdominal aortic diseases who were treated with parallel covered stents (Gore Excluder, n = 14; Medtronic Endurant, n = 2) between January 2016 and July 2018. Patients were treated with this technique if they were unsuitable for either open repair or standard endovascular aortic repair with bifurcated stents. Such unfavorable anatomy included narrow aortic necks (≤18 mm), small vascular access (occluded or ≤6.0 mm), or compressed aortic lumens (≤18 mm). All patients were male, with a mean age of 64.7 ± 13.3 years. For true aneurysms (n = 4) and pseudoaneurysms (n = 4), the mean diameter and length of the proximal necks were 17.5 ± 2.6 mm (range, 14–21 mm) and 51.0 ± 12.5 mm (range, 39–75 mm), respectively. The minimal diameter of true lumen in cases with aortic dissection and penetrating ulcers (n = 8) was 14.8 ± 3.1 mm. Small or occluded femoral access was found in 3 patients.ResultsTechnical success was 100%. Minor type I endoleaks, which were seen on completion angiography in 5 patients, had all resolved within 3 months. There were no perioperative deaths. Postoperative complications included supraventricular tachycardia in 1 patient and pneumonia combined with heart failure in 1 patient. Patency of all stents was observed at a mean follow-up of 21.8 ± 10.1 months.ConclusionsThe parallel covered stents technique appears to offer a feasible solution for abdominal aortic diseases with unfavorable anatomy. Long-term follow-up is needed to further evaluate the safety and efficacy of this technique.     

Juxtarenal aortic aneurysm: endoluminal transfemoral repair?

Endoluminal transfermoral repair of an abdominal aortic aneurysm by a stent graft placement requires a segment of the nondilated infrarenal aorta of at least 15 mm long for safe stent graft attachment. The possibility of endoluminal treatment of a juxtarenal abdominal aortic aneurysm with partially covered spiral Z stent was assessed in experiment and in three clinical cases. In the experiment, the noncovered spiral Z stent was placed into the abdominal aorta, across the origins of renal arteries and mesenteric arteries, in six dogs. In the clinical cases, a partially covered stent graft was attached in 3 patients with the juxtarenal abdominal aortic aneurysm (of the group of 12 patients with abdominal aortic aneurysm). The stent grafts were attached with proximal uncovered parts across the origins of the renal arteries. In experiment, the renal artery occlusions or stenoses were not observed 36 months after stent placement, and in clinic 3 patients with the juxtarenal aortic aneurysm were successfully treated by stent graft placement. There were no signs of flow impairment into the renal arteries 14 months after stent graft implantation. This approach can possibly expand the indications for endoluminal grafting in the treatment of juxtarenal aortic aneurysms in patients who are at high risk for surgery.     

Endovascular Treatment of Multiple HIV-related Aneurysms Using Multilayer Stents

Complex peripheral aneurysm anatomy with major artery branches in the immediate vicinity and mycotic aneurysm often impede endovascular management using covered stent grafts. The Cardiatis Multilayer Stent (Cardiatis, Isnes, Belgium) is a recently approved innovative stent system for peripheral aneurysm management. Its multilayer design aims at decreasing mean velocity and vorticity within the aneurysm sac to cause thrombus formation while maintaining patency of branching vessels due to laminar flow. We present a case of bilateral subclavian artery aneurysms and perivisceral aortic aneurysms in an AIDS patient successfully treated with the Cardiatis Multilayer Stent at 18 months' follow-up.     

Endovascular Treatment of Concurrent Bilateral Common and Internal Iliac Artery Aneurysms with Preserved Pelvic Circulation: Bilateral Iliac Branch Devices with Opposing Single Division Internal Iliac Artery Sparing

An 83-year-old man with bilateral common iliac artery aneurysms (right, 3.0 cm; left, 2.7 cm), bilateral internal iliac artery aneurysms (right, 3.4 cm; left, 2.6 cm), and an abdominal aortic aneurysm (3.8 cm) was treated with an aortobi-iliac stent graft and bilateral iliac branch devices. The internal iliac components were extended into opposing posterior (left) and anterior (right) divisions of the internal iliac artery using stent grafts. Computed tomography angiography demonstrated that all aneurysms decreased or were stable in size with patent stent grafts at 1 month. The patient was asymptomatic without complications of pelvic ischemia at the last clinical follow-up at 6 months.     

