Microsurgical management of incompletely coiled and recurrent aneurysms: trends, techniques, and observations on coil extrusion

Surgical Clipping of Previously Coiled Recurrent Intracranial Aneurysms: A Single-Center Experience

Objective: This study reviews our experiences in surgical clipping of previously coiled aneurysms, emphasizing on recurrence mechanism of intracranial aneurysms (IAs) and surgical techniques for different types of recurrent IAs.

Method: We performed a retrospective study on 12 patients who underwent surgical clipping of aneurysms following endovascular treatment between January 2010 and October 2020. The indications for surgery, surgical techniques, and clinical outcomes were analyzed.

Result: Twelve patients with previously coiled IAs were treated with clipping in this study, including nine females and three males. The reasons for the patients having clipping were as follows: early surgery (treatment failure in two patients, postoperative early rebleeding in one patient, and intraprocedural aneurysm rupture during embolization in one patient) and late surgery (aneurysm recurrence in five patients, SAH in one, mass effect in one, and aneurysm regrowth in one). All aneurysms were clipped directly, and coil removal was performed in four patients. One patient died (surgical mortality, 8.3%), 1 patient (8.3%) experienced permanent neurological morbidity, and the remaining 10 patients (83.4%) had good outcomes. Based on our clinical data and previous studies, we classified the recurrence mechanism of IAs into coil compaction, regrowth, coil migration, and coil loosening. Then, we elaborated the specific surgical planning and timing of surgery depending on the recurrence type of IAs.

Conclusion: Surgical clipping can be a safe and effective treatment strategy for the management of recurrent coiled IAs, with acceptable morbidity and mortality in properly selected cases. Our classification of recurrent coiled aneurysms into four types helps to assess the optimal surgical approach and the associated risks in managing them.

The evolution of intracranial aneurysm treatment techniques and future directions

Treatment techniques and management guidelines for intracranial aneurysms (IAs) have been continually developing and this rapid development has altered treatment decision-making for clinicians. IAs are treated in one of two ways: surgical treatments such as microsurgical clipping with or without bypass techniques, and endovascular methods such as coiling, balloon- or stent-assisted coiling, or intravascular flow diversion and intrasaccular flow disruption. In certain cases, a single approach may be inadequate in completely resolving the IA and successful treatment requires a combination of microsurgical and endovascular techniques, such as in complex aneurysms. The treatment option should be considered based on factors such as age; past medical history; comorbidities; patient preference; aneurysm characteristics such as location, morphology, and size; and finally the operator’s experience. The purpose of this review is to provide practicing neurosurgeons with a summary of the techniques available, and to aid decision-making by highlighting ideal or less ideal cases for a given technique. Next, we illustrate the evolution of techniques to overcome the shortfalls of preceding techniques. At the outset, we emphasize that this decision-making process is dynamic and will be directed by current best scientific evidence, and future technological advances.

Flow diverter stents in the treatment of recanalized intracranial aneurysms

BACKGROUND

We assessed the safety and efficacy of flow diverter stents (FDSs) in the treatment of recanalized or residual intracranial aneurysms treated endovascularly.

MATERIALS & METHODS

Patients whose recanalized or residual aneurysms were treated with FDSs in five tertiary hospitals were reviewed retrospectively. The patients' demographic data, aneurysm characteristics, types of previous treatment, and clinical complications, or serious adverse events associated with FDSs, as well as the results of neurological and angiographic follow-up assessments, were recorded.

RESULTS

Eighty-six patients (37 males) with 87 aneurysms were included in this study. Eighty (91.9%) aneurysms were in the anterior and seven (8.1%) in the posterior circulation. The initial treatment methods were the primary coiling or balloon remodeling technique in 69 (79.3%) and stent-assisted coiling in 18 (20.7%) aneurysms. The endovascular procedure was successful in all patients. Complications occurred in four patients, for a total complication rate of 4.6%. A technical complication developed in one patient (1.2%). An in-stent thrombosis treated with tirofiban was seen in two cases. Late in-stent stenosis exceeding 50% was treated with balloon angioplasty in one patient. The mean length of follow-up was 21.0 months. The first angiographic follow-up (3-6 months) revealed the complete occlusion of 74 aneurysms (85.1%). While 76 aneurysms (87.4%) were occluded at the last angiographic follow-up (mean: 26.0 months), 11 aneurysms (12.6%) were still filling. Morbimortality was zero.

CONCLUSION

The drawback of endovascular treatment is aneurysmal remnants or recurrences, which is safely and durably amenable to flow diversion.

Microsurgical treatment for the recurrent cerebral aneurysm initially treated using coil embolization

OBJECTIVE

Microsurgical treatment could be a good alternative for the treatment of recurrent cerebral aneurysm after coil embolization. The purpose of this study was to present our experience of microsurgical treatment for recurrent cerebral aneurysm previously treated using coil embolization.

