Enterprise支架治疗复杂症状性颅内动脉粥样硬化性狭窄

目的评估Enterprise支架治疗复杂症状性颅内动脉粥样硬化性狭窄(intracranial atherosclerotic stenosis,ICAS)的安全性和有效性。方法收集2014年1月-2016年6月首都医科大学附属北京天坛医院介入神经病学科收治的24例复杂症状性ICAS[如路径迂曲,病变长(15 mm),病变接近分叉,狭窄合并动脉瘤等]并经亚满意球囊扩张+Enterprise支架治疗的患者资料。主要终点事件定义为支架术后30 d内任何卒中(包括缺血性和出血性)、短暂性脑缺血发作(transient ischemic attack,TIA)或者死亡。次要终点事件为支架治疗成功;随访期间50%的支架内再狭窄或者靶血管供血区的卒中或TIA。结果 24例入组患者中,主要终点事件发生率为4.2%(1/24),表现为无症状性蛛网膜下腔出血(subarachnoid hemorrhage,SAH),无缺血性并发症发生。支架治疗技术成功率为100%,血管狭窄率从(87.1±9.3)%降为(17.5±8.7)%。4枚狭窄附近动脉瘤同时栓塞。共18例患者进行了影像学随访,6例患者(33.3%)发生了支架内再狭窄。其中3例患者为症状性再狭窄并进行了支架内球囊扩张。结论亚满意球囊扩张+Enterprise支架置入治疗颅内复杂动脉粥样硬化性狭窄技术可行,具有较低并发症。经导管释放的支架可能提高支架治疗的安全性。     

颅内动脉瘤血管内栓塞治疗的临床分析

目的总结颅内动脉瘤血管内栓塞治疗技巧及结果。方法采用血管内栓塞治疗76例80个颅内动脉瘤。对23个宽颈动脉瘤采用瘤颈成形辅助技术栓塞治疗,其中球囊辅助成形术治疗动脉瘤4个,微导丝辅助瘤颈成形技术治疗5个,支架结合弹簧圈栓塞治疗14个。6个巨大动脉瘤5个用可脱性球囊闭塞载瘤动脉,1个用电解可脱性弹簧圈闭塞载瘤动脉。结果栓塞程度:致密栓塞48个(64.9%。48/74),90%以上栓塞11个(14.9%,11/74),疏松(90%以下)栓塞15个(20.3%,15/74)。术中动脉瘤破裂出血4例(5.3%,4/76),2例死亡。结论电解可脱性弹簧圈栓塞颅内动脉瘤具有微创、安全、效果可靠等优点。采用微导丝辅助瘤颈成形技术、瘤颈重塑形技术、血管内支架等方法,可以明显提高宽颈动脉瘤的致密栓塞率和减少脑梗死并发症发生。     

Endovascular Treatment of Wide-Necked Intracranial Aneurysms : Techniques and Outcomes in 15 Patients

Objective

It is technically difficult to treat wide-necked intracranial aneurysms by the endovascular method. Various tools and techniques have been introduced to overcome the related technical limitations. The purpose of this study was to evaluate the radiologic and clinical results of wide-necked intracranial aneurysm treatment using the endovascular method.

Methods

Fifteen aneurysms in 15 patients were treated by the endovascular method from October 2009 to August 2010. Seven patients presented with subarachnoid hemorrhage (SAH), seven patients had unruptured aneurysms, and one patient had an intracerebral hemorrhage and intraventricular hemorrhage due to an incompletely clipped aneurysm. The mean dome-to-neck ratio was 1.1 (range, 0.6-1.7) and the mean height-to-neck ratio was 1.1 (range, 0.6-2.0). We used double microcatheters instead of a stent or a balloon for the first trial. When we failed to make a stable coil frame with two coils, we used a stent-assisted technique.

Results

All aneurysms were successfully embolized. Eleven aneurysms (73%) were embolized by the double microcatheter technique without stent insertion, and four aneurysms (27%) were treated by stent-assisted coil embolization. One case had subclinical procedure-related intraoperative hemorrhage. Another case had procedure-related thromboembolism in the left distal anterior cerebral artery. During the follow-up period, one patient (7%) had a recanalized aneurysmal neck 12 months after coil embolization. The recurrent aneurysm was treated by stent-assisted coil embolization.