Endovascular treatment of intracranial vertebral artery dissections with stent placement or stent-assisted coiling

BACKGROUND AND PURPOSE: Endovascular treatment with stent placement or stent-assisted coiling was recently introduced as an alternative to parent artery occlusion in intracranial vertebral artery dissections. We describe the efficacy and limitations of this method. METHODS: Fourteen patients with intracranial vertebral artery dissection were treated with stent placement (10 patients) or stent-assisted coiling (4 patients). Double overlapping stents were deployed in 4 of 10 patients with stent placement alone. Angiographic follow-up at 6 to 12 months was available in 13 patients. RESULTS: In 13 patients with dissecting aneurysm, immediate angiographic outcomes were complete occlusion (1 patient), nearly complete (2 patients), and incomplete (10 patients). Follow-up angiograms of 12 of these patients showed complete occlusion (6 patients) and incomplete (6 patients; 1 unstable and 5 stable). Complete occlusion rates in follow-up angiograms were superior in double stent placement (75%) or stent-assisted Guglielmi detachable coil (GDC) embolization to stent placement alone (0%). There were no instances of postprocedural ischemic attacks, new neurologic deficits, and no new minor or major strokes before patient discharge. On the modified Rankin scale applied in follow-up, all patients were assessed as functionally improved or of stable clinical status. CONCLUSIONS: Intracranial vertebral artery dissections were acceptably treated with stent placement or stent-assisted coiling, and the patency could be preserved at follow-up. However, the efficiency of stent placement alone for intracranial vertebral artery dissecting aneurysm was limited. Stent-assisted coil embolization or double stent placements are a viable alternative for complete occlusion of dissecting aneurysms.     

Elective endovascular treatment of descending thoracic aortic aneurysms and chronic dissections with stent-grafts

PURPOSE: To report our experience of endovascular stent-graft placement in patients with descending thoracic aortic dissections and aneurysms and to evaluate the feasibility, safety, and clinical outcomes of the treatment. MATERIALS AND METHODS: Stent-grafts were placed in the descending thoracic aortas of 23 patients with saccular aneurysms (n = 11) and Stanford type B chronic aortic dissections of the descending thoracic and abdominal aorta (n = 12). All stent-grafts were individually constructed of self-expandable stainless steel stents covered with polytetrafluoroethylene. Vascular access was achieved through the femoral artery in all patients. Clinical status of each patient was monitored and postoperative CT was performed within 1 month of the procedure and at 3-12-month intervals after the procedures. RESULTS: Successful exclusion of the primary entry tears of dissections and the inlets of saccular aneurysms was achieved in all but two patients with aortic dissection. The overall technical success rate was 91.3% (dissection: 10 of 12 = 83%; aneurysm: 11 of 11 = 100%). All patients in whom technical success was achieved showed complete thrombosis and significant decrease in diameter of the thoracic false lumen (preoperative: 5.3 cm +/- 0.9; postoperative: 4.3 cm +/- 0.9; P = .004) or aneurysm sac (preoperative: 5.3 cm +/- 1.7; postoperative: 2.8 cm +/- 2.5; P = .001). In addition, five patients demonstrated complete resolution of the dissected thoracic false lumen (n = 2) and aneurysm sac (n = 3). However, in all patients with aortic dissection, the abdominal aorta was not significantly changed in size (P = .302) and shape and their false lumen flows remained persistent. Immediate postoperative complications were detected in 12 patients (52%); 10 had fever, leukocytosis, and elevation of C-reactive protein, another had wound infection, and another had transient abdominal pain. Three patients died 2, 3, and 12 months after the procedure: one from septic shock, another from underlying mediastinitis, and the other from an unexplained cause. The remaining 20 patients were well after the procedure (1-9 days; mean, 3 days), without any stent-graft-related complications or discomfort (follow up period: 10-65 mo; mean: 25.1 mo +/- 15.6). The cumulative survival rate after the stent graft was 100% at 30 days and 91% at 12 months. CONCLUSIONS: For treatment of aortic dissection and saccular aneurysm of the descending thoracic aorta, endovascular stent-graft repair may be a technically feasible and effective treatment modality.     

Volume changes of extremely large and giant intracranial aneurysms after treatment with flow diverter stents

Introduction

This study assessed volume changes of unruptured large and giant aneurysms (greatest diameter >20 mm) after treatment with flow diverter (FD) stents.

Methods

Clinical audit of the cases treated in a single institution, over a 5-year period. Demographic and clinical data were retrospectively collected from the hospital records. Aneurysm volumes were measured by manual outlining at sequential slices using computerised tomography (CT) or magnetic resonance (MR) angiography data.