METHODS

From June 2012 to May 2019, 34 patients consecutively received microsurgical treatment for a recurrent cerebral aneurysm previously treated using coil embolization after it ruptured.

RESULTS

Of the 34 patients with aneurysm, 33 had the aneurysm located in the anterior circulation. The most common location was the anterior communicating artery (13 cases). Immediate radiologic outcome at coil embolization was completed (n=6), residual neck (n=26), and residual sac (n=2). The reason for microsurgical treatment included rebleeding (n=12), persistent residual sac (n=1), and recurrence on follow-up study (n=21). Rebleeding occurred within 10 days after coil embolization in 10 cases, and the other 2 were due to regrowth. In the 20 recurred and saccular aneurysms, coil compaction was present in 11 aneurysms and regrowth in 9 aneurysms. Simple neck clipping (n=29) and clipping with coil mass extraction (n=3) was possible in the saccular aneurysms. The blood blister like aneurysm (n=2) were treated using bypass and endovascular internal carotid artery trapping. In the follow-up study group after microsurgical treatment there were no severe complications due to the treatment. Age, cause of retreatment, and modified Rankin Scale before microsurgery were associated with good outcome (p<0.001).

CONCLUSIONS

Microsurgical treatment may be a viable and effective option for treating recurrent aneurysms previously treated by endovascular techniques.

Microsurgery of residual or recurrent complex intracranial aneurysms after coil embolization - a quest for the ultimate therapy

The long-term stability of coil embolization (CE) of complex intracranial aneurysms (CIAs) is fraught with high rates of recanalization. Surgery of precoiled CIAs, however, deviates from a common straightforward procedure, demanding sophisticated strategies. To shed light on the scope and limitations of microsurgical re-treatment, we present our experiences with precoiled CIAs. We retrospectively analysed a consecutive series of 12 patients with precoiled CIAs treated microsurgically over a 5-year period, and provide a critical juxtaposition with the literature. Five aneurysms were located in the posterior circulation, 8 were large-giant sized, 5 were calcified/thrombosed. One presented as a dissecting-fusiform aneurysm, 9 ranked among wide neck aneurysms. Eight lesions were excluded by neck clipping (5 necessitating coil extraction); 1 requiring adjunct CE. The dissecting-fusiform aneurysm was resected with reconstruction of the parent artery using a radial artery graft. Three lesions were treated with flow alteration (parent artery occlusion under bypass protection). Mean interval coiling-surgery was 4.6 years (range 0.5-12 years). Overall, 10 aneurysms were successfully excluded; 2 lesions treated with flow alteration displayed partial thrombosis, progressing over time. Outcome was good in 8 and poor in 4 patients (2 experiencing delayed neurological morbidity), and mean follow-up was 24.3 months. No mortality was encountered. Microsurgery as a last resort for precoiled CIAs can provide-in a majority of cases-a definitive therapy with good outcome. Since repeat coiling increases the complexity of later surgical treatment, we recommend for this subgroup of aneurysms a critical evaluation of CE as an option for re-treatment.

Contrast Enhancement of Intracranial Aneurysms on 3T 3D Black-Blood MRI and Its Relationship to Aneurysm Recurrence following Endovascular Treatment

BACKGROUND AND PURPOSE

Endovascular treatment of intracranial aneurysms aims at preventing aneurysm rupture. Contrast-enhanced black-blood MR imaging facilitates imaging of the vessel walls and the aneurysmal sac contents and is therefore suitable for studying the healing process. This study aims to describe imaging findings of aneurysmal contrast enhancement following endovascular treatment and its correlation to recurrence and elapsed time since coiling.

MATERIALS AND METHODS

Patients undergoing MR imaging follow-up after endovascular treatment of an intracranial aneurysm were included. Contrast-enhanced black-blood T1WI was acquired. Aneurysm wall and intra-aneurysmal enhancement were independently assessed by 2 neuroradiologists and were related to the time elapsed since coiling and the presence of recurrence.

RESULTS

Thirty aneurysms in 30 patients were included. The median time elapsed since treatment was 417 days (interquartile range, 189-1273 days). Aneurysmal contrast enhancement was seen in 24/30 (80%) aneurysms. Enhancement inside the sac in 55% (n = 17), the wall in 23% (n = 7), at the dome (n = 1), or at the base (n = 6) was observed. No statistically significant correlation between aneurysmal contrast enhancement and the elapsed time (P = .83) and presence of a recurrence (P = .184) was detected. In 28/30 patients, the images were of adequate diagnostic quality. Stent implants caused negligible image artifacts.

