经单侧6F导引导管应用球囊辅助技术栓塞脑动脉瘤的体会

目的:探讨经单侧6F导引导管应用球囊辅助技术治疗脑动脉瘤的临床应用价值。方法:对15例脑动脉瘤患者常规经股动脉穿刺置入6F动脉鞘,先使用5F诊断造影管行全脑血管造影术,然后将6F Envoy导引导管置于载瘤的颈内动脉或椎动脉,借助于微导丝将微导管和球囊导管通过Y形阀或蝶形阀一起送入导引导管至动脉瘤处.在球囊保护下行动脉瘤栓塞术。结果:本组15例均成功通过单侧6F导引导管置入球囊导管和输送弹簧圈的微导管。操作顺利,无手术死亡及相关并发症。结论:经单侧6F导引导管可以顺利应用球囊辅助技术辅助栓塞治疗脑动脉瘤,操作安全、简便.可在临床推广使用。     

Balloon-assisted coiling through a single 6F guiding catheter

The new version of the 6F Envoy guiding catheter, with its enlarged inner diameter of 0.070 inch, is capable of simultaneously accommodating both a 0.014-inch microcatheter and a balloon microcatheter for balloon-assisted coiling (BAC). We report our experience using this guiding catheter for access in BAC in 48 patients. The guiding catheter allowed for easy manipulations of 2 microcatheters, while providing sufficient quality of control angiograms during the procedure. In cases in which BAC is indicated, a larger guiding catheter (7F) or the commonly used bifemoral approach is no longer necessary, making the procedure technically simpler for the operator and less traumatic to the vessel wall.     

A 6F guide sheath for endovascular treatment of intracranial aneurysms

Introduction Stable insertion of guide catheters via the femoral route can prove difficult because of tortuous vasculature leading to failure of endovascular treatment of intracranial aneurysms. Methods and results We report our experience using a long braided introducer sheath (6F Terumo Destination) with an inner diameter of 0.087 inches. It allowed the simultaneous use of multiple catheters or adjunctive techniques (balloon-assisted or stent-assisted coiling) while providing excellent support in 60 procedures involving coiling of anterior circulation aneurysms. Conclusion The use of a long introducer sheath, by enhancing stability in the aortic arch and supraaortic vessels, provides another solution to the problem of vascular tortuosity that hinders endovascular treatment of intracranial lesions.     

Thromboembolic events associated with balloon-assisted coil embolization: evaluation with diffusion-weighted MR imaging

BACKGROUND AND PURPOSE: Thromboembolic events may occur during or after the treatment of intracranial aneurysms with Guglielmi detachable coils (GDCs). The purpose of this study was to determine the frequency of thromboembolic events associated with balloon-assisted coil placement and to investigate possible risk factors for these events during balloon-assisted coil placement and embolization. METHODS: Twenty patients with cerebral aneurysms treated with balloon-assisted coil placement and embolization at our institution were included. All patients underwent diffusion-weighted (DW) imaging within 6 hours after the procedure. Two neuroradiologists reviewed all DW images to detect ischemic lesions. RESULTS: Hyperintense lesions compatible with thromboembolic events were detected on DW images of four (20%) patients. Three lesions were in the territory of posterior circulation, and one was in the territory of anterior circulation. The occurrence of new lesions was strongly associated with the number of times the microcatheter or coil was repositioned and removed and with the size of the aneurysmal neck (P < .01). DW imaging findings did not suggest a strong correlation between the occurrence of new ischemic lesions and potential risk factors (maximum balloon inflation time, number of times the balloon was inflated, etc.) associated with balloon-assisted coil placement and embolization (P > .05). CONCLUSION: The risk of thromboembolic events during the treatment of intracranial aneurysms with balloon-assisted techniques is not more significant than when conventional GDC techniques are used. The only variables found to influence this risk during or after balloon-assisted coil placement were microcatheter repositioning, coil removal and repositioning, and size of the aneurysmal neck.     

