Coil embolization in precommunicating (A1) segment aneurysms of anterior cerebral artery

Introduction

Precommunicating (A1) segment aneurysms of the anterior cerebral artery are rare and often pose technical challenges for coil embolization due to their distinctive configurations. Clinical and radiologic outcomes of treating such aneurysms through endovascular coil embolization are presented herein.

Methods

Data accruing prospectively from May 2002 to August 2013 yielded 48 patients harboring 50 A1 segment aneurysms, each classified as proximal, middle, or distal by location. Clinical outcome of the patients and morphological outcome of the aneurysms were assessed, with emphasis on technical aspects of treatment.

Results

The aneurysms studied occupied either proximal (n?=?39), middle (n?=?6), or distal (n?=?5). Proximal aneurysms were largely directed posteriorly (80 %), and most (97 %) were devoid of branches. Middle and distal aneurysms were associated with the medial lenticulostriate artery, cortical branches, or fenestrations. The preshaped “S” and steam-shaped “S” microcatheters facilitated aneurysm selection in 60 % of lesions. Single-microcatheter technique was most commonly applied for coil embolization (62 %), followed by balloon protection (16 %). Successful aneurysmal occlusion could be achieved in 76 % of the patients, with no procedure-related morbidity and mortality. At final follow-up (mean interval, 29.9 months), stable aneurysmal occlusion was sustained in 93 % of the patients (40/43).

Conclusion

A1 segment aneurysms are amenable to safe and efficacious endovascular coil embolization by adjusting procedural strategy to accommodate distinctive anatomic configurations.     

Coil embolization of anterior circulation aneurysms supported by the Solitaire™ AB Neurovascular Remodeling Device

Introduction

The purpose of the study is to evaluate patients with wide-necked or complex aneurysms of the anterior circulation who underwent Solitaire? AB Neurovascular Remodeling Device-assisted coil embolization.

Methods

From February 2008 to March 2009, consecutive data were collected from 45 patients with anterior circulation aneurysms. Eighteen of the patients presented with acute subarachnoid hemorrhage. Forty-six aneurysms were treated with the aid of different applications (n?=?49) of the Solitaire? AB Remodeling Device followed by standard coiling procedure (n?=?43) using bioactive coils or/and bare coils.

Results

Successful positioning of the remodeling device was obtained in 95.9% of the cases. There were two thromboembolic complications (4.1%) and one severe vasospasm requiring retrieval of the device. Permanent procedural morbidity was observed in one patient (2%). The proportion of patients in whom Raymond class 1 occlusion was obtained was 53.5% (n?=?23). Raymond class 2 occlusion was achieved in 42% (n?=?18) and Raymond class 3 occlusion in 4.7% (n?=?2). Thirty-nine patients left the hospital with a good clinical status.

Conclusion

The initial technical and clinical results of Solitaire? AB device-assisted coiling of aneurysms in the anterior circulation are highly encouraging. This technique may enhance the possibilities of the endovascular treatment of these aneurysms in clinical routine.     

Endovascular Broad-Neck Aneurysm Creation in a Porcine Model Using a Vascular Plug

Purpose

Ruptured cerebral arterial aneurysms require prompt treatment by either surgical clipping or endovascular coiling. Training for these sophisticated endovascular procedures is essential and ideally performed in animals before their use in humans. Simulators and established animal models have shown drawbacks with respect to degree of reality, size of the animal model and aneurysm, or time and effort needed for aneurysm creation. We therefore aimed to establish a realistic and readily available aneurysm model.

Materials and Methods

Five anticoagulated domestic pigs underwent endovascular intervention through right femoral access. A total of 12 broad-neck aneurysms were created in the carotid, subclavian, and renal arteries using the Amplatzer vascular plug.

Results

With dedicated vessel selection, cubic, tubular, and side-branch aneurysms could be created. Three of the 12 implanted occluders, two of them implanted over a side branch of the main vessel, did not induce complete vessel occlusion. However, all aneurysms remained free of intraluminal thrombus formation and were available for embolization training during a surveillance period of 6 h. Two aneurysms underwent successful exemplary treatment: one was stent-assisted, and one was performed with conventional endovascular coil embolization.