CONCLUSIONS

Intra-aneurysmal contrast enhancement following endovascular treatment of intracranial aneurysms is a common finding and likely reflects the healing process. A long-term study to examine changes occurring with time and their association with packing density, type of coils (bare platinum versus bioactive coils), and aneurysm recurrence is underway (German Clinical Trials Register, DRKS-ID: DRKS00014644).

Management of Recurrent Aneurysms after Endovascular Coiling: A Fujita Experience

Introduction:

Microsurgical clipping and Endovascular coiling (EC) are both effective alternatives in the management of intracranial aneurysms. EC has been shown to be associated with the risk of recurrent aneurysm (RA) growth. Considering the minimally invasive nature of this procedure, the management of intracranial aneurysms has been skewed toward EC, especially in the developed world. In this scenario, there has been an upsurge of RAs after EC. Since the optimal management of these RAs has not been defined, they pose a unique challenge to the treating surgeons.

Aims and Objectives:

The aim of this study is to elucidate the optimal management of RAs after EC.

Materials and Methods:

Medical records of all patients who underwent surgery for RAs were reviewed from the period January 2014 to March 2019. The demographic and angiographic patterns of the patients and operative techniques and complications were studied. The outcome was dichotomized into good and bad depending on the Glasgow outcome scale (GOS).

Results:

There were four cases of RAs operated in our institution between the above-mentioned period. There were varied differences between the initial coiling and time to recurrences. All four patients were operated under neuromonitoring. Three underwent clipping and one patient underwent clipping with bypass. All four patients had good outcome with a GOS of 5/5.

Conclusion:

Operations for RAs constitute many technical challenges and require a lot of expertise. Such surgeries are recommended in high-volume centers, with sufficient experience in both clipping and cerebral bypass.

Combined Endovascular and Microsurgical Hybrid Management of Cerebral Aneurysms: The Preliminary Fujita Experience

Introduction:

A subgroup of complex aneurysms demands multimodal treatment by microscopic and endovascular means. Partial obliteration or remnant postprocedure demands to go further to the other modality.

Materials and Methods:

All patients between July 2016 and January 2017 who had to undergo multimodality measures for complete obliteration of the aneurysms were included in the study. The patients who had either undergone clipping or coiling for their aneurysms, but with incomplete obliteration of the aneurysm, were also included in the study.

Results:

Between July 2016 and January 2017, a total of three patients had to undergo coiling after clipping of the aneurysm for complete obliteration. Two patients had to go for clipping following coiling. All five patients had complete obliteration of the aneurysm sac.

Conclusion:

Both microscopic and endovascular means are complementary measures instead of competing procedures. It is important to realize the technical difficulties when surgical therapy follows initial endovascular treatment. Similarly, coiling a previously clipped aneurysm can be difficult, if the clip obscures normal working projections.

Microsurgical ligation for incompletely coiled or recurrent intracranial aneurysms: a 17-year single-center experience

Background

In this retrospective single-center study, we presented our experience in the microsurgical management of incompletely coiled or recurrent aneurysms after initial endovascular coiling.

Methods

During a 17-year period, 48 patients underwent microsurgical clipping of incompletely coiled or recurrent aneurysms after coiling (Gurian group B). The clinical data, surgical technique, and postoperative outcome were recorded and analyzed.

Results

Before coiling, 42 patients (87.5%) experienced aneurysm rupture. Most of the aneurysms (46/48, 96%) were located in the anterior circulation. After coiling, 6 patients had incompletely coiled aneurysms and 42 patients had recurrent aneurysms, with a mean time of 20.2 months from coiling to recurrence. Coil extrusion occurred in none of the incompletely coiled aneurysms and 71% (30/42) of the recurrent aneurysms. Clipping techniques are direct microsurgical clipping without coil removal in 16 patients, partial coil removal in 14 patients, and total coil removal in 18 patients. Postoperative and follow-up angiography revealed complete occlusion of the aneurysms in all patients. No patient died during postoperative follow-up period (mean, 78.9 months; range, 10-190 months). Good outcomes (GOS of 4 or 5) were achieved in 87.5% (42/48) of the patients at the final follow-up.

Conclusions

Microsurgical clipping is effective for incompletely coiled or recurrent aneurysms after initial coiling. For recurrent aneurysms that have coils in the neck, have no adequate neck for clipping, or cause mass effects on surrounding structures, partial or total removal of coiled mass can facilitate surgical clipping and lead to successful obliteration of the aneurysms.