Intraarterial administration of Abciximab for thromboembolic events occurring during aneurysm coil placement

BACKGROUND AND PURPOSE: Platelet-derived thrombi may occur during intracranial aneurysm coiling. We report a series of 13 patients treated with intraarterial Abciximab for thrombus formation complicating aneurysm coiling. METHODS: Four patients were treated for acutely ruptured aneurysms. Three procedures consisted of the retreatment of previously coiled aneurysms. Six patients had asymptomatic untreated aneurysms. Abciximab was administered intraarterially through a microcatheter as a bolus of 4-10 mg over a period of 10-20 minutes. All patients underwent postthrombolysis control angiography. They also underwent immediate pre- and postoperative cranial CT. RESULTS: In 10/13 cases, the thrombi developed without coil protrusion into the parent artery. In one case, the thrombus was generated from the guiding catheter and embolized remote from the aneurysm site. In one case, the thrombus developed before any coil placement. In another patient, a coil loop protruded into the parent artery favoring a heightened thrombotic state. Arterial thrombi were totally occlusive in two patients, whereas in the remaining 11 cases, the thrombi were not totally obstructive. Complete recanalization was achieved in 92% (12/13) of cases within 20-30 minutes. Incomplete arterial reopening was noted in one case, in which a thrombus fragment embolized distally, causing cerebral infarction. There were no Abciximab-related intracranial hemorrhages. CONCLUSION: Intraarterial Abciximab was effective in this series for the treatment of thrombotic complications occurring during aneurysm coiling.     

A new self-expandable nitinol stent for the treatment of wide-neck aneurysms: initial clinical experience

BACKGROUND AND PURPOSE: Stent systems for intracranial use are continuously improved. We report our initial experience using a new self-expanding easy-to-place nitinol stent (Enterprise) in the treatment of wide-neck intracranial aneurysms.MATERIALS AND METHODS: Between January and October 2007, 16 aneurysms in 15 patients were treated with stent assistance. Aneurysm size was a mean of 13.2 mm (median, 12 mm; range, 7–30 mm). Eight aneurysms had reopened after prior coiling, and 8 aneurysms were primarily treated, 1 after acute subarachnoid hemorrhage. Response to antiplatelet premedication was tested with a P2Y12 assay before stent placement. On a 3D angiographic workstation, stent placement was simulated to assess vessel caliber and appropriate stent length.RESULTS: In all aneurysms, the stent could be placed at the exact location as predicted from the computer simulation. Stent placement proved to be technically easy without the need for recapture in all patients. Although placement of the microcatheter through the stent struts and subsequent coil placement was challenging in some patients, coiling after stent placement resulted in complete or near-complete occlusion in all aneurysms. There were no technical or clinical complications. At 6 months, angiographic follow-up in 14 aneurysms revealed 4 aneurysms recanalized to 80% occlusion, 3 of which were additionally coiled.CONCLUSION: In this small series, delivery and deployment of the Enterprise stent was technically easy. There were no technical or clinical complications. The device was valuable in the treatment of wide-neck aneurysms. The need for antiplatelet medication in patients treated with this and other stents remains a significant disadvantage.

Endovascular coil embolization of wide-neck intracranial aneurysms is technically challenging. Several treatment strategies are available to prevent coil migration into the parent vessel. The most widely used technique is balloon-assisted treatment, in which a balloon is temporarily inflated across the aneurysm neck during coil insertion.^1,2 A permanent neck-bridge device (TriSpan; Boston Scientific, Natick, Mass) may be used to prevent coil migration in wide-neck bifurcation aneurysms.^3,4 In recent years, stents for intracranial use became available. The first-generation stents were balloon expandable (INX/AVE; Medtronic, Santa Rosa, Calif), but limited flexibility was a major drawback. Later, the first self-expandable stents with an open or closed cell design became available for intracranial use.^5,6 With some stent systems, the microcatheter has to be exchanged for the stent over a 300-cm microguidewire. The new Enterprise stent (Cordis Neurovascular, Miami Lakes, Fla) is a highly flexible nitinol stent, which can be delivered through a standard microcatheter, which is technically easier than the exchange procedure.^7–9In this study, we report our initial clinical experience with this new stent system in the treatment of 16 wide-neck intracranial aneurysms.     