Conclusion

The new porcine aneurysm model proved to be a straightforward approach that offers a wide range of training and scientific applications that might help further improve endovascular coil embolization therapy in patients with cerebral aneurysms.     

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.     

Woven Endobridge (WEB) Device for endovascular treatment of ruptured intracranial wide-neck aneurysms: a single-center experience

Introduction

Endovascular treatment of ruptured wide-neck bifurcation aneurysms presents a challenge. While still under evaluation, the Woven Endobridge (WEB) aneurysm embolization system has so far shown promising results in the treatment of complex bifurcation aneurysms. We aimed to evaluate the feasibility and short-term follow-up of endovascular treatment of ruptured wide-neck aneurysm with the WEB device.

Methods

Six patients referred to our institution for acute symptomatic subarachnoid hemorrhage (SAH) and treated with the WEB device were enrolled in this study. Clinical presentations, technical details, intraoperative and postoperative complications, and outcomes were recorded. Immediate and 3-month angiographic results were also evaluated.

Results

Three middle cerebral artery (MCA) and three anterior communicating artery aneurysms were treated between 1 and 14 days after rupturing. Average dome width was 5.8 mm (range 5–7), average neck size was 4.5 mm (range 4–5), and average dome-to-neck ratio was 1.3 (range 1–1.7). The WEB system was the exclusive treatment and was successfully deployed in all cases. Per procedural thromboembolic events occurred in two cases and were treated with intra-arterial administration of antiplatelet agents without any clinical consequences. The modified Rankin Scale (mRS) score at discharge was 0 for all patients. The 3-month angiographic follow-up showed adequate occlusion in four of our six patients (67 %).

Conclusion

From this preliminary study, the high feasibility rate and lack of need for systematic antiplatelet agents favor the WEB device providing a solution for endovascular treatment of ruptured wide-neck bifurcation aneurysms during the acute phase. However, further studies are needed to evaluate the complication rate and long-term efficiency.     

Factors predicting retreatment and residual aneurysms at 1?year after endovascular coiling for ruptured cerebral aneurysms: Prospective Registry of Subarachnoid Aneurysms Treatment (PRESAT) in Japan

Introduction

Endovascular treatment of cerebral aneurysms includes follow-up imaging to identify aneurysms that may need retreatment. The aim of this study was to determine predictors of incomplete aneurysm occlusion at 1?year after endovascular coiling for ruptured cerebral aneurysms.

Methods

In 129 patients of the Prospective Registry of Subarachnoid Aneurysms Treatment cohort, ruptured aneurysms were coiled within 14?days of onset and both initial post-coiling and 1-year follow-up digital subtraction angiography or magnetic resonance angiography were obtained. Factors predicting 1-year incomplete aneurysm occlusion (retreatment within 1-year or residual aneurysms at 1?year) were determined using multivariate logistic regression analyses.

Results

One-year incomplete aneurysm occlusion was identified in 59 patients, including ten patients who were retreated within 1-year post-coiling. Dome size ≥7.5?mm (P?=?0.007, odds ratio (OR)?=?5.00, 95% confidence interval (CI)?=?1.55–16.15), pre-treatment aneurysm re-rupture (P?=?0.023, OR?=?3.50, 95% CI?=?1.19–10.31), non-small size/small neck aneurysm (dome size, ≥10?mm or neck size, ≥4?mm; P?=?0.022, OR?=?3.26, 95% CI?=?1.19–8.96), and residual aneurysms on immediate post-coiling angiograms (P?=?0.017, OR?=?1.43, 95% CI?=?1.07–1.93) significantly predicted incomplete aneurysm occlusion at 1-year post-coiling.

Conclusions

In addition to the characteristics of aneurysm and initially incomplete aneurysm occlusion, this study showed pre-treatment aneurysm re-rupture to be a predictor that favors closer imaging follow-ups for coiled aneurysms.     

Balloon-assisted coil embolization of the celiac trunk before endovascular aortic repair of thoracoabdominal aortic aneurysm

Purpose

Celiac trunk coil embolization before thoracic endovascular aneurysm repair (TEVAR) of a thoracoabdominal aortic aneurysm involving the celiac trunk can prevent type II endoleaks. One disadvantage of conventional coil embolization is the risk of coil displacement. We performed coil embolization under balloon occlusion of the celiac trunk to address this issue.