Results

The audit included eight patients (seven females) with eight aneurysms. Four aneurysms involved the cavernous segment of the internal carotid artery (ICA), three the supraclinoid ICA and one the basilar artery. Seven patients presented with signs and symptoms of mass effect and one with seizures. All but one aneurysm was treated with a single FD stent; six aneurysms were also coiled (either before or simultaneously with FD placement). Minimum follow-up time was 6 months (mean 20 months). At follow-up, three aneurysms decreased in size, three were unchanged and two increased. Both aneurysms that increased in size showed persistent endosaccular flow at follow-up MR; in one case, failure was attributed to suboptimal position of the stent; in the other case, it was attributed to persistence of a side branch originating from the aneurysm (similar to the endoleak phenomenon of aortic aneurysms). At follow-up, five aneurysms were completely occluded; none of these increased in volume.

Conclusion

Complete occlusion of the aneurysms leads, in most cases, to its shrinkage. In cases of late aneurysm growth or regrowth, consideration should be given to possible endoleak as the cause.     

Urgent thoracic aortal dissection and aneurysm: treatment with stent-graft implantation in an angiographic suite

The aim of this study was to evaluate the feasibility of endoluminal stent-graft placement in an angiographic suite for the treatment of emergent type-B aortic dissections and ruptured thoracic aortal aneurysms. Twenty-six patients with either urgent type-B dissection (n=8) or aneurysms (n=18) of the descending thoracic aorta were chosen for stent-graft implantation. All patients received a multidetector-row CT angiography of the whole aorta and pelvic arteries prior to stent-graft implantation. All procedures were performed in a fully equipped digital subtraction angiography (DSA) suite under general anesthesia. In 20 patients Talent LPS tube grafts and in 4 patients an Excluder graft were used. Access was achieved via surgical cut-down in the left (n=7) or right (n=19) groin. Sealing was successful in 24 patients. The proximal covered portion of the stent graft was placed across the left subclavian artery in 2 patients. Procedural success was achieved in 23 of 24 patients. One patient required a second stent-graft placement before the aneurysm was sealed. One patient with an acute perforation of the descending aorta died due to cardiac failure prior to stent-graft implantation. In 1 patient stent-graft delivery failed due to severe calcification of both common iliac arteries. Endoluminal treatment of both urgent type-B aortic dissections and thoracic aortal aneurysms with stent graft is an attractive alternative treatment to surgical repair. The placement of stent grafts in an angiographic suite is a safe and feasible method with good clinical effectiveness and, so far, good clinical outcome.     

Endovascular placement of a nitinol-ePTFE stent-graft for abdominal aortic aneurysms: initial and midterm results

PURPOSE: Because first-generation stent-grafts did not meet initial expectations, a recently designed nitinol-expanded polytetrafluoroethylene (ePTFE) stent-graft was tested for treatment of abdominal aortic aneurysms (AAAs) in a prospective clinical study. The primary study endpoints were technical success and safety. MATERIALS AND METHODS: A nitinol-ePTFE self-expandable stent-graft (Excluder) was used to treat 72 patients with AAAs. The median follow-up period was 21.5 months +/- 13 (range, 1-46 mo). RESULTS: Primary technical success in accurate placement of the device was achieved in 70 of 72 patients (97%). Complete exclusion of the aneurysm from arterial flow was achieved in 57 of 72 patients (79.2%). Three type I leaks were observed during implantation and were immediately corrected with a proximal cuff prosthesis in two patients. Fourteen of 72 patients (19.4%) had a type II leak. Major complications were observed in three patients (4.1%), including one death in the early postinterventional period (one of 72, 1.4%). At 3 months, aneurysms were excluded in 70 of 71 patients (98.6%), and at 12 months, aneurysms were occluded in 29 of 30 patients (96.7%). The maximum diameter of the aneurysm decreased from 55 mm +/- 11 (median +/- SD) before intervention to 53 mm +/- 13 at 6 and 12 months. None of the patients showed aneurysm growth. CONCLUSION: This newly designed stent-graft proved to be effective and safe for treatment of AAAs.     