Are the configuration and neck morphology of experimental aneurysms predictable? A technical approach

Aneurysm configuration and neck morphology are important factors in the decision for cerebral aneurysm therapy, i.e., clipping versus coiling. The aim of our study was to create various aneurysm configurations in a predictable and reproducible way in an animal model. In our recently proposed endovascular approach to produce bifurcation aneurysms in the rabbit, the right common carotid artery (CCA) is surgically exposed and distally ligated, and a sheath is advanced retrogradely into the CCA, the base of which is proximally occluded using a Fogarty balloon. Subsequently, elastase is injected via a microcatheter that is placed directly distal to the balloon and allowed to incubate for 20 min. After removal of the sheath, saccular aneurysms begin to form within 2 weeks. For greater variability in aneurysm size and neck morphology, we modified two parameters of this formerly established elastase-induced aneurysm model—the distance between the balloon and sheath and the level of balloon position—before the elastase was endoluminally incubated in 15 rabbits. Three weeks after aneurysm induction, the size and configuration of the aneurysms were controlled using DSA. Our results confirm that balloon occlusion in the brachiocephalic trunk results in broad-based aneurysms, whereas balloon occlusion in the CCA gives rise to circumscribed aneurysm necks. By increasing the distance between the balloon and sheath, the rabbits developed significantly larger aneurysms. The balloon-sheath distance and the level of balloon occlusion proved to be parameters whose modifications result in predictable and reproducible aneurysm variants that can be used for the testing of endovascular devices.     

The sheeping technique or how to avoid exchange maneuvers

Introduction

The arteries of bifurcation aneurysms are sometimes so angulated or tortuous that an exchange maneuver is necessary to catheterize them with a balloon or stent delivery catheter. Because of the risk of distal wire perforation associated with exchange maneuvers, we sought to find an alternative technique.

Methods

Our experience shows that a microcatheter tends to preferentially follow a previously placed microcatheter, even if the initial catheterization might be challenging. Accessing an artery with two microcatheters simultaneously may thus be an alternative to an exchange maneuver. Because of this tendency for catheters to behave like sheep following one another, we named this method the sheeping technique (ST). The ST consists of (a) first placing a 1.7 French microcatheter into the division branch requiring balloon or stent protection to straighten the course of the arteries in order to facilitate and (b) positioning in the same artery of a larger and stiffer balloon or stent microcatheter. Once the second balloon or stent microcatheter is in place, the first microcatheter can be pulled back and used to coil the aneurysm.

Results

Between January 2009 and December 2012, The ST was successfully used in 208/246 procedures (85 %). Conversion to an exchange maneuver was necessary in 38/246 (15 %). There were no arterial perforations or ischemic events related to the handling of both microcatheters.

Conclusion

The sheeping technique may improve safety by replacing the need for an exchange maneuver during difficult balloon- or stent-assisted coiling.     

Utility of balloon-assisted Guglielmi detachable coiling in the treatment of 49 cerebral aneurysms: a retrospective, multicenter study