Materials and methods

Between December 2008 and January 2011, 5 patients (3 men and 2 women, mean age 76 years) were included in this study. For all patients, after confirming the collateral blood flow from the superior mesenteric artery via the pancreaticoduodenal arcades by using the balloon occlusion test, celiac trunk coil embolization proceeded under balloon occlusion of the proximal part of the celiac trunk.

Results

Balloon-assisted coil embolization of the celiac trunk was completed for all patients without any complications. All coils were deployed as planned in the short segment of the celiac trunk without displacement. Coil migration, ischemic complications, and endoleaks via the celiac trunk did not arise in any of the patients over a follow-up period of 77–637 (mean 258) days.

Conclusions

Balloon-assisted coil embolization of the celiac trunk before TEVAR could be a feasible treatment option for suitable patients.     

Modified protection using far proximal portion of self-expandable closed-cell stents for embolization of wide-necked intracranial aneurysms

Introduction

Stent-assisted embolization is sometimes limited in wide-necked aneurysms involving the acute-angled origins of tortuous branching arteries, and occasionally, Y-shaped stenting is required to remedy the sweeping effects of a broad aneurysmal neck on arterial branches. Described herein is a modified stent-assisted coil embolization technique entailing strategic placement of far proximal stent (“distal stenting”) as an alternate approach in such scenarios.

Methods

For this particular technique, stent placement is confined to a branch artery, allowing far proximal stent to cover aneurysmal neck, with no bridge to parent artery. Kinking of stents deployed in tortuous arteries is thereby avoided, and better coverage of aneurysmal neck is achieved, compared with traditional stent protection. Records of 12 consecutive patients with wide-necked aneurysms, all treated by coil embolization with distal stenting between January 2009 and February 2014, were retrieved from a prospective data repository at our institution. Outcomes were analyzed in terms of morphologic features and clinical status.

Results

This modified technique was largely applied to aneurysms of middle cerebral artery, followed by posterior communicating artery and anterior communicating artery sites. With one exception, all aneurysms treated were successfully occluded. There were no complications directly related to distal stenting. At final follow-up (mean interval, 16.8?±?9.7 months), complete aneurysmal occlusion was sustained in 81.8 %. Delayed stent migration was observed in one patient (8.3 %).

Conclusion

Our study suggests that distal stenting in wide-necked aneurysms is a reasonable alternative to traditional stent protection, despite the potential for delayed stent migration.     

Early and midterm results of complex cerebral aneurysms treated with Silk stent

Introduction

Endovascular treatment of intracranial aneurysms has been an effective treatment option. In this paper, we report our experience with the Silk stent (SS) for endovascular treatment of complex intracranial aneurysms and present periprocedural events, immediate results, delayed complications, and imaging and clinical follow-up results.

Methods

We retrospectively examined angiographic images and clinical reports of 76 consecutive patients with 87 intracranial aneurysms who were treated with SSs between March 2008 and June 2011.

Results

All aneurysms could be successfully covered technically using implanted SSs, with an overall mortality of 6.6?%. Two transient morbidities (2.6?%) and three permanent morbidities due to embolic events (3.9?%) were observed. Unexpected procedural technical events occurred in 18 procedures (18/78, 23.1?%). Control angiographies were performed in all 71 patients with 82 aneurysms (100?%). Mean angiographic follow-up time was 17.5?±?11.1?months [range 2?C48?months]. Sixteen of the 71 patients with 19 aneurysms had only early angiographic controls in the first 6?months while remaining 55 patients with 63 aneurysms (77.5?%) had late controls after 6?months. Overall control angiographic occlusion rates were as follows: 87.8?% (72/82) total occlusion, 8.5?% residual aneurysm filling, and 3.7?% residual neck filling. The general in-stent stenosis rate in controls was 5.6?% and the stented parent artery occlusion rate was 4.2?%. Five (6.6?%) aneurysms ruptured after stent implantation in our series.

Conclusion

The Silk stent is an effective tool for the treatment of challenging aneurysms, which have previously demonstrated higher re-growth rates and technical problems, despite unexpected higher hemorrhage rates after treatment and deployment difficulties.     

Endovascular management for retreatment of postsurgical intracranial aneurysms

Introduction

Incomplete surgical treatment of intracranial aneurysms and recurrent postsurgical aneurysms are associated with a risk of rebleeding, and additional treatment is generally recommended. Surgical retreatment may carry a risk of procedural complications due to technical difficulty. We present here our experience with the endovascular approach for the retreatment of intracranial aneurysms that were initially treated with open surgery.

Methods

From January 2002 through January 2013, a total of 43 patients with 43 postsurgical index aneurysms were identified and underwent subsequent endovascular treatment. Clinical and radiological data were retrospectively reviewed.

Results

Thirty-one patients were surgically clipped before endovascular coiling and 12 patients were nonclipped, which included wrapping. Hemorrhagic presentation occurred in 21 patients prior to coiling. The interval between the initial surgical treatment and coiling varied from 0 days to 264 months (median, 9 months). Endovascular coiling resulted in the successful occlusion of 36 aneurysms (84 %). Procedure-related complications included asymptomatic thrombus formation in six patients, symptomatic cerebral infarction in two patients, and retroperitoneal hemorrhage in one patient. Delayed cerebral infarction occurred in two patients with a deployed stent. The procedure-related permanent morbidity and mortality rates were 6.9 and 0 %, respectively. Radiological follow-up evaluations beyond 6 months were available in 26 patients (60 %), which revealed major recanalization in three patients (11.5 %). There was no rebleeding during the follow-up period, which ranged from 3 to 115 months (mean, 34.5 months).

Conclusion

Endovascular embolization may serve as a safe, efficacious, and durable treatment option in the management of postsurgical intracranial aneurysms.     

Endovascular Coil Embolization of Very Small Intracranial Aneurysms

Objective

We aimed to evaluate the results of endovascular coil embolization for very small aneurysms (≤ 3 mm).

Materials and Methods

Between March 2005 and December 2008, a total of 31 very small aneurysms in 30 patients were treated by coil embolization. Of the 31 aneurysms, five (16%) were ruptured, as opposed to 26 (84%) that were not. We assessed the procedural complications, immediate angiographic outcome after coiling, clinical outcome, and follow-up MR angiography (MRA).

Results

Two thromboembolic complications occurred during the procedure, but did not lead to any persistent neurologic deficit. No procedural aneurysmal rupture was observed and procedure-related morbidity and mortality were both 0%. Occlusion was adequate in 25 aneurysms (81%) and incomplete in six aneurysms (19%). The clinical outcomes of five patients with ruptured aneurysms were good (Glasgow outcome scale ≥ 4), with no bleeding of the treated aneurysms during a mean follow-up period of 13.3 months. On 27 follow-up MRA, there was no recurrence, and the five incompletely occluded aneurysms showed a spontaneous amelioration resulting in an adequate occlusion.

Conclusion

Coil embolization of very small aneurysms is technically feasible with good results. The long-term efficacy and the potential as a standard treatment strategy remain to be determined by randomized large trials.     

Coil embolization of intracranial saccular aneurysms using the Low-profile Visualized Intraluminal Support (LVIS™) device

Introduction

The novel Low-profile Visualized Intraluminal Support (LVIS?, LVIS and LVIS Jr.) device was recently introduced for stent-supported coil embolization of intracranial aneurysms. Periprocedural and midterm follow-up results for its use in stent-supported coil embolization of unruptured aneurysms are presented herein.

Methods

In this prospective multicenter study, clinical and radiologic outcomes were analyzed for 55 patients with saccular aneurysms undergoing LVIS-assisted coil embolization between October 2012 and February 2013. Magnetic resonance angiography or digital subtraction angiography was performed to evaluate midterm follow-up results.

Results

The standard LVIS device, deployed in 27 patients, was more often used in internal carotid artery (ICA) aneurysms (n?=?19), whereas the LVIS Jr. (a lower profile stent, n?=?28) was generally reserved for anterior communicating artery (n?=?14) and middle cerebral artery (n?=?8) aneurysms. With LVIS-assisted coil embolization, successful occlusion was achieved in 45 aneurysms (81.8 %). Although no instances of navigation failure or stent malposition occurred, segmentally incomplete stent expansion was seen in five patients where the higher profile LVIS was applied to ICA including carotid siphon. Procedural morbidity was low (2/55, 3.6 %), limited to symptomatic thromboembolism. In the imaging of lesions (54/55, 98.2 %) at 6-month follow-up, only a single instances of major recanalization (1.9 %) occurred. Follow-up angiography of 30 aneurysms (54.5 %) demonstrated in-stent stenosis in 26 (86.7 %), with no instances of stent migration. Only one patient suffered late delayed infarction (modified Rankin Scale 1).

Conclusion

The LVIS device performed acceptably in stent-assisted coil embolization of non-ruptured aneurysms due to easy navigation and precise placement, although segmentally incomplete stent expansion and delayed in-stent stenosis were issues.     

Aneurysmal wall enhancement and perianeurysmal edema after endovascular treatment of unruptured cerebral aneurysms

Introduction

Perianeurysmal edema and aneurysm wall enhancement are previously described phenomenon after coil embolization attributed to inflammatory reaction. We aimed to demonstrate the prevalence and natural course of these phenomena in unruptured aneurysms after endovascular treatment and to identify factors that contributed to their development.

Methods

We performed a retrospective analysis of consecutively treated unruptured aneurysms between January 2000 and December 2011. The presence and evolution of wall enhancement and perianeurysmal edema on MRI after endovascular treatment were analyzed. Variable factors were compared among aneurysms with and without edema.

Results

One hundred thirty-two unruptured aneurysms in 124 patients underwent endovascular treatment. Eighty-five (64.4 %) aneurysms had wall enhancement, and 9 (6.8 %) aneurysms had perianeurysmal brain edema. Wall enhancement tends to persist for years with two patterns identified. Larger aneurysms and brain-embedded aneurysms were significantly associated with wall enhancement. In all edema cases, the aneurysms were embedded within the brain and had wall enhancement. Progressive thickening of wall enhancement was significantly associated with edema. Edema can be symptomatic when in eloquent brain and stabilizes or resolves over the years.

Conclusions

Our study demonstrates the prevalence and some appreciation of the natural history of aneurysmal wall enhancement and perianeurysmal brain edema following endovascular treatment of unruptured aneurysms. Aneurysmal wall enhancement is a common phenomenon while perianeurysmal edema is rare. These phenomena are likely related to the presence of inflammatory reaction near the aneurysmal wall. Both phenomena are usually asymptomatic and self-limited, and prophylactic treatment is not recommended.     

Mechanical Recanalization Using Solitaire AB Device for Severe Thromboembolic Events in Endovascular Treatment of Intracranial Aneurysms

Introduction

Severe thromboembolism with complete occlusion of the proximal arteries during or after coil embolization can cause serious neurologic deficits. The study aimed to assess the effectiveness and safety of Solitaire AB device as a rescue therapy for severe thromboembolic complications in the endovascular treatment of intracranial aneurysms.

Materials and Methods

Between February 2013 and April 2016, 1047 intracranial aneurysms treated with endovascular procedures were retrospectively reviewed in our center. Severe thromboembolisms occurred in ten patients and were treated by Solitaire AB device including clot retriever and permanent stent deployment.

Results

The location of arterial occlusion was distal to the aneurysm rather than the coil/parent artery interface or in-stent area. Four patients had distal thromboembolic events before coil embolization, and six patients had it after coiling. The complete arterial recanalization (TICI 3) was achieved in all patients, and no cerebral hemorrhage was related to the procedure after the rescue therapy. Among these patients with the aforementioned neurovascular procedures, the mean Glasgow Outcome Scale (GOS) score was 4.5 (ranging 3–5) and eight cases had good outcome with a score of GOS 4–5 at discharge, while eight patients presented mRS ≤2 at 3-month follow-up.

Conclusions

These results demonstrate that mechanical recanalization using Solitaire AB device seems to be effective and safe as a rescue therapy for severe thromboembolic events during cerebral aneurysm embolization.

     

The LVIS Jr. microstent to assist coil embolization of wide-neck intracranial aneurysms: clinical study to assess safety and efficacy

Introduction

This study was aimed to assess clinical safety and efficacy of the LVIS Jr. microstent in stent-assisted coil embolization of wide-neck intracranial aneurysms.