Conclusion

We successfully treated 15 wide-necked intracranial aneurysms by the endovascular method. More clinical data with longer follow-up periods are needed to establish the use of endovascular treatment for wide-necked aneurysm.     

支架辅助弹簧圈治疗颅内复杂动脉瘤

目的探讨支架辅助弹簧圈治疗颅内复杂动脉瘤的方法和疗效。方法本组17例复杂颅内动脉瘤,1例采用2枚支架重叠置入动脉瘤段载瘤动脉内,16例经支架网眼送入弹簧圈行瘤腔栓塞。结果17例置入支架20枚,其中1例栓塞后出现肢体轻度麻木无力,对症处理后恢复;7例夹层动脉瘤和1例梭形动脉瘤疏松填塞。随访6￣24个月。DSA复查,示8例动脉瘤消失,1例发现置入支架上段又出现夹层动脉瘤,再次置入支架1枚及弹簧圈栓塞后,动脉瘤消失。1例置入2枚支架者1年后MRA复查示动脉瘤缩小70%。1例栓塞后2个月出现短暂性脑缺血发作者,行TCD检查,发现支架段血管狭窄,服抗凝药继续观察;其余6例行MRA、CTA检查未见动脉瘤复发。结论支架辅助弹簧圈治疗颅内复杂动脉瘤是行之有效的方法。     

Complications of Neuroform Stent in Endovascular Treatment of Intracranial Aneurysms

Background  The Neuroform stent can help in the treatment of difficult, wide-necked intracranial aneurysms. The objective of our study is to report some of the challenges associated with the Neuroform stent in the treatment of intracranial aneurysms. Methods  From January 2003 to August 2006, consecutive patients treated with Neuroform stent for intracranial aneurysms were prospectively enrolled. Information on patient demographics, cerebrovascular risk factors, aneurysm size and location were collected. Technical and clinical complications as well as clinical outcomes were measured. Data were analyzed retrospectively using SPSS software version 11.5. Results  Successful deployment of the stent, in the target artery, was achieved in 65/67 (97%) patients. Stent deployment failed in two cases and the migration of stent developed in one during coiling. Postoperative thromboembolic events developed in three patients. These three patients possessed hyperactive platelets, and were treated with intravenous eptifibatide. Intraoperative rupture of aneurysm developed in one patient, which was secured by subsequent coiling. Majority of the patients had good outcomes GOS (Glasgow Outcome Score) 1 or NIHSS (National Institute of Health Stroke Scale) 0 in 63/67 (94%), GOS 2 or NIHSS 2 in one patient and GOS 3 or NIHSS 4 was observed in three cases. Conclusion  Despite a low rate of intraoperative complications, post-procedural thromboembolic events were common in Neuroform stent-treated patients, which might be associated with hyperactive platelets. Further studies are warranted to identify any potential relationship between post-stent hyperactive platelets and thromboembolism.     

颅内外动脉狭窄合并颅内无症状动脉瘤的血管内治疗策略研究

目的 探索颅内外动脉狭窄合并颅内无症状动脉瘤的安全和有效的血管内治疗策略。 方法 回顾性分析北京天坛医院急诊介入科2012年9月～2013年8月收住的因颅内外动脉狭窄拟行支 架治疗且合并颅内无症状动脉瘤的患者26例。对其临床、影像学资料、治疗措施及结果、并发症及预 后等进行分析。 结果 26例患者共发现≥70%的狭窄或闭塞病变54处,动脉瘤30枚（非同流域16枚,狭窄后7枚,狭窄 处3枚,狭窄前4枚）。26例患者中21例实施了狭窄病变的支架置入术,共干预25个狭窄/闭塞病变,技 术成功率100%。选择个体化的动脉瘤干预措施：16例患者的17枚动脉瘤（非同流域、直径＜5 mm、 夹层）建议随访观察;2例患者的2枚动脉瘤（直径＞5 mm、形状不规则）择期行栓塞术;5例患者的 6枚动脉瘤（狭窄后、狭窄处、多发性、直径＞5 mm、后交通段）同期行栓塞术或支架覆盖;3例患者 的5枚动脉瘤（狭窄后、分叶状、多发性、直径＞5 mm）建议介入治疗但因家属拒绝手术等原因选择随 访观察。术后发生脑室出血1例。临床随访10～21个月,所有患者均预后良好,仅发现无症状性支架内 再狭窄1例。 结论 颅内外动脉狭窄合并颅内无症状动脉瘤时根据动脉瘤与狭窄病变的位置关系,动脉瘤大小、 形态、位置、数量和患者情况等综合分析后给予个体化血管内治疗安全、有效。     