A coil in the hair-a case report of percutaneous coil migration

Coil migration following cerebral aneurysm treatment has been described and may result in stroke, recurrent aneurysm, or local mass effect. Cerebral coil embolization is also applied in arteriovenous malformations and arteriovenous fistulas, but these pathologies are relatively rare and coil migration is not as well described. Furthermore, these cases are more commonly treated with combinations of multiple modalities to achieve cure. Embolization, surgery, and radiation each have risks and benefits and combinations may have synergistic risks and benefits not seen in monotherapy. We report a case of extravascular and extra-corporeal coil migration after embolization and craniectomy to treat a patient with hemorrhage from an arteriovenous fistula.

Adenosine-Assisted Clipping of Intracranial Aneurysms

BACKGROUND

Temporary parent vessel clip occlusion in aneurysm surgery is not always practical or feasible. Adenosine-induced transient cardiac arrest may serve as an alternative.

METHODS

All patients who underwent microsurgical clipping of intracranial aneurysms under adenosine-induced asystole performed by the author between September 2011 and July 2014 were retrospectively reviewed.

RESULTS

A total of 16 craniotomies were performed and 16 aneurysms were clipped under adenosine-induced asystole (in 8 basilar arteries, 7 internal carotid arteries, and 1 middle cerebral artery) in 14 patients (8 females, 6 males). Seven cases were elective and 7 were performed after subarachnoid hemorrhage. The patients' mean age was 54 years (range, 39-70 years). The indications for adenosine use were proximal control in narrow surgical corridors in 11 cases, aneurysm softening in 4 cases, and aneurysm rupture in 1 case. A single dose was used in 12 patients; 2 patients had multiple boluses. The median (range) total dose was 30 (18-60) mg. Adenosine induced bradycardia with concomitant arterial hypotension in all patients and the majority also had asystole for 5-15 s. Transient cardiac arrhythmias were noted in 1 patient (atrial fibrillation in need of electroconversion after two boluses).

CONCLUSION

Nine clinical scenarios were identified in which adenosine-induced temporary cardiac arrest and deep hypotension was an effective adjunct to temporary clipping during the microsurgical clipping of intracranial aneurysms.

Early experience with the Penumbra SMART coil in the endovascular treatment of intracranial aneurysms: Safety and efficacy

BACKGROUND

Penumbra SMART coils differ from traditional microcoils used for endovascular coil embolization of intracranial aneurysms (IAs) in that they (1) become progressively softer from their distal to proximal end, rather than being of uniform stiffness, (2) have a tight conformational structure, and (3) have a more robust stretch-resistance platform. These properties aid in preventing microcatheter prolapse and coil herniation during coil deployment and in filling small pockets of the aneurysm sac.

OBJECTIVE/METHODS

To determine the safety and efficacy of this device, the records of 17 consecutive patients with IAs treated with SMART coils were retrospectively analyzed.

RESULTS

Thirteen female and four male patients were identified. Eleven patients presented with subarachnoid hemorrhage, four had recurrent aneurysms, and two had incidentally discovered aneurysms. Twelve aneurysms (two of which were recurrent) were treated with stand-alone coiling, three were treated with stent-assisted coiling, and two with flow diversion with adjuvant coiling. Microcatheter prolapse occurred in one case of a recurrent aneurysm, due to mechanical limitations imposed by a stent placed during prior coiling. Raymond-Roy Occlusion Classification (RROC) I or II occlusion was achieved in 12 aneurysms, including all 10 undergoing primary stand-alone coiling. Of the five RROC III occlusions, two were expected given treatment with flow diversion, while the other three occurred in complex, recurrent aneurysms. One patient suffered a thromboembolic complication of unclear clinical significance.

CONCLUSIONS

The Penumbra SMART coil is a safe and effective device for the endovascular treatment of IAs. Follow-up studies are required to establish long-term results.

Intracranial post-embolization residual or recurrent aneurysms: Current management using surgical clipping

Post-embolization residual or recurrent aneurysms (PERRAs) are not rare in patients with intracranial aneurysms treated by embolization. Their occurrence is mainly associated with an increased amount of interventional therapy. Repeated interventional embolization can be applied in some patients with PERRAs, whereas surgical clipping is preferred in other cases that are not suitable for repeated interventional embolization due to the difficulties inherent to this operation. The surgical clipping of PERRAs is very complicated and difficult to perform, and relevant reports are rare. This study offers a review of PERRA treatment using surgical clipping. Retrospective studies have shown that PERRAs are common aneurysms of the anterior and posterior communicating arteries. According to the recurrent characteristics of PERRAs, it is reasonable to categorize PERRAs into three types: type I-coils are compressed, and no embolic material fills the neck of the aneurysm; type II-coils are migrated, and very few coils fill the neck of the aneurysm or the parent artery; and type III-coils are migrated, and multiple coils fill the neck of the aneurysm or the parent artery. Direct clipping can be applied to types I and II PERRAs, whereas trapping, wrapping, or auxiliary revascularization is required in type III PERRAs. Most coils do not require removal unless they interfere with clipping. However, it is necessary to avoid damaging the surrounding adhesive tissue during coil removal. Satisfactory therapeutic outcomes can be achieved by selecting appropriate PERRA cases in which to perform surgical clipping.

Giant pseudoaneurysm originated from distal middle cerebral artery dissection treated by trapping under sensitive evoked potential and motor evoked potential monitoring: Case report and discussion

BACKGROUND

Dissecting giant pseudoaneurysm of the middle cerebral artery (MCA) is a rare lesion often presenting challenges to neurosurgical teams dealing with this specific pathology. Giant pseudoaneurysm originating from a dissecting distal segment of the MCA treated with aneurysm trapping under motor and sensitive evoked potential monitoring with a successful outcome is presented in the article followed by a brief discussion on the subject.

CASE DESCRIPTION

A case of a previously healthy young female patient admitted at the emergency room of Santa Paula Hospital with a history of a sudden headache and syncope, dysphasia, and Grade 4 right hemiparesis due to a large brain hemorrhage secondary to a 25 mm ruptured pseudoaneurysm originated from a distal left MCA dissecting segment is described. Because the patient risked neurological worsening, aneurysm was treated with parent and efferent vessel trapping technique and no changes on the sensitive and motor evoked potential (MEP) from baseline informed on this decision. Hemorrhage was completely drained after aneurysm was secured.

CONCLUSION

Neurophysiological sensitive and MEP monitoring, on this specific case was a valuable tool and informed on the decision of trapping of this large vascular lesion.

The effect of basilar artery bifurcation angle on rates of initial occlusion, recanalization, and retreatment of basilar artery apex aneurysms following coil embolization

BACKGROUND

Arterial bifurcations are common locations for aneurysm development given the altered hemodynamic forces and shear stress variations present at these locations. Recent reports indicate that a wide basilar artery bifurcation angle is an independent predictor of aneurysm development, growth, and subsequent rupture.

METHODS

To determine the effect of basilar artery bifurcation angle on rates of initial occlusion, recanalization, and retreatment of basilar artery apex aneurysms following coil embolization, the records of 46 patients with basilar artery apex aneurysms treated with endovascular coil embolization from 2007 to 2013 were analyzed.

RESULTS

A wide basilar artery bifurcation angle was associated with a Raymond-Roy Occlusion Classification (RROC) III occlusion in univariate analysis, but was not a statistically significant factor in multivariate modeling. An increasing basilar artery bifurcation angle was not associated with aneurysm recanalization or retreatment following coil embolization. Increasing packing density (p < .01) was the only statistically significant predictor of a RROC I or II closure. The initial RROC designation was the most powerful predictor of both eventual aneurysm recanalization (p = .01) and retreatment (p = .02). While increasing aneurysm size (p < .01), increasing aneurysm volume (p < .01), and increasing neck size (p < .01) were associated with wide basilar artery bifurcation angles, neck size (p = .03) was the only statistically significant predictor of basilar artery bifurcation angle on multivariate analyses.

CONCLUSION

Basilar artery bifurcation angle fails to predict rates of initial occlusion, recanalization, and retreatment on multivariate modeling in our series. Basilar artery apex aneurysm neck size independently correlates with basilar artery bifurcation angle.

Outcome of Surgical or Endovascular Treatment of Giant Intracranial Aneurysms, with Emphasis on Age, Aneurysm Location, and Unruptured Aneuryms - A Systematic Review and Meta-Analysis

Background: Designing treatment strategies for unruptured giant intracranial aneurysms (GIA) is difficult as evidence of large clinical trials is lacking. We examined the outcome following surgical or endovascular GIA treatment focusing on patient age, GIA location and unruptured GIA. Methods: Medline and Embase were searched for studies reporting on GIA treatment outcome published after January 2000. We calculated the proportion of good outcome (PGO) for all included GIA and for unruptured GIA by meta-analysis using a random effects model. Results: We included 54 studies containing 64 study populations with 1,269 GIA at a median follow-up time (FU-T) of 26.4 months (95% CI 10.8-42.0). PGO was 80.9% (77.4-84.4) in the analysis of all GIA compared to 81.2% (75.3-86.1) in the separate analysis of unruptured GIA. For each year added to patient age, PGO decreased by 0.8%, both for all GIA and unruptured GIA. For all GIA, surgical treatment resulted in a PGO of 80.3% (95% CI 76.0-84.6) compared to 84.2% (78.5-89.8, p = 0.27) after endovascular treatment. In unruptured GIA, PGO was 79.7% (95% CI 71.5-87.8) after surgical treatment and 84.9% (79.1-90.7, p = 0.54) after endovascular treatment. PGO was lower in high quality studies and in studies presenting aggregate instead of individual patient data. In unruptured GIA, the OR for good treatment outcome was 5.2 (95% CI 2.0-13.0) at the internal carotid artery compared to 0.1 (0.1-0.3, p < 0.1) in the posterior circulation. Patient sex, FU-T and prevalence of ruptured GIA were not associated with PGO. Conclusions: We found that the chances of good outcome after surgical or endovascular GIA treatment mainly depend on patient age and aneurysm location rather than on the type of treatment conducted. Our analysis may inform future research on GIA.

Outcome After Clipping of Unruptured Intracranial Aneurysms Depends on Caseload

OBJECTIVE

Although most neurovascular centers currently have a coil first policy, the percentage of coiled versus clipped aneurysms, as well as treatment outcomes, varies strongly between these centers. This study evaluates the impact of an increase in clipping caseload on treatment outcome in a large single-center series.

METHODS

All consecutive patients who underwent microsurgical clipping of unruptured intracranial aneurysms between January 2003 and April 2014 in our department were analyzed retrospectively. According to the change of the chairman in the neurosurgical department (1 September 2008) with a subsequent increase in the clipping volume, the entire cohort was divided into 2 groups with equal time intervals (historic and current cohorts).

RESULTS

There were 94 clipped unruptured intracranial aneurysms in the historic cohort and 252 in the current cohort. Unfavorable outcome at 6 months postoperatively (defined as modified Rankin Score >2) was observed in 8 cases (8.5%) in the historic cohort and 7 cases (2.8%) in the current cohort (P < 0.0001). The surgical mortality decreased from 3.2% to 0%. Cerebral infarction on postoperative computed tomography scan was observed in 25 cases (26.6%) in the historic cohort and 19 cases (7.5%) in the current cohort (P < 0.0001). Within the current cohort, there was a progressive improvement of surgical outcome over the time.

CONCLUSIONS

The improvement of the surgical outcome after increasing the clipping caseload underlines the importance of sufficient surgical volume for maintenance of competitive treatment results.

Retreatment of Recurrent Internal Carotid-Posterior Communicating Artery Aneurysm after Coil Embolization

Internal carotid-posterior communicating artery (IC-PC) aneurysms account for more than 20% of all intracranial aneurysms. As a result of the increase in coiling, there has also been an increase in recurrent IC-PC aneurysms after coiling. We present our experience of 10 recurrent IC-PC aneurysms after coiling that were retreated using surgical or endovascular techniques in order to discuss the choice of treatment and the points of clipping without removal of coils. From 2007 to 2014, 10 recurrent IC-PC aneurysms after coiling were retreated. When the previous frames covered the aneurysms all around or almost around except a part of the neck, coiling was chosen. In other cases, clipping was chosen. Clipping was attempted without removal of coils when it was technically feasible. Among the 10 IC-PC aneurysms retreated, 3 were retreated with coiling and 7 were retreated with clipping. In all three cases retreated with coiling, almost complete occlusion was accomplished. In the seven cases retreated with clipping, coil extrusion was observed during surgery in six cases. In most of them, it was necessary to dissect strong adhesions around the coiled aneurysms and to utilize temporary occlusion of the internal carotid artery. In all seven cases, neck clipping was accomplished without the removal of coils. There were no neurological complications in any cases. The management of recurrent lesions of embolized IC-PC aneurysms requires appropriate choice of treatment using both coiling and clipping. Clipping, especially without the removal of coils, plays an important role in safe treatment.

Combined endovascular and microsurgical management of complex cerebral aneurysms

Cerebral aneurysms are associated with a 50% mortality rate after rupture and patients can suffer significant morbidity during subsequent treatment. Neurosurgical management of both ruptured and unruptured aneurysms has evolved over the years. The historical practice of using microsurgical clipping to treat aneurysms has benefited in the last two decades from tremendous improvement in endovascular technology. Microsurgery and endovascular therapies are often viewed as competing treatments but it is important to recognize their individual limitations. Some aneurysms are considered complex, due to several factors such as aneurysm anatomy and a patient’s clinical condition. A complex aneurysm often cannot be completely excluded with a single approach and its successful treatment requires a combination of microsurgical and endovascular techniques. Planning such an approach relies on understanding aneurysm anatomy and thus should routinely include 3D angiographic imaging. In patients with ruptured aneurysms, endovascular coiling is a well-tolerated early treatment and residual aneurysms can be treated with intervals of definitive clipping. Microsurgical clipping also can be used to reconstruct the neck of a complex aneurysm, allowing successful placement of coils across a narrow neck. Endovascular techniques are assisted by balloons, which can be used in coiling and testing parent vessel occlusion before sacrifice. In some cases microsurgical bypasses can provide alternate flow for planned vessel sacrifice. We present current paradigms for combining endovascular and microsurgical approaches to treat complex aneurysms and share our experience in 67 such cases. A dual microsurgical–endovascular approach addresses the challenge of intracranial aneurysms. This combination can be performed safely and produces excellent rates of aneurysm obliteration. Hybrid angiographic operating-room suites can foster seamless and efficient complementary application of these two modalities.

Complex middle cerebral artery aneurysms: a new classification based on the angioarchitecture and surgical strategies

Background

Because of the diversity of aneurysm morphology, complicated arterial anatomy and hemodynamic characteristics, tailored surgical treatments are required for cases of individual complex middle cerebral artery (MCA) aneurysms.

Methods

During an 8-year period, 59 complex MCA aneurysms in 58 patients were treated microsurgically in our department. Complex aneurysms were defined as having large (10–24 mm in diameter) or giant (diameter ≥ 25 mm) size or non-saccular morphology (fusiform, dissecting or serpentine).

Results

Direct clipping of the aneurysmal necks was achieved in eight patients, while reconstructive clipping was performed in 25 patients. Indirect aneurysm occlusion was performed in 25 cases, including trapping or resecting the aneurysm in four cases, trapping or resecting the aneurysm with extra-intracranial (EC) or intra-intracranial (IC) bypass in 21 cases and internal carotid artery (ICA) sacrifice with EC-IC bypass in one case. Forty-eight aneurysms (81.4 %) were completely obliterated. Graft patency was confirmed in 20 of 21 cases (95.2 %) with bypass. A recurrent aneurysm was detected in one case and a re-operation was performed. Two patients with Hunt-Hess grade IV aneurysms died during the perioperative period. Overall, 52 cases (88.1 %) had good outcomes (Glasgow Outcome Scale ≥ 4) during the late follow-up period.

Conclusion

The surgical modality and strategy for treating complex MCA aneurysm are decided according to the morphology of the aneurysm, vascular anatomy and the hemodynamic characteristics of each case. Thus, we developed a new classification based on the angioarchitecture. Favorable outcomes can be achieved by treating complex MCA aneurysms with appropriate surgical modalities, strategies and techniques.

Incorporation of extruded coils into the third nerve in association with third nerve palsy

The extrusion of the coil complex outside of the aneurysmal dome is thought to be an important mechanism by which the aneurysm neck and fundus recanalize, but the migration of the coil loops and their incorporation inside vital nervous structures has not been clearly described. We reviewed the medical literature on coil extrusion and migration and report a rare case of third nerve palsy due to direct damage caused by coil loop migration that resolved after surgery. A 25-year-old woman presented with subarachnoid hemorrhage and painful left third nerve palsy. The angiogram revealed a supraclinoid internal carotid aneurysm incorporating the origin of the left posterior communicating artery. Her aneurysm was coiled. The 8 month follow-up angiogram revealed a major recurrence of her aneurysm. It was decided to surgically clip the aneurysm. At surgery, coil loops were found in the subarachnoid space and embedded into the third nerve. At 1 month follow-up she had recovered well, and only had very subtle diplopia upon fatigue. Coil extrusion is a fairly common phenomenon that should be suspected in instances of major aneurysmal recurrence. Surgical treatment is recommended, and special care should be taken when mobilizing the extruded coil mass.

Tasuki clipping combined with high flow bypass for ruptured, previously coiled, partially thrombosed giant aneurysm at the carotid bifurcation

A 33-year-old woman presented with a ruptured, partially thrombosed carotid bifurcation aneurysm after partial coiling, which was successfully treated by "tasuki" (a cloth sash crossing from one shoulder to the opposite hip, worn by relay marathon runners) clipping combined with radial artery and external carotid artery-to-middle cerebral artery bypass. "Tasuki" clipping can overcome the dilemma between achieving early complete thrombosis in the blind sac and maintaining anterograde flow of the parent artery to prevent inadvertent occlusion of the perforators and anterior choroidal artery.

Review of 2 decades of aneurysm-recurrence literature, part 1: reducing recurrence after endovascular coiling

SUMMARY

Angiographic recurrence following endovascular therapy is an indirect measure of the potential for hemorrhage. Because patients and physicians consider recurrence to be a suboptimal outcome with some chance of future hemorrhage, much effort has been expended to reduce the incidence of recurrence. The literature regarding aneurysm recurrence following endovascular therapy, spanning 2 decades, is extensive. We will review and summarize the effort to reduce recurrence following endovascular treatment of cerebral aneurysms.

The retreatment: indications, technique and results

Durability of endovascular treatment of intracranial aneurysms has always been an issue and a very strong point of criticism. Although studies on long-term results have made it clear that endovascular treatment safe and effective they, nonetheless showed retreatment after endovascular treatment is nearly 5-10 times more frequent than surgical clipping. Risk factors predisposing high probability of retreatment are aneurysm with dissecting nature, incomplete coiling, sac size larger than 10mm and localization at the bifurcations such as basilar tip. The indications for retreatment after endovascular treatment are not clear yet, although certain morphologic criteria can be used. Retreatment appears not to negate the initial advantage of endovascular treatment over surgical treatment and can be performed very small morbi-mortality numbers.

Microsurgical clipping of previously coiled intracranial aneurysms

OBJECTIVE

Endovascular coiling techniques for the treatment of intracranial aneurysms have rapidly developed as an alternative option to surgical clipping. A distinct problem after endovascular coiling is the management of a residual aneurysm neck due to incomplete filling, compaction of coils or regrowth of the aneurysm. Treatment options in this situation include surgical clipping, re-coiling, stent implantation or observation.

METHODS

From June 2006 to August 2011, 15 patients underwent surgical clipping of residual or recurrent aneurysms after previous endovascular treatment. The mean age of the patients was 50.6 years (range, 27-85 years). The mean interval between coiling and clipping was 76.5 weeks (range, 0-288 weeks).

RESULTS

Thirteen patients revealed a regrowth of coiled aneurysms, and in 5 patients compaction of coils was present. Coil extrusion was observed in 9 patients intraoperatively. In case of coil obstruction at the aneurysmal neck during surgery, coils were partially or completely removed. In all cases complete occlusion of the aneurysms was surgically achieved.

CONCLUSION

Coiled aneuryms with incomplete occlusion, coil compaction or regrowth of the aneurysmal neck can be successfully treated with microsurgical clipping. Coil extrusion was more often observed intraoperatively than expected. Complete occlusion of the aneurysm can be performed safely, even if loops of coils protrude into the aneurysmal neck. In these cases intraoperative removal of the coils enables secure closure of the aneurysm with a surgical clip.

Surgical nuances of clipping after coiling: looking beyond the international subarachnoid aneurysm trial

After the introduction of Guglielmi Detachable Coils (GDC), endovascular management of ruptured and unruptured aneurysms became a viable alternative to surgical clipping as a "minimally invasive" option. Endovascular management of aneurysms became even more common after the International Subarachnoid Aneurysm Trial, which was one of the first prospective, randomized trials comparing clipping and coiling, showed reduced dependency and death in patients undergoing coiling after two months and one year. As the numbers of patients treated by endovascular therapy grow neurosurgeons are facing increasing challenges of clipping difficult aneurysms not suitable for coiling, including those that are wide-necked, thrombosed or involving many perforators. In addition, treatment failures (recurrent and residual aneurysms after coiling) pose difficult treatment scenarios fraught with complications due to surrounding adhesions, coil migration and involvement of adjacent neurovascular structures. Thus, we analyzed the recent literature dealing with the nuances of clipping after coiling and reviewed the current management principles involved in treating these difficult aneurysms.

Endovascular treatment of recurrent coiled aneurysms: assessment of complications and rebleeding during a decade in a single center

Recurrence is the main drawback of aneurysmal coiling. Additional coiling must sometimes be considered in patients with reopened aneurysms and expose the patient to the risk of a new procedure. Our purpose was to assess the procedural complications of additional endovascular treatments in patients with previously coiled but recurrent aneurysms treated by two neurointerventionalists during a decade in a single center. Between 1999 and 2009, 637 intracranial aneurysms were coiled and had a clinical and angiographic follow-up at our institution. Following the first embolization, 44 aneurysms were retreated with coils and 11 were retreated a second time. Retreatment was decided when a recurrence showed at angiographic follow-up. Early retreatments, performed in the first month after an incomplete or failed initial coiling, were excluded. We retrospectively analysed the procedural complications, rebleeding, clinical and angiographic outcomes of the retreatments. No death or bleeding occurred in these 55 additional procedures. We had three periprocedural thromboembolic complications and the procedural permanent morbidity was 1.8%. Clinical and angiographic follow-ups ranged from six months to nine years (mean: 37 months, median: 36 months). Thirty-seven of the 44 retreated aneurysms (84%) showed a stable occlusion at follow-up. Seven showed a recurrence but were not retreated due to the stability of the packing. No rebleeding was observed during the follow-up period. Our results show that endovascular treatment of recurrent aneurysms is associated with a low procedural risk.

Incidence of subarachnoid haemorrhage: an Australian national hospital morbidity database analysis

Incidences of subarachnoid haemorrhage (SAH) in Australia have been reