Mechanical detachable platinum coil: report of the European phase II clinical trial in 60 patients

PURPOSE: To determine the safety and reliability of the mechanical detachment system of a platinum coil (Detach-18) when used for neurovascular embolization. MATERIALS AND METHODS: Sixty patients (21 men, 39 women; age range, 26-75 years; mean age, 56.2 years) were treated in seven centers. Ease of introduction of the coil to the microcatheter, effect of coil passage on the microcatheter shape and stability during its delivery, retrievability of the coil before and after the transition zone passed beyond the microcatheter, detachment of the coil, and effect of coil rotation on the microcatheter stability were evaluated. The detachment system itself was evaluated for premature detachment, failure of the coil to detach, detachment time, number of turns, visibility of radiopaque markers, number of coils deployed per patient, and percentage of vessel occlusion obtained. A 0.015-inch-diameter regular coil and a 0.014-inch-diameter soft coil were used. RESULTS: A total of 1,061 coils were used; 1,009 were detached. The number of coils deployed ranged from four to 104 (mean, 17 coils). The coils passed easily through the microcatheter. The detachment maneuver occurred within 5-25 seconds, with five to 60 turns of the introducing wire. One premature coil detachment occurred without clinical sequela; 100% occlusion of the vessel lumen was achieved in 53 patients; 80%-90%, in four; and 70%-80%, in two. There were no device-related complications. CONCLUSION: The detachment system was safe and reliable. This is a useful system for coil embolization in neurovascular diseases.     

双微导管技术在宽颈颅内动脉瘤栓塞中的初步应用经验

目的　评估采用双微导管技术在宽颈颅内动脉瘤栓塞中的初步经验。方法　 6例宽颈动脉瘤在常规方法应用无效后采用双侧股动脉入路 ,把 2支微导管置入动脉瘤腔内 ,由微导管内同时或先后送入弹簧圈 ,待弹簧圈稳定后解脱 ,随后再送入更多的弹簧圈以达到致密填塞。结果　 6例AN成功地栓塞 ,10 0 %闭塞 2个、闭塞 >90 %的 4个。缺血性并发症 1例 ,导致中残。术后 3月时GOS优良 5例、中残 1例。有 5例进行了造影随访 ,无AN复发和再破裂。结论　双微导管技术对于某些复杂的宽颈动脉瘤是一种可供选择的方法。     

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.     

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.     

Low-angled microcatheter approach for coil embolization of the anterior choroidal artery aneurysm

Purpose

Thromboembolic complication is a serious concern following coil embolization for aneurysms involving the anterior choroidal artery (AChA). To minimize this complication and to improve packing density, we present a technical concept of coil embolization.

Methods

We attempted packing of the aneurysmal sac by lowering the microcatheter approach angle into an aneurysm to secure AChA origin as well as to improve coil packing density of the aneurysm. This technical concept involves approaching the aneurysm sac with an adjusted shaping of the microcatheter tip to achieve the effect which was not obtained when the microcatheter approach angle into the aneurysm sac was high (≥90°). We evaluated immediate angiographic outcome by the Raymond classification, coil packing density, and follow-up results (modified Rankin Scale (mRS) and recurrence) in seven aneurysms involving AChA in six patients.

Results

We achieved immediate angiographic outcome of the Raymond classes I or II with 31% mean packing density. The AChA origin was preserved without any procedure-related complication. There was neither clinical event (mRS = 0) nor aneurysm recurrence confirmed on the source image of magnetic resonance angiography during 6–9 months follow-up.

Conclusions

The technical concept of low-angled microcatheter approach can be useful to improve coil packing density and to secure AChA origin when AChA arises near the aneurysm.

     

Retrograde stenting through the posterior cerebral artery in coil embolization of the posterior communicating artery aneurysm

Introduction

Protection techniques using stents or balloons are occasionally limited in coil embolization of wide-necked posterior communicating artery (PcomA) aneurysms in which the PcomA originated from the aneurysm neck at an acute angle. Here, we present two cases undergoing retrograde stenting through the posterior cerebral artery in coil embolization of the PcomA aneurysms.

Methods

To perform retrograde stenting, a microcatheter used for stent delivery was advanced from the vertebral artery (VA) to the terminal internal carotid artery (ICA) via the ipsilateral P1 and the PcomA. The aneurysm sac was selected with another microcatheter for coil delivery through the ipsilateral ICA. Coil embolization was performed under the protection of a stent placed from the terminal ICA to the PcomA.

Results

Deployment of the stent was successful in both aneurysms treated using retrograde stenting by the VA approach. Coil deployment was performed through the jailed microcatheter at first. The microcatheter was repositioned through the stent struts later in one case and another microcatheter was inserted into the sac through the stent struts in the other case. Both aneurysms were occluded properly with the coils without procedure-related complications.

Conclusion

By providing complete neck coverage, retrograde stenting for coil embolization in wide-necked PcomA aneurysms seems to be a good alternative treatment strategy, when the aneurysms are incorporating extended parts of the PcomA, and the PcomA and P1 are big enough to allow passage of the microcatheter for delivery of the stent. However, this technique should be reserved for those cases with the specific vascular anatomy.     

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.     

Marker alignment for Guglielmi detachable coil embolization: practical considerations

BACKGROUND AND PURPOSE: Aneurysm embolization is not without risk: numerous technical aspects are considered before, during, and after the procedure. The purpose of this study was to show the position of the detachment zone of a Guglielmi detachable coil (GDC) with respect to the catheter tip for various microcatheters and marker alignments. METHODS: Six types of commonly used microcatheters were tested (Excel-14, Excelsior, FasTracker-10, Prowler-10, Prowler-14, and Rebar-14). First, the catheter markers and the distance from the catheter tip to the distal end of the proximal and distal markers of each catheter were compared. Second, the coil maker was aligned with the catheter marker. Third, the distal 3 cm of the microcatheter was modified by random shaping, with or without steaming. Last, marker alignment was tested with resterilized microcatheters (ethylene oxide gas sterilization). RESULTS: The length of the catheter marker and the distance between the catheter tip and the distal end of the proximal and distal catheter markers varied among the microcatheters. Sometimes, they varied even within the same microcatheter type. When a GDC was advanced until the proximal end of the marker on the delivery wire was exactly distal to the proximal catheter marker, the coil detachment zone was positioned at approximately 1.0 to 1.5 mm outside the catheter tip. Steaming or shaping of the distal 3 cm of the microcatheters resulted in the GDCs protruding more from the catheter tip. Resterilization also had an effect of marker distance shortening. Microcatheters were easily stretched by usual handling, such as removing a shaping mandrel from the catheter tip. CONCLUSION: Our study shows that proper marker alignment is influenced by many factors, including microcatheter type, steaming, shaping, sterilization, and manual handling.     

Stent-assisted coil embolization of wide-necked renal artery bifurcation aneurysms

PURPOSE: To report preliminary results of stent-assisted coil embolization in the treatment of wide-necked renal artery bifurcation aneurysms. MATERIALS AND METHODS: Four patients (three women, one man; mean age, 54 years; range, 49-67 y) with wide-necked renal artery aneurysms were treated with dedicated neurointerventional self-expanding nitinol stent-assisted coil embolization during a 2-year period. The stent was delivered over the neck of the aneurysm, after which the aneurysm was filled with detachable coils through a microcatheter placed into the aneurysm through the stent mesh. RESULTS: Stent delivery and coil embolization was successfully completed in all cases. Complete aneurysm occlusion without coil protrusion or arterial flow compromise was obtained in all patients. A small peripheral subsegmental renal infarction necessitating no therapy was registered in one patient on postembolization computed tomography. At follow-up angiography 1 year after embolization, no aneurysm recanalization or arterial obstruction was registered. CONCLUSIONS: Our preliminary experience indicates that stent-assisted coil embolization is technically feasible and effective for the exclusion of challenging renal artery bifurcation aneurysms without the sacrifice of any branch arteries.     

可脱微弹簧圈栓塞术治疗颅内动脉瘤

目的 探讨颅内动脉瘤可脱微弹簧圈栓塞治疗术的效果。方法 经股动脉Seldinger穿刺法,将导引管送至C2以上,将微导管置于动脉瘤腔,结合不同的方式,进行可脱微弹簧圈栓塞动脉瘤。结果 36例用GDC,6例Metrix,18例DCS,2例ORBIT,3例EDC,4例配合支架栓塞;65例患者,59例康复,3例后遗偏瘫,1例自动出院,5例死亡。59例随访,头颅平片GDC均在瘤腔,无再出血,5例患者复查DSA,无复发。结论 微弹簧圈栓塞是治疗颅内动脉瘤微创有效安全的方法。     

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.     

Multiple cerebral aneurysms associated with Takayasu arteritis successfully treated with coil embolization

The cerebrovascular complications of Takayasu arteritis are primarily related to the presence of occlusive lesions. Cerebral aneurysms rarely occur as complications; only 18 cases have been reported thus far. The use of coil embolization to treat cerebral aneurysms occurring as a complication of Takayasu arteritis has not been previously reported. We report a case of Takayasu arteritis with a basilar tip aneurysm and a P1 segment aneurysm of the left posterior cerebral artery that were successfully treated with coil embolization. Because coil embolization for cerebral aneurysms associated with Takayasu arteritis requires the use of limited access routes that have extremely curved and tortuous courses, catheter navigation was difficult. The guide catheter, microcatheter, and guidewire must be selected and navigated with greater care than is usually required for common aneurysm embolization.     

GDC血管内栓塞治疗颅内动脉瘤

目的 探讨电解可脱性弹簧圈（GDC）血管内栓塞治疗颅内动脉瘤的疗效和技术要点。方法 对31例动脉瘤患者应用微导管技术,通过数字减影全脑血管造影,采用GDC作动脉瘤囊内填塞治疗。结果 31例31枚动脉瘤中28枚瘤腔完全闭塞,3枚95％闭塞。术后30例临床痊愈;1例死亡;病死率3．2％。术中并发动脉瘤再破裂出血1例;术后弹簧圈末端逸出1例。术后随访0．5～3年均无再出血。结论 GDC血管内栓塞治疗颅内动脉瘤疗效可靠,早期栓塞及有效的术后处理是提高治愈率的重要方法。     

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 report of the clinical use of the detach-18 mechanical detachable platinum coil in 41 patients

BACKGROUND AND PURPOSE: The purpose of this study was to determine the safety and reliability of the mechanical detachment system of a new platinum coil, Detach-18, when used as a vascular occlusive device for neurovascular disease. METHODS: Forty-one patients (nine male and 32 female patients; age range, 26-75 years; mean age, 54.4 years) underwent treatment at seven centers. Twenty-two patients had dural arteriovenous fistulae of the transverse sinus treated by a transvenous route. Fourteen patients underwent internal carotid artery occlusion in the treatment of aneurysms, meningioma, facial tumor, or carotid injury. One patient underwent occlusion of the basilar artery and one patient underwent occlusion of the vertebral artery for treatment of aneurysms. In two patients, coils were used as part of the treatment of their arteriovenous malformations. In all cases, the Detach-18 coils were delivered through a microcatheter with two distal markers. Two types of coils, a 0.015-inch-diameter "regular" coil and a 0.014-inch-diameter "soft" coil, were used. RESULTS: A total of 569 coils were used, 541 of which were detached. The number of coils in ranged from four to 53 (average number of coils, 14). The coils passed easily through the microcatheter. The detachment maneuver occurred within 10 to 25 s with 20 turns of the introducing wire. No premature coil detachment occurred. Complete occlusion of the vessel lumen was achieved in 35 cases. In three cases, 80% to 90% occlusion was achieved. In two cases, 70% to 80% occlusion was achieved. There were no device-related complications. CONCLUSION: The detachment system was safe, reliable, consistent, and fast. This is a useful system for coil embolization in neurovascular applications.     

Endovascular coil embolization of middle cerebral artery aneurysms of the proximal (M1) segment

Introduction

Proximal middle cerebral artery (M1 segment) aneurysms have various configurations and are distinct from middle cerebral artery bifurcation aneurysms. We present the clinical and radiological results of coil embolization of the M1 segment aneurysms.

Methods

From a prospective database, we retrieved the data for 59 consecutive patients harboring 60 M1 aneurysms that were treated with endovascular coil embolization from January 2006 to May 2012. We assessed the clinical outcomes of the patients and morphological outcomes of the aneurysms using the Raymond classification.

Results

The aneurysms were located on the superior wall of the M1 segment in 43 and on the inferior wall in 17. Superior-wall aneurysms were related to the frontal cortical artery and the lateral lenticulostriate perforator while inferior-wall aneurysms were to the temporal cortical artery. With coil embolization, complete aneurysmal occlusion or residual neck could be achieved in 52 aneurysms (86.7 %) and residual aneurysm in 8. The microcatheter protection technique was most commonly used for coil embolization (41.7 %) followed by single microcatheter (31.7 %), double microcatheter (23.3 %), and stent protection (3.3 %). There was no procedure-related morbidity or mortality. Follow-up angiography more than 6 months after embolization (n?=?46; mean 12.4 months) demonstrated stable occlusion in 40 (87.0 %), minor recanalization in 4 (8.7 %), and major recanalization in 2 (4.3 %). One patient experienced delayed cerebral infarction without permanent neurologic deficit.

Conclusion

Coil embolization in M1 aneurysms seems to be safe and efficacious, although it may require various technical strategies due to distinct anatomic configurations.     

Stent-assisted coil embolization of intracranial wide-necked aneurysms

The endovascular treatment of cerebral aneurysms with coils poses significant technical challenges, particularly with respect to wide-necked aneurysms. We present the results of our initial experiences in using a stent for endovascular treatment of aneurysms, with an emphasis on potential applications, technical aspects, and associated complications. Twenty-three wide-necked aneurysms from 22 patients were treated during the 13-month study period. Seven patients presented with subarachnoid hemorrhage. Aneurysms were located at the internal carotid artery (n=14), the vertebral artery (n=3), the basilar artery (n=5), and the middle cerebral artery (n=1). A Neuroform stent² was used for stent-assisted procedures. Premedication with antithrombotic agents was available for unruptured cases. Postprocedural antithrombotic medication was prescribed for all patients. Nineteen aneurysms were primarily stented, followed by coil placement. For five of these aneurysms, stenting was performed subsequent to failure of an attempt to frame with an initial coil. Stenting for the remaining four aneurysms was performed as a rescue procedure to prevent the migration of previously placed coils. Complete occlusion was obtained in ten aneurysms, nearly complete occlusion (95% or more occluded) in 11 aneurysms, and partial occlusion (less than 95% occluded) in one aneurysm. In one aneurysm, we failed to navigate the microcatheter into the aneurysmal sac through the interstices of the stent. Stent thrombosis was noted during the procedure in one patient. Hemorrhagic complication on the 25th day after the procedure was noted in one patient. No procedure-related complications were observed during the procedure or during follow-up in the remaining 20 patients, including seven patients who did not receive antithrombotic agents prior to endovascular treatment owing to recent subarachnoid hemorrhage. To overcome the technical limitation in the coiling of wide-necked aneurysms, stent-assisted coil embolization may be a technically feasible and relatively safe method, even though longer periods of follow-up are required.     

Microcatheter Looping to Facilitate Aneurysm Selection in Coil Embolization of Paraclinoid Aneurysms

ObjectiveDescribed herein is a microcatheter looping technique to facilitate aneurysm selection in paraclinoid aneurysms, which remains to be technically challenging due to the inherent complexity of regional anatomy.ResultsThrough this looping technique, a total of 59 paraclinoid aneurysms were successfully treated. After aneurysm selection as described, single microcatheter technique (n = 25) was most commonly used to facilitate coiling, followed by balloon protection (n = 21), stent protection (n = 7), multiple microcatheters (n = 3), and stent/balloon combination (n = 3). Satisfactory aneurysmal occlusion was achieved through coil embolization in 44 lesions (74.6%). During follow-up of 53 patients (mean interval, 10.9 ± 5.9 months), only one instance (1.9%) of major recanalization was observed. There were no complications related to microcatheter looping.ConclusionThis microcatheter looping method facilitates safe and effective positioning of microcatheter into domes of paraclinoid aneurysms during coil embolization when other traditional microcatheter selection methods otherwise fail.     

Catheter-aided extraction of a steel coil accidentally lodged in the right ventricle

In one case a steel coil similar to the Gianturco coil accidentally lodged in the outflow tract of the right ventricle during the embolization of a pulmonary arteriovenous fistula. Extraction of the coil with an intravascular foreign body retrieval set (Cook Inc., Bloomington Ind.) was unsuccessful because the extraction wire broke. An improvised device was then employed, using a Cordis 8 French multipurpose catheter and a single stainless steel wire designed for surgical osteosynthesis. The steel coil was successfully caught by the device and pulled out via the femoral vein.     

Neurovascular embolization: in vitro evaluation of a mechanical detachable platinum coil system

The authors evaluated a mechanically detachable platinum coil system intended for neurovascular use. The introduction characteristics, ease of delivery, ease of retrieval, and detachability were studied with fluoroscopic guidance with in vitro silicone models. All the coils passed easily through the microcatheter. The detachment maneuver occurred within 20 seconds with 20 or fewer rotations of the pusher wire. One of 229 coils detached prematurely but only after deliberate and extreme manipulation. The detachment system is safe, reliable, and consistent and will be useful for interventional neuroradiologists.