高原地区颅内未破裂宽颈动脉瘤支架辅助弹簧圈栓塞治疗3年转归及与药物治疗相关性分析

目的 观察使用支架辅助弹簧圈栓塞治疗高原地区颅内未破裂宽颈动脉瘤患者的长期预后。 方法 对2007年-2011年在青海省人民医院完成且接受随访的32例支架辅助弹簧圈栓塞颅内未破裂 宽颈动脉瘤的久居高原患者,术后3年进行数字减影血管造影（digital subtraction angiography,DSA）明 确支架内狭窄发生率、动脉瘤复发情况。调查术后抗血小板治疗情况。 结果 32例患者中出现不同程度的支架内狭窄5例（15.6%）,均为术后未规律服用阿司匹林患者。动 脉瘤复发6例（18.8%）,其中2例（6.3%）为小型前交通动脉瘤,患者动脉瘤体部分显影;4例（12.5%） 为超过1.5 cm的颈内动脉虹吸段的大型动脉瘤。3年随访期内无一例患者因栓塞后动脉瘤破裂。 结论 支架辅助弹簧圈栓塞治疗高原颅内未破裂宽颈动脉瘤术式有效、可行,复发率较低,支架内 狭窄发生率与术后抗血小板治疗不规范可能有关。     

破裂颅内动脉瘤的血管内治疗

目的分析总结破裂的颅内动脉瘤血管内治疗的效果及特点。方法24例患者术前头部CT或MRI检查均为自发性蛛网膜下腔出血，DSA检查确诊为颅内动脉瘤，共28个，其中1例患者有3个动脉瘤，2例患者各有2个动脉瘤。动脉瘤直径2～5mm10个，6-15mm16个，16～25mm2个。Hunt～Hess分级Ⅰ级5例，Ⅱ级8例，Ⅲ级8例，Ⅳ级2例，Ⅴ级1例。24例动脉瘤均采用血管内栓塞治疗，其中1例患者的3个动脉瘤栓塞了2个，另1个行手术夹闭。结果临床治愈21例，偏瘫1例，死亡2例。术后随访3-24个月，存活22例均恢复良好，无再出血发生。结论血管内栓塞治疗颅内动脉瘤效果满意，并发症少，残死率低。     

颅内动脉瘤的显微手术治疗

目的 探讨颅内动脉瘤手术治疗的时机和术中注意事项。方法 回顾分析应用显微神经外科技术对64例71枚动脉瘤进行的直视手术及其疗效。结果 8枚动脉瘤夹闭后切除,1枚梭型动脉瘤作包裹术,其余均作夹闭术。术中动脉瘤破裂13例。Hunt Ⅱ级以内动脉瘤的良好率为94.7％(36/38),无死亡,Ⅲ级以内动脉瘤的良好率为88.1％(52/59),死亡率为3.4％(2/59)。结论 显微神经外科手术是颅内动脉瘤有效、安全的治疗方法,但应选择适当的时机进行。     

Enterprise支架在严重症状性颅内动脉粥样硬化病变血管内治疗中的应用

目的 观察超说明书Enterprise支架在严重颅内动脉粥样硬化狭窄（intracranial atherosclerotic stenosis, ICAS）病变中应用的有效性及安全性。 方法 回顾性纳入单中心由颅内不同部位动脉粥样硬化狭窄性或闭塞病变引起的、3个月内曾发生 低灌注脑梗死或TIA的症状性患者,所有患者经DSA检查确定血管狭窄程度,狭窄率为70%～100%。给 予Enterprise支架置入,采用门诊或电话随访。观察手术技术成功（前向血流mTICI 2b/3级）率、狭窄程 度的变化、围手术期（术后1周内）卒中事件的发生和死亡以及远期血管再狭窄率。 结果 共纳入36例患者,34例为≥70%的狭窄性病变,2例为闭塞病变。36例患者共置入Enterprise支架 38枚,其中2例串联病变置入支架4枚。手术技术成功率94.44%（34/36）,狭窄率从（89.21±5.13）% 减至（23.56±3.57）%（P =0.021）。围手术期缺血性卒中2例（5.6%）,均为穿支病变。平均随访 12.37±3.11个月,无死亡及复发病例。20例（55.56%）患者于术后18.25±2.13个月复查了头颅CTA,其中 1例基底动脉及椎动脉V4段串联病变者,术后8个月CTA复查显示V4残余狭窄消失,但基底动脉残余狭窄 加重约20%,其余患者残余狭窄均消失。 结论 Enterprise支架用于动脉粥样硬化性颅内动脉狭窄性病变的治疗可能是安全、有效的,但仍需 随机对照研究证实。     