Methods

IRB approved single-center interventional clinical study in 22 patients (10 females, 12 males, mean age 55, age range 33–74 years) for the endovascular treatment of wide-neck aneurysms. After obtaining informed consent, patients were included according to the following criteria: aneurysm fundus-to-neck ratio?<?2 or neck diameter?>?4 mm, and a parent vessel diameter of ≤3.5 mm. Primary end point for clinical safety was absence of death, absence of major or minor stroke, and absence of transient ischemic attack. Primary end point for treatment efficacy was complete angiographic occlusion according to the Raymond–Roy Occlusion Classification (RROC) immediately after the procedure and at follow-up after 3 and 6 months on magnetic resonance imaging (MRI).

Results

In 20/22 (91 %) of patients, the primary end point of safety was reached; in the two remaining patients, transient ischemic attack, but no permanent deficit was observed; in 16/22 (73 %), efficient occlusion (RROC1) was reached, and in 6/22 (27 %), a residual neck remained (RROC2). Single [seven with antegrade, two in crossover configuration, and four with “first-balloon-then-stent” (FBTS) technique] or double-stent (eight patients with Y configuration and one patient with X configuration) deployment was technically successful in all cases.

Conclusion

Deployment of the LVIS Jr. microstent in various single- or double-stent configurations is safe and effective to assist the treatment of intracranial wide-neck aneurysms.     

Stent-assisted coil embolization of wide-necked posterior inferior cerebellar artery aneurysms

Introduction

Endovascular coil embolization of posterior circulation aneurysms has advantages over a surgical approach. However, the application of coil embolization is sometimes limited in wide-necked posterior inferior cerebellar artery (PICA) aneurysms, which are incorporating the origin of the branch. Presented here is a series of patients who were subjected to stent-supported coil embolization of PICA aneurysms.

Methods

From a prospective data repository, we retrieved records of seven consecutive patients with PICA aneurysms, all of whom were treated by stent-assisted coil embolization between January 2010 and November 2012. Outcomes were analyzed in terms of aneurysm morphology and clinical status.

Results

In all seven instances, the stents were placed from proximal PICA to vertebral artery (VA). A retrograde approach, via contralateral VA, was performed in five patients, where the origin of PICA from VA assumed an acute angle. In the other two patients, where the angles were obtuse, the stenting was done antegrade, via ipsilateral VA. Out of five patients with retrograde approach, single puncture and a single guiding catheter sufficed in three patients, whereas the remaining two patients required dual puncture and two guiding catheters. Endovascular treatments, as performed, resulted in excellent outcomes for all seven patients, although an asymptomatic thrombus developed in one patient with a ruptured aneurysm.

Conclusion

For coil embolization of PICA aneurysm requiring stent protection, either ipsilateral or contralateral VA access routes may be used, depending on the angle of PICA origin and the configuration of the aneurysm.     

Retreatment of previously embolized cerebral aneurysms: the risk of further coil embolization does not negate the advantage of the initial embolization

BACKGROUND AND PURPOSE: A significant minority of aneurysms treated by endovascular means undergo additional subsequent therapy to treat aneurysm recurrence. Our study was undertaken to determine the risk of additional coil embolization of aneurysms recurring following endovascular therapy.MATERIALS AND METHODS: Patients were identified during a 10-year period from prospectively collated data bases at 2 different neuroscience institutions. Patient outcome was obtained from the data bases or the patient''s neurosurgical records. Occlusion grade was assessed at the time of treatment and at follow-up angiography as complete, near-complete, or incomplete.RESULTS: Of a total of 1834 aneurysms in 1631 patients, 100 aneurysms in 99 patients treated between January 1996 and December 2005 required additional coiling because of an enlarging remnant and subtotal occlusion. This comprised 6% of the patients treated and 8% of the total followed. Thromboembolic events complicated 3 retreatment procedures, but all 3 patients remain independent. Ninety-five patients were followed for 8–103 months (mean, 42.3 months) by conventional or MR angiography.CONCLUSION: Coil embolization of aneurysm recurrences has a low complication rate and leads to satisfactory occlusion in most cases. The risk from additional coil embolization does not negate the advantage of the initial embolization.

Coiling of ruptured intracranial aneurysms achieves an absolute reduction in death or dependence at 1 year of 7.4% and a relative risk reduction of 23.9% when compared with neurosurgical clipping.1 The main concern is the durability of endovascular treatment. Aneurysm recurrence is potentially disadvantageous. Our knowledge of the long-term natural history of a coiled aneurysm remnant is incomplete. Rebleeding, though uncommon, is well recognized.2–5 Our aim was to determine the complication rate of additional coil embolization in previously coiled aneurysms with unruptured remnants. Because the rupture risk from aneurysm recurrences is very low, it is essential that retreatment be effective and carry only a small additional burden of morbidity.     

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.     

Does stent type impact coil embolization outcomes in extended follow-up of small-sized aneurysms (&lt; 10 mm)?

Purpose

Self-expandable stents have enabled endovascular treatment of wide-necked aneurysms (ordinarily viewed as technically prohibitive), with favorable outcomes. However, the impact of stent type on occlusive stability has not been adequately investigated. In small-sized unruptured saccular aneurysms, we generated estimates of stent-assisted coil embolization outcomes during follow-up monitoring. Stent type and other risk factors linked to recanalization were analyzed.

Methods

A cohort of 286 patients harboring 312 small-sized unruptured aneurysms (<?10 mm) was subjected to mid-term and extended follow-up monitoring after stent-assisted coiling. Three types of stents (Enterprise, 192; Neuroform, 27; LVIS, 93) were deployed in this population; all medical records and radiologic data of which were reviewed. Mid-term recanalization rates and related risk factors were assessed using binary logistic regression analysis.

Results

A total of 49 aneurysms (15.7%) displayed recanalization at 6 months postembolization, with 34 and 15 instances of minor and major recanalization, respectively. Multivariate analysis indicated that wide-necked aneurysms (>?4 mm) (HR?=?2.362; p?=?0.017), incomplete occlusion at time of coiling (HR?=?2.949; p?=?0.002), and stent type (p?=?0.048) were significant factors in mid-term recanalization, whereas hypertension (p?=?0.095) and packing density ≤?30% (p?=?0.213) fell short of statistical significance. Compared with Enterprise (HR?=?2.828) or Neuroform (HR?=?4.206) stents, outcomes proved more favorable with use of LVIS.

Conclusions

Above findings demonstrate that in addition to occlusive status at time of coil embolization and neck size, stent type may affect follow-up outcomes of stent-assisted coil embolization in small-sized aneurysms. LVIS (vs Enterprise or Neuroform stents) performed best during follow-up monitoring in terms of limiting recanalization.

     

Endovascular treatment of proximal superior middle cerebral artery aneurysms

Introduction

Aneurysms superiorly located on the proximal segment of the middle cerebral artery (PMCAA) are rare and challenging to treat. No information is available regarding their management by endovascular approach. The aim of this study was to report our experience with endovascular treatment (EVT) of PMCAA.

Methods

A retrospective review of our prospectively maintained database identified all PMCAA treated in our institution. The clinical charts, procedural data, and angiographic results were reviewed.

Results

From April 2004 to December 2011, 17 patients were identified including six who presented with subarachnoid hemorrhage (SAH) and 11 with an unruptured PMCAA. All aneurysms were small (<6?mm) and had a branch arising from the neck or the sac, and 15/17 were wide-necked. All patients were successfully treated by balloon-assisted coiling (n?=?10), stent-assisted coiling (n?=?5), and coiling (n?=?2). No technical or clinical complication occurred. Fifteen patients showed an excellent clinical outcome, and two kept a slight or a significant deficit that were both SAH-related. Immediate anatomical outcome includes nine complete occlusions and eight neck remnants. Imaging follow-up in 11 patients (mean?=?21, range, 6 to 60?months) showed stable or improved results in all cases.

Conclusion

Our study is the first reported series of patients with PMCAA treated by selective embolization. It suggests that EVT is a safe and effective alternative to surgery for the management of PMCAA. Balloon- or stent-assisted coiling are needed in most cases because of PMCAA morphological characteristics.