BACKGROUND AND PURPOSE: The management of wide-necked aneurysms or aneurysms with a neck-to-body ratio close to 1 is a difficult challenge for the interventional radiologist because of the risk of coil migration or coil protrusion into the parent vessel. Our objective was to evaluate the efficacy and safety of balloon-assisted coiling as well as the follow-up results of occlusion for those difficult aneurysms in which conventional treatment with Guglielmi detachable coils (GDCs) had failed. METHODS: A nondetachable balloon was used in 49 procedures performed in 44 patients (35 women and nine men) who underwent GDC coiling of aneurysms. Every aneurysm had either a wide neck or a sac diameter/neck size ratio (SNR) of 1.5 or less. RESULTS: In four (8%) of the procedures, balloon placement failed, leaving a total of 45 aneurysms treated with balloon-assisted coiling. Final results consisted of total occlusion in 30 cases (67%), subtotal occlusion in 11 cases (24%), and incomplete occlusion in four cases (9%). We found a correlation between the diameter of the sac and the occlusion rate, but not between the size of the neck or the SNR and the occlusion rate. Two thromboembolic complications occurred, but neither had clinical consequences. No aneurysmal rupture was observed during treatment. Final angiographic follow-up time ranged from 3 months to 5 years (mean, 16 months). CONCLUSION: Balloon-assisted coiling is an important adjunct in the treatment of aneurysms with a wide neck or low SNR. In our experience, this technique allowed safe and efficient treatment of aneurysms when conventional GDC treatment had failed.     

Central Vein Dilatation Prior to Concomitant Port Implantation

Implantation of subcutaneous port systems is routinely performed in patients requiring repeated long-term infusion therapy. Ultrasound- and fluoroscopy-guided implantation under local anesthesia is broadly established in interventional radiology and has decreased the rate of complications compared to the surgical approach. In addition, interventional radiology offers the unique possibility of simultaneous management of venous occlusion. We present a technique for recanalization of central venous occlusion and angioplasty combined with port placement in a single intervention which we performed in two patients. Surgical port placement was impossible owing to occlusion of the superior vena cava following placement of a cardiac pacemaker and occlusion of multiple central veins due to paraneoplastic coagulopathy, respectively. In both cases the affected vessel segments were dilated with balloon catheters and the port systems were placed thereafter. After successful dilatation, the venous access was secured with a 25-cm-long, 8-Fr introducer sheath, a subcutaneous pocket prepared, and the port catheter tunneled to the venipuncture site. The port catheter was introduced through the sheath with the proximal end connected to a 5-Fr catheter. This catheter was pulled through the tunnel in order to preserve the tunnel and, at the same time, allow safe removal of the long sheath over the wire. The port system functioned well in both cases. The combination of recanalization and port placement in a single intervention is a straightforward alternative for patients with central venous occlusion that can only be offered by interventional radiology.     

Distal-tip shape-consistency testing of steam-shaped microcatheters suitable for cerebral aneurysm coil placement

BACKGROUND AND PURPOSE: Although the selection of microcatheter for endovascular aneurysmal treatment is one important factor in patient outcome, the use of steam shaping for achieving safe entry and stability during coil placement has not, to our knowledge, been systematically evaluated. The goal of this study was to compare the durability of distal microcatheter steam shaping in five different catheters with typical intraprocedural stresses that are similar to those encountered during aneurysm coil placement. METHODS: Distal tips of microcatheters were shaped into a 90 degrees turn with distal straight-segment lengths of 3, 5, or 7 mm by using steam, performed according to the instructions for use included with each catheter. In a water bath kept at body temperature, the changes in catheter tip angle were recorded and measured following microcatheter insertion into a guiding catheter, microguidewire insertion through the microcatheter, and Guglielmi detachable coil (GDC) placement through the microcatheter. RESULTS: The degree of distal microcatheter straightening with typical intraprocedural manipulations was more pronounced on braided microcatheters and on microcatheters with 3- or 5-mm distal-shaped segments. The degree of spontaneous recovery of the initially steamed shape was more pronounced with nonbraided catheters. The most significant single variable contributing to straightening of a steam-shaped catheter tip was the effect of microguidewire insertion. The catheter-tip straightening effect encountered with inserting GDCs was less than that encountered with microguidewire insertion. We demonstrated that the decreased catheter-tip angle encountered with a large-magnitude straightening stress spontaneously recovered once the stress was removed or when it was reduced to a smaller magnitude stress. CONCLUSION: Our study shows that, although braided microcatheters are suitable for maintaining durable configurations when long distal-tip lengths are permissible, nonbraided microcatheters demonstrate the most durable distal-tip configurations when short distal-tip lengths are called for. This may be one of significant factors in catheter choice for endovascular treatment of aneurysm.     