Late angiographic and clinical follow-up results of 100 consecutive aneurysms treated with Onyx reconstruction: largest single-center experience

We present the long-term clinical and angiographic follow-up results of 100 consecutive intracranial aneurysms treated with Onyx liquid embolic system (MTI, Irvine, Calif.), either alone or combined with an adjunctive stent, in a single center. A total of 100 aneurysms in 94 patients were treated with endosaccular Onyx packing. Intracranial stenting was used adjunctively in 25 aneurysms including 19 during initial treatment and 6 during retreatment. All aneurysms except two were located in the internal carotid artery. Of the 100 aneurysms, 35 were giant or large/wide-necked, and 65 were small. Follow-up angiography was performed in all 91 surviving patients (96 aneurysms) at 3 and/or 6 months. Follow-up angiography was performed at 1, 2, 3, 4 and 5 years in 90, 41, 26, 6 and 2 patients, respectively. Overall, aneurysm recanalization was observed in 12 of 96 aneurysms with follow-up angiography (12.5%). All 12 were large or giant aneurysms, resulting in a 36% recanalization rate in the large and giant aneurysm group. One aneurysm out of 25 treated with the combination of a stent and Onyx showed recanalization. There was also no recanalization in the follow-up of small internal carotid artery aneurysms treated with balloon assistance only. At final follow-up, procedure- or device-related permanent neurological morbidity was present in eight patients (8.3%). There were two procedure-related and one disease-related (subarachnoid hemorrhage) deaths (mortality 3.2%). Delayed spontaneous asymptomatic occlusion of the parent vessel occurred in two patients, detected on routine follow-up. Onyx provides durable aneurysm occlusion with parent artery reconstruction resulting in perfectly stable 1-year to 5-year follow-up angiography both in small aneurysms treated with balloon assistance only (0% recanalization rate) and large or giant aneurysms treated with stent and Onyx combination (4% recanalization rate). Endosaccular Onyx packing with balloon assistance may not be adequate for stable long-term results in those with a large or giant aneurysm. However, the recanalization rate of 36% in these aneurysms is better than the reported results with other techniques, i.e., coils with or without adjunctive bare stents.     

Infrarenales Bauchaortenaneurysma

As an alternative to surgery, endovascular therapy with stent grafts has become the second main treatment option for infrarenal abdominal aortic aneurysms. Unlike surgery, endovascular treatment with stent grafts is also applicable in patients unfit for open repair. Despite current improvements in endovascular repair devices, significant anatomic barriers still exclude this technique for a large number of patients. Computed tomography, magnetic resonance imaging, and ultrasound are essential for diagnostics, preintervention planning, and postintervention follow-up of abdominal aneurysms treated with stent grafts. This review covers etiology, pathology, and diagnostic aspects. Materials and methods for endovascular treatment of abdominal aortic aneurysms are presented in detail, and clinical results and complications are discussed.     

巨大动脉瘤的介入治疗

目的探讨巨大动脉瘤介入治疗的方法及疗效。方法对7例巨大动脉瘤(包括肺动脉瘤2例,肾动脉瘤2例,肱动脉瘤1例,右髂总动脉瘤1例,右髂内动脉瘤1例;其中真性动脉瘤5例,假性动脉瘤2例;原因为先天性、外伤性以及动脉硬化所致)3例采用置入带膜血管内支架治疗,2例采用动脉瘤内填塞治疗,2例采用部分动脉瘤内填塞加供血动脉栓塞治疗。结果7例巨大动脉瘤顺利完成了介入治疗手术,技术成功率为100％。6例动脉瘤闭塞,症状体征消失;1例右髂内动脉瘤复发破裂死亡。未出现其他并发症。结论介入方法是治疗巨大动脉瘤的有效方法。     

CT断层图像和三维重建在主动脉腔内隔绝术术前评估中的价值

目的比较CT断层图像和三维重建在主动脉腔内隔绝术术前评估中的价值。方法将接受主动脉腔内隔绝术的20例主动脉夹层瘤和12例腹主动脉瘤患者作为研究对象,术前分别在CT断层图像与三维重建图像上测量的各相关参数,与主动脉造影所测量的相同参数进行对照分析。结果CT断层图像上所测量的主动脉弓直径及各种长度指标均小于主动脉造影结果;夹层瘤近段主动脉直径及近端瘤颈直径、主动脉中段直径以及左右髂动脉直径均大于主动脉造影结果;三维重建所测量的上述各项参数与主动脉造影结果非常接近,并能清楚显示夹层分离的破裂口,而断层图像上不易发现破裂口;断层图像和三维重建在显示主动脉附壁血栓和测量最大瘤体直径方面优于主动脉造影。以三维重建测量为标准选择覆膜支架,所有患者均成功封闭瘤体。结论主动脉腔内隔绝术术前评估时应结合CT断层图像和三维重建图像综合分析,覆膜支架的选择应以三维重建测量结果为主。     

Custom bifurcated stent-graft for abdominal aortic aneurysms: initial experience.