颅内大型动脉瘤的血管内治疗及随访

目的探讨血管内治疗大型动脉瘤的方法、效果及其并发症的防治。方法回顾性分析2000年1月至2006年12月间我科经血管内治疗的109例颅内人型动脉瘤患者的临床资料。结果患者术后恢复良好99例（90．8％）,功能障碍8例（7.3％）,死亡2例（1．8％）。101例（共105枚）大型动脉瘤患者接受血管内栓塞治疗,其中100％闭塞73枚,90％-95％闭塞21枚,80％闭塞11枚。8例患者行载瘤动脉闭塞术。107例术后随访8～36个月无出血病例。58例患者经血管造影或MRA随访,9枚动脉瘤再通。结论血管内栓塞治疗颅内大型动脉瘤安全、有效,中期疗效肯定,长期随访结果尚待进一步完善。     

显微手术治疗颅内动脉瘤

目的探讨经翼点入路显微手术治疗颅内动脉瘤的方法。方法在气管插管全麻及控制性低血压下手术,采用Yasargil翼点入路,应用显微外科技术对52例颅内动脉瘤患者行动脉瘤颈夹闭或包裹术(其中8例应用内镜辅助)。结果本组48例行瘤颈夹闭术,4例行包裹术,术中动脉瘤破裂10例。术后45例治愈出院,4例有不同程度的偏瘫,3例死亡。结论熟练的显微外科技术是颅内动脉瘤手术成功的重要保障;预见性采用控制性低血压及暂时阻断载瘤动脉是术中动脉瘤破裂出血的重要应急措施;应用内镜辅助可更确切的夹闭动脉瘤颈,降低术后并发症的发生率。     

颅内微型动脉瘤诊断和治疗的临床研究

目的探讨颅内微型动脉瘤的临床特征和治疗方法。方法经DSA确诊的颅内微型动脉瘤（直径〈3mm）21例（22枚）中，1例放弃外科治疗；9例行开颅手术．其中动脉瘤夹闭5例，包裹3例（1例电凝动脉瘤后动脉瘤消失），孤立载瘤动脉（颈内动脉）1例；11例行血管内治疗，其中1例小脑上动脉瘤采用NBCA胶栓塞，10例（11枚动脉瘤）采用微弹簧圈栓塞，其中采用瘤颈成型技术6例（支架辅助2例，双导管技术3例，导丝辅助技术1例）。结果行开颅手术的9例中，死亡1例，治愈4例，好转2例，残废2例；术中动脉瘤破裂2例。行血管内治疗手术的11例中，死亡1例，治愈7例，好转1例，残废2例。血管内栓塞术中动脉瘤破裂2例。结论3D—DSA是诊断颅内微型动脉瘤最有价值的方法，手术和栓塞治疗的风险均较高，但采用适当的技术仍可以取得好的效果。     

Endovascular Treatment of Ruptured Pericallosal Artery Aneurysms

Objective

Aneurysms arising from the pericallosal artery (PA) are uncommon and challenging to treat. The aim of this study was to report our experiences of the endovascular treatment of ruptured PA aneurysms.

Methods

From September 2003 to December 2013, 30 ruptured PA aneurysms in 30 patients were treated at our institution via an endovascular approach. Procedural data, clinical and angiographic results were retrospectively reviewed.

Results

Regarding immediate angiographic control, complete occlusion was achieved in 21 (70.0%) patients and near-complete occlusion in 9 (30.0%). Eight procedure-related complications occurred, including intraprocedural rupture and early rebleeding in three each, and thromboembolic event in two. At last follow-up, 18 patients were independent with a modified Rankin Scale (mRS) score of 0-2, and the other 12 were either dependent or had expired (mRS score, 3-6). Adjacent hematoma was found to be associated with an increased risk of poor clinical outcome. Seventeen of 23 surviving patients underwent follow-up conventional angiography (mean, 16.5 months). Results showed stable occlusion in 14 (82.4%), minor recanalization in two (11.8%), and major recanalization, which required recoiling, in one (5.9%).

Conclusion

Our experiences demonstrate that endovascular treatment for a ruptured PA aneurysms is both feasible and effective. However, periprocedural rebleedings were found to occur far more often (20.0%) than is generally suspected and to be associated with preoperative contrast retention. Analysis showed existing adjacent hematoma is predictive of a poor clinical outcome.     

颅内动脉狭窄及治疗进展

颅内动脉粥样硬化性狭窄是卒中的高危因素。在有症状的卒中患者中8%～10%有颅内动脉粥样硬化性狭窄。颅内动脉粥样硬化性狭窄年卒中发生率约为10%～24%。颅内动脉粥样硬化性狭窄的颅外/颅内动脉搭桥及药物治疗被证明是不成功的,支架置入是一种替代治疗方法,而且被证明是可取的、安全有效的治疗方法。     

血管内栓塞治疗颅内动脉瘤围手术期并发症

目的总结血管内栓塞治疗颅内动脉瘤围手术期并发症,并讨论其防治方法。方法对184例血管内治疗的颅内动脉瘤患者的临床资料进行回顾性分析。结果36例患者在围手术期出现并发症,包括动脉瘤破裂出血6例,血管内栓塞6例,脑积水21例,其它并发症3例。其中死亡5例,肢体功能障碍2例。结论血管内栓塞、动脉瘤破裂出血和脑积水是颅内动脉瘤血管内治疗围手术期常见并发症,要积极防治,熟悉动脉瘤和载瘤动脉的解剖特点,掌握栓塞技巧和手术操作要求,早期引流蛛网膜下腔积血,有助于减少并发症的发生,提高患者治愈率。     

Comparative Cost Analysis for Surgical and Endovascular Treatment of Unruptured Intracranial Aneurysms in South Korea

Objective

A cost comparison of the surgical clipping and endovascular coiling of unruptured intracranial aneurysms (UIAs), and the identification of the principal cost determinants of these treatments.

Methods

This study conducted a retrospective review of data from a series of patients who underwent surgical clipping or endovascular coiling of UIAs between January 2011 and May 2014. The medical records, radiological data, and hospital cost data were all examined.

Results

When comparing the total hospital costs for surgical clipping of a single UIA (n=188) and endovascular coiling of a single UIA (n=188), surgical treatment [mean±standard deviation (SD) : ₩8,280,000±1,490,000] resulted in significantly lower total hospital costs than endovascular treatment (mean±SD : ₩11,700,000±3,050,000, p<0.001). In a multi regression analysis, the factors significantly associated with the total hospital costs for endovascular treatment were the aneurysm diameter (p<0.001) and patient age (p=0.014). For the endovascular group, a Pearson correlation analysis revealed a strong positive correlation (r=0.77) between the aneurysm diameter and the total hospital costs, while a simple linear regression provided the equation, y (₩)=6,658,630+855,250x (mm), where y represents the total hospital costs and x is the aneurysm diameter.

Conclusion

In South Korea, the total hospital costs for the surgical clipping of UIAs were found to be lower than those for endovascular coiling when the surgical results were favorable without significant complications. Plus, a strong positive correlation was noted between an increase in the aneurysm diameter and a dramatic increase in the costs of endovascular coiling.     

Long-Term Effects on Preventing Stroke after Endovascular Treatment or Bypass Surgery for Intracranial Arterial Stenosis

Background: Intracranial arterial stenosis (ICAS) is an important cause of ischemic stroke worldwide due to its higher risk of recurrence with medical therapy. Although some large randomized studies failed to show the superiority of surgical treatment compared with medical therapy, the results of medical therapy are not sufficient. There are patients who still benefit from surgical treatment. This retrospective analysis aimed to evaluate the long-term efficacy of surgical therapy with percutaneous transluminal angioplasty and/or stenting (PTA/PTAS) or extracranial-intracranial (EC/IC) bypass surgery for patients with ICAS. Methods: Between October 2005 and December 2016, 55 ICAS patients were treated with PTA/PTAS or EC-IC bypass surgery. Their electronic medical records were retrospectively reviewed and analyzed. The primary outcome was all adverse events beyond 30 days after a revascularization procedure. Results: We performed 21 cases (35%) of PTA, 4 cases (7%) of PTAS, and 34 cases (58%) of EC-IC bypass surgery and the median follow-up duration was 66 months (range 1-144 months). The occurrence rate of the primary outcome was 10.2% and only 1 patient (1.8%) experienced ipsilateral disabling ischemic stroke beyond 30 days. The long-term functional independent survival rate was 83.6%. Conclusions: We demonstrated a long-term favorable outcome of combined surgical intervention for ICAS patients with PTA/PTAS and EC-IC bypass surgery, and the result was better than previously reported outcomes of medical therapy. Additional multicenter studies are required to draw firm conclusions on the efficacy of reduction of recurrent stroke in patients with ICAS.     

Outcomes of Stent-Assisted Coiling Using the Neuroform Atlas Stent in Unruptured Wide-Necked Intracranial Aneurysms

ObjectiveAlthough stent-assisted coiling (SAC) has been reported to be safe and effective in treating wide-necked aneurysms, the technique has procedure-related complications. Thus, we reported our experiences of SAC using the Neuroform Atlas stent in treating wide-necked aneurysms and evaluated the incidence of and risk factors for procedure-related complications. MethodsFrom March 2018 to August 2019, we treated 130 unruptured wide-necked aneurysms in 123 patients with Neuroform Atlas stents. Angiographic results and clinical outcomes were reviewed retrospectively. Clinical and angiographic follow-up were performed in all cases (mean, 12.4 months) after the procedure. ResultsThere were eight cases (6.2%) of procedure-related complications (two dissections, five thromboembolisms, and one hemorrhage) and two (1.5%) of delayed complications (one ischemia and one hemorrhage). There was one case (0.8%) of failure of stent deployment and one (0.8%) of suboptimal positioning of the stent. Follow-up angiography showed complete obliteration in 103 (79.2%), residual neck in 16 (12.3%), and residual aneurysm in 11 cases (8.5%). Aneurysm locations in the middle cerebral artery (odds ratio [OR], 2.211; p=0.046) and the anterior communicating artery (OR, 2.850; p=0.039) were associated with procedure-related complications on univariate analysis. However, no independent risk factor for procedure-related complications was noted in multivariate analysis. ConclusionThe Neuroform Atlas showed a high rate of technical success. Good clinical and radiographic outcomes in early follow-up suggests that the device is feasible and safe. SAC of aneurysms on the middle cerebral artery or anterior communicating artery may require more attention to prevent possible procedure-related complications.     

The Fate of Partially Thrombosed Intracranial Aneurysms Treated with Endovascular Intervention

ObjectiveThe fate of partially thrombosed intracranial aneurysms (PTIAs) is not well known after endovascular treatment. The authors aimed to analyze the treatment outcomes of PTIAs. MethodsWe retrospectively reviewed the medical records of 27 PTIAs treated with endovascular intervention between January 1999 and March 2018. Twenty-one aneurysms were treated with intraluminal embolization (ILE), and six were treated with parent artery occlusion (PAO) with or without bypass surgery. Radiological results, clinical outcomes and risk factors for major recurrence were assessed. ResultsThe initial clinical status was similar in both groups; however, the last status was better in the ILE group than in the PAO group (p=0.049). Neurological deterioration resulted from mass effect in one case and rupture in one after ILE, and mass effect in two and perforator infarction in one after PAO. Twenty cases (94.2%) in the ILE group initially achieved complete occlusion or residual neck status. However, 13 cases (61.9%) showed major recurrence, the major causes of which included coil migration or compaction. Seven cases (33.3%) ultimately achieved residual sac status after repeat treatment. In the PAO group, all initially showed complete occlusion or a residual neck, and just one case ultimately had a residual sac. Two cases showed major recurrence, the cause of which was incomplete PAO. Aneurysm wall calcification was the only significantly protective factor against major recurrence (odds ratio, 36.12; 95% confidence interval, 1.85 to 705.18; p=0.018). ConclusionComplete PAO of PTIAs is the best option if treatment-related complications can be minimized. Simple fluoroscopy is a useful imaging modality because of the recurrence pattern.