Thrombogenicity of hydrophilic and nonhydrophilic microcatheters and guiding catheters.

PURPOSETo assess in a swine model the in vivo thrombogenicity of various microcatheters and guiding catheters as a function of catheter material, catheter coating, and duration of implantation.METHODSMicrocatheters (Tracker 18 and Fastracker 18, Target Therapeutics, Fremont, Calif; Magic 1.8, Balt, Montmorency, France; and Transit, Cordis Endovascular Systems, Miami Lakes, Fla) were placed through 6F guiding catheters (Fasguide, Target Therapeutics, and Envoy, Cordis Endovascular Systems) into the common carotid arteries of swine for 30 minutes (short term), 90 minutes (medium term), and 35 days (long term). Guiding catheters were implanted for 5 hours. At the end of the implantation periods the catheters were retracted and fixed for scanning electron microscopy.RESULTSThe surface of the Fastracker microcatheter was devoid of debris after both short- and medium-term implantation. The Tracker microcatheter had minimal accumulation of cellular elements whereas the Transit microcatheter showed moderate accumulation of nondeformed red blood cells. Neither the Tracker nor the Transit microcatheter showed evidence of increasing debris accumulation after medium-term implantation as compared with short-term implantation. The Magic microcatheter was coated with gross thrombus after both short- and medium-term implantation. The Fasguide guiding catheter was nearly devoid of debris, while the Envoy guiding catheter had moderate thrombus formation. Long-term implantation of the Fastracker microcatheter was well tolerated whereas that of the Transit catheter resulted in vessel occlusion.CONCLUSIONSHydrophilic microcatheters and guiding catheters are less thrombogenic than their nonhydrophilic counterparts, but not all hydrophilic coatings are equally hypothrombogenic. Degree of thrombogenicity depends on catheter material rather than surface morphology. Medium-term implantation did not yield increasing thrombus formation relative to short-term implantation.     

Temporary Stent-Assisted Coil Embolization as a Treatment Option for Wide-Neck Aneurysms

BACKGROUND AND PURPOSE:Simple coil embolization is often not a feasible treatment option in wide-neck aneurysms. Stent-assisted coil embolization helps stabilize the coils within the aneurysm. Permanent placement of a stent in an intracranial vessel, however, requires long-term platelet inhibition. Temporary stent-assisted coiling is an alternative technique for the treatment of wide-neck aneurysms. To date, only case reports and small case series have been published. Our purpose was to retrospectively analyze the effectiveness and safety of temporary stent-assisted coiling in a larger cohort.MATERIALS AND METHODS:Research was performed for all patients who had undergone endovascular aneurysm treatment in our institution (University Hospital Aachen) between January 2010 and December 2015. During this period, 355 consecutive patients had undergone endovascular aneurysm treatment. We intended to treat 33 (9.2%) of them with temporary stent-assisted coiling, and they were included in this study. Incidental and acutely ruptured aneurysms were included.RESULTS:Sufficient occlusion was achieved in 97.1% of the cases. In 94%, the stent could be fully recovered. Complications occurred in 5 patients (14.7%), whereas in only 1 case was the complication seen as specific to stent-assisted coiling.CONCLUSIONS:Temporary stent-assisted coiling is an effective technique for the treatment of wide-neck aneurysms. Safety is comparable with that of stent-assisted coiling and coiling with balloon remodeling.

Simple coil embolization is often not a feasible treatment option in wide-neck aneurysms. Stent-assisted coil embolization helps stabilize the coils within the aneurysm.¹ Permanent placement of a stent in an intracranial vessel, however, requires long-term platelet inhibition. Platelet inhibition is known to be associated with a higher bleeding risk.² Particularly in patients who require further treatment in an intensive care unit, such as patients with an acute subarachnoid hemorrhage, a higher bleeding risk should be avoided. In addition, dual platelet inhibition as recommended when stents are deployed permanently, increases the risk for cerebral hemorrhage within potentially existent ischemic brain tissue due to vasospasms.³ Hence, avoiding permanent stent placement is an advantage in patients with acute SAH.In the past, several techniques have been established for the treatment of wide-neck aneurysms. Common techniques are stent-assisted coiling, balloon-assisted coiling, double microcatheter coiling, and aneurysm treatment with dedicated devices such as the Woven EndoBridge (WEB; Sequent Medical, Aliso Viejo, California) device^4,5 or the Comaneci device (Rapid Medical, Yokneam, Israel).^6,7 The combination of balloon remodeling and stent-assisted coiling is another treatment option with possible achievement of higher occlusion rates.⁸Stent-assisted coiling and balloon remodeling seem to have a comparable complication rate in the literature, ranging between 10% and 20%.^9,10Treatment of wide neck-aneurysms is also possible with flow diverter devices with an occlusion rate of about 80%.¹¹ However, with a latency of 4–12 months to aneurysm thrombosis and the need for subsequent platelet inhibition, these are not a primary option in patients with an acutely ruptured intracranial aneurysm.Another treatment option for wide-neck aneurysms is temporary stent-assisted coiling.^12,13 For this purpose, 2 microcatheters are used. The first microcatheter is used to cover the aneurysm neck and deploy the stent. The second microcatheter is advanced into the aneurysm to perform coil embolization. Advancement of the second microcatheter into the aneurysm can be performed either before deployment of the stent or after stent deployment.¹⁴ The stent is deployed to cover the aneurysm neck but is not fully released. After coil embolization has been completed, the stent is recovered (Figs 1 and ​and2).2). In the unlikely event of coil protrusion during the process of recovery of the stent, recovery is stopped, the stent is deployed again, and it is released for permanent implantation. Temporary stent-assisted coiling is an established standard technique in our institution for the treatment of wide-neck aneurysms. Because to date, only case reports and small case series have been published, we analyzed a larger cohort of patients treated with temporary stent-assisted coiling.^12,13 Following, we present a retrospective analysis on the effectiveness and safety of temporary stent-assisted coiling.Open in a separate windowFig 1.A, An aneurysm of the anterior communicating artery before coiling. B, The same aneurysm partially coiled with a deployed Solitaire stent from the left A1 to the right A2 segment. C, The same aneurysm after complete coil embolization. The Solitaire stent has been recovered.Open in a separate windowFig 2.A, A carotid-T aneurysm before coiling. B, The same aneurysm partially coiled with the deployed Solitaire stent from the internal carotid artery to the left M1 segment. C, The same aneurysm after complete coil embolization. The Solitaire stent has been recovered.     

Modified buddy wire technique for coil embolization of posterior circulation aneurysms

Introduction In coil embolization of a posterior circulation aneurysm, tortuosity or a small vessel caliber frequently prevents placement of a guiding catheter in the vertebral artery. Even in such difficult situations, however, coil embolization is the only treatment option when the patient’s clinical condition is very poor, or the aneurysm is inaccessible by microsurgery. Methods Three patients with a posterior circulation aneurysm were treated by coil embolization with the use of a modified buddy wire technique to stabilize a guiding catheter that could not be placed into the vertebral artery. Results The guiding catheter was stabilized in the subclavian artery and the microcatheter was firmly supported. As a result, coil embolization was performed safely in all patients. There were no procedural complications. Conclusion The modified buddy wire technique could provide patients with a chance to undergo endovascular surgery despite having a tortuous or narrow vertebral artery.     

Balloon-assisted coil placement in wide-neck bifurcation aneurysms by use of a new,compliant balloon microcatheter

Two types of balloon are usually employed to perform balloon-assisted coil placement in cerebral aneurysms: oval, guide-dependent balloons for sidewall aneurysms and round balloons for bifurcation aneurysms. We report on the use of a new, more compliant, guide-dependent oval balloon microcatheter to seal wide-neck bifurcation aneurysms with coils during endovascular occlusion.     

Neurovascular Neck-Bridging device in treatment of wide-necked splenic artery aneurysms

We report the cases of 2 female patients, 45-year-old and 49-year-old, affected by wide-necked splenic aneurysm. We embolized the 2 lesions assisted by a new scaffolding neurovascular device, the Cascade Net, an innovative –occlusive remodeling device for temporary bridging in endovascular coil embolization of intracranial aneurysms. Visceral artery aneurysms are rare with an estimated prevalence of 2%-3% in imaging series and up to 10% in autopsy series. Most are asymptomatic and their diagnosis is occasionally. Aneurysm spontaneous rupture has been demonstrated in 2%-10% of cases and it can result in significant morbidity and mortality. Conservative management and open repair were the preferred treatment options for many years. Endovascular repair has been increasingly used since 2000; and the most widespread method of treatment has been coiling. Because of tortuosity of the parent artery, wide neck, and unfavorable locations at arterial branch points, 6% of Visceral and renal artery aneurysms VRAA cannot be adequately treated by simple coiling and requires parent artery remodeling through balloon occlusion, stent placement or parent vessel occlusion, leading to, in the latter situation, a compromised organ perfusion. Increasingly, balloon-assisted, and stent-assisted approaches as well as novel scaffolding neurovascular devices such as the Cascade Net, have allowed wide necked aneurysms to be bridged during endovascular treatment with smaller delivery system, averting parent artery occlusion and risk of distal embolization.     

Embolotherapy of aneurysms under temporary balloon occlusion of the neck. In vitro study of a newly designed eccentric balloon catheter

RATIONALE AND OBJECTIVES: To test embolotherapy of aneurysms in an in vitro model using standard and specially designed eccentric occlusion balloon catheters for simultaneous delivery of the embolization agent and occlusion of the neck of the aneurysm. METHODS: Two different in vitro set-ups were used: a bifurcational aneurysm and an aneurysm with a straight parent vessel segment, both made from elastic silicone and glass. Each model was exposed to a pulsating perfusion. The effluent was collected and filtered. For the bifurcational aneurysms, commercially available occlusion balloon catheters with a working channel exiting at the tip were used. For the aneurysms with straight parent vessel, the catheters were modified so that the balloon opened eccentrically. The working channel of the catheter led to a side hole, which was located where the balloon membrane was fixed to the catheter shaft. The aneurysms were filled with coils, ethibloc, or hydrogel, and with coils combined with ethibloc or hydrogel, while the expanded balloon occluded the neck. RESULTS: Embolization of aneurysms under balloon occlusion of the neck was technically feasible with the catheter devices. Dense packing with coils was possible in all cases without coil dislocation, but unfilled interspaces remained between the coil wires. Best filling was achieved with ethibloc or hydrogel alone or in combination with coils. During the filling procedure, there was no distal embolization of the liquid agents. However, after balloon deflation, considerable amounts of hydrogel or ethibloc were washed out from the aneurysm. CONCLUSIONS: The results suggest that balloon occlusion of the neck allows compact filling and minimizes the risk of dislocation in coil embolotherapy of aneurysms. In nonbifurcational aneurysms, the eccentric balloon catheter seems to be suitable for this treatment concept. Although liquid agents may be safely delivered into the aneurysm under balloon protection, their considerable washout rate after balloon removal requires further refinements of the technique before clinical application is advisable.     