PURPOSE: To describe a custom bifurcated stent-graft for possible treatment of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: Five male patients (mean age, 76 +/- 6 years), who had AAA (mean diameter, 4.7 +/- 0.4 cm) and who were considered to be at high risk for conventional surgery, were treated with a custom modular bifurcated stent-graft constructed with bifurcated 24-mm x 12-mm (upper body diameter x iliac limb diameter) Cooley Veri-Soft Woven polyester grafts and Gianturco-R?sch Z stents. The stent-graft body was delivered through 20-22-F sheaths, and the contralateral iliac limb was delivered through a 16-F sheath by means of surgical exposure of the common femoral arteries. A flared distal limb extender (12 mm to 14 mm) was created for one patient to accommodate a large common iliac artery. RESULTS: Stent-grafts were successfully deployed without complications in all five patients. There were no proximal or distal leaks. A lumbar-to-inferior mesenteric artery leak was seen in one patient at 24 hours. At 6-month follow-up, all devices were intact, with complete exclusion and shrinkage of the aneurysm in four of five patients. Aneurysm size remained stable in the one patient with a lumbar-to-inferior mesenteric artery leak. CONCLUSION: A custom, bifurcated stent-graft was utilized for endovascular treatment of AAA. Long-term follow-up is necessary for the device.     

Behandlung von Aneurysmen der Aorta abdominalis und der Becken-/Beingefäße mittels Stentgrafts

The implantation of stent grafts is a relatively new method for the treatment of aneurysms of the aorta or peripheral aneurysms. Before the implantation precise measurements are mandatory to obtain the necessary information about the aneurysm. The numerous contraindications must be observed strictly to successfully exclude the aneurysmal sac. The stent graft is inserted via a percutaneous puncture or, in the case of an aortic graft, through a surgical arteriotomy. After the implantation rigorous follow-up is mandatory to detect complications such as leaks or thrombi: Spiral CT angiography is the method of choice. Some of the complications require secondary interventions such as the implantation of additional stent grafts. The results are encouraging, with a secondary exclusion rate of the aneurysm of up to more than 95%; however, long-term results are not available.     

Neuroform颅内支架辅助栓塞宽颈颅内动脉瘤的初步经验

目的　报道我科使用Neuroform支架辅助可脱式弹簧圈栓塞宽颈脑动脉瘤的初步经验。方法　 2 2例 2 4枚宽颈颅内动脉瘤采用Neuroform支架和弹簧圈进行栓塞 ,其中急性破裂动脉瘤 19枚、未破裂动脉瘤 5枚。结果　支架均成功地释放 ,支架置入后的造影未发现有瘤内造影剂滞留的血流动力学改变。 10 0 %闭塞动脉瘤 18枚 ,90 %以上闭塞 5枚 ,1枚伴发的未破裂小型宽颈动脉瘤在支架置入后微导管无法超选 ,载瘤动脉均通畅。有 2枚动脉瘤虽有支架阻挡 ,但仍有部分弹簧圈畔进入载瘤动脉。所有患者没有出现与支架置入有关的症状性缺血性并发症。 17例造影随访中 ,有 1例在 3个月复查时发现再通 ,进行 2次栓塞完全闭塞动脉瘤 ,其余未见复发 ,结论　Neuroform颅内支架使用安全有效 ,适合于宽颈颅内动脉瘤的支架辅助弹簧圈栓塞 ,特别适合于迂曲的脑血管 ;其径向支撑力较差 ,在输送微导管时应防止其移位 ;其支架网眼较大 ,对血流动力学改变不明显 ,致密填塞是重要的 ,在输送弹簧圈时仍应防止弹簧圈畔进入载瘤动脉 ;术前、术后抗血小板药物的应用以及术后严格的系列造影随访是必要的。     

Endovascular stent graft repair of abdominal aortic aneurysms: Current status and future directions

Endovascular stent graft repair of abdominal aortic aneurysm (AAA) has undergone rapid developments since it was introduced in the early 1990s. Two main types of aortic stent grafts have been developed and are currently being used in clinical practice to deal with patients with complicated or unsuitable aneurysm necks, namely, suprarenal and fenestrated stent grafts. Helical computed tomography angiography has been widely recognized as the method of choice for both pre-operative planning and post-operative follow-up of endovascular repair (EVAR). In addition to 2D axial images, a number of 2D and 3D reconstructions are generated to provide additional information about imaging of the stent grafts in relation to the aortic aneurysm diameter and extent, encroachment of stent wires to the renal artery ostium and position of the fenestrated vessel stents. The purpose of this article is to provide an overview of applications of EVAR of AAA and diagnostic applications of 2D and 3D image visualizations in the assessment of treatment outcomes of EVAR. Interference of stent wires with renal blood flow from the hemodynamic point of view will also be discussed, and future directions explored.