Interventional neuroradiology

Silicone balloons have recently been engineered for endovascular treatment of direct carotid cavernous fistulas. Complete closure of the fistula and preservation of the parent vessel are usually possible. Successful embolization of dural arteriovenous malformations is possible using either an arterial or venous approach. In cerebral arteriovenous malformations, new catheters developed include the Tracker catheter (Target Terapeutics, San Jose, CA). New substances are being investigated for use in embolization. Advances in physiologic monitoring include pressure monitoring with microcatheters, and the usefulness of sodium amobarbital has been confirmed for this purpose. Preoperative embolization often facilitates surgical removal of cerebral arteriovenous malformations. For intracranial aneurysms, endovascular treatment is appropriate when surgery is contraindicated. Reported rates of success for occluding the aneurysm range from 77.4% to 91%, and mortality rates range from 1.7% to 17.9%. Alternatives may include the use of thrombogenic coils. MR imaging and angiography are useful in evaluating thrombus formation and structure. A new nondetachable silicone balloon catheter system has been used successfully for intraluminal angioplasty of vasospastic vessels.     

Balloon-assisted coil embolization of wide-necked aneurysms of the internal carotid artery: medium-term angiographic and clinical follow-up in 22 patients

BACKGROUND AND PURPOSE: The management of broad-necked cerebral aneurysms by Guglielmi detachable coils (GDCs) is technically challenging owing to a variety of factors, including difficulty in defining the aneurysm/parent vessel interface angiographically and problems in achieving complete occlusion, later predisposing the aneurysm to regrowth/recanalization. We sought to determine whether the use of intraluminal balloons to remodel the parent vessel/aneurysm interface during GDC embolization would provide a safe means of improving the efficacy of endovascular treatment of broad-necked aneurysms. METHODS: Twenty-two saccular aneurysms of the internal carotid artery were treated with GDCs by using balloon remodeling techniques. All aneurysms were characterized by wide necks or were small with unfavorable neck/fundus ratios and required balloon assistance for coil embolization. Patients were followed up both clinically and angiographically. RESULTS: By using a microcatheter-mounted nondetachable balloon to provide a temporary barrier across the aneurysmal neck, we were able to deploy GDCs safely within a variety of aneurysms. Among the 22 patients treated, aneurysmal occlusion on follow-up angiography (mean, 19 months) was found in 17 of 20 patients (two patients died and no follow-up studies were available). Observed or suspected thromboembolic events occurred in four of 22 patients, resulting in one permanent deficit. Twenty of the 22 patients had good to excellent clinical outcomes. CONCLUSION: Although balloon-assisted coiling of cerebral aneurysms requires manipulation of a second microcatheter and an inflatable balloon, increasing its technical complexity, we believe that this method has utility in treating broad-necked aneurysms and small aneurysms that are otherwise suboptimally managed by conventional GDC deployment.     

Multiple Coaxial Catheter System for Reliable Access in Interventional Stroke Therapy

In some patients with acute cerebral vessel occlusion, navigating mechanical thrombectomy systems is difficult due to tortuous anatomy of the aortic arch, carotid arteries, or vertebral arteries. Our purpose was to describe a multiple coaxial catheter system used for mechanical revascularization that helps navigation and manipulations in tortuous vessels. A triple or quadruple coaxial catheter system was built in 28 consecutive cases presenting with acute ischemic stroke. All cases were treated by mechanical thrombectomy with the Penumbra System. In cases of unsuccessful thrombo-aspiration, additional thrombolysis or angioplasty with stent placement was used for improving recanalization. The catheter system consisted of an outermost 8-Fr and an intermediate 6-Fr guiding catheter, containing the inner Penumbra reperfusion catheters. The largest, 4.1-Fr, reperfusion catheter was navigated over a Prowler Select Plus microcatheter. The catheter system provided access to reach the cerebral lesions and provided stability for the mechanically demanding manipulations of thromboaspiration and stent navigation in all cases. Apart from their mechanical role, the specific parts of the system could also provide access to different types of interventions, like carotid stenting through the 8-Fr guiding catheter and intracranial stenting and thrombolysis through the Prowler Select Plus microcatheter. In this series, there were no complications related to the catheter system. In conclusion, building up a triple or quadruple coaxial system proved to be safe and efficient in our experience for the mechanical thrombectomy treatment of acute ischemic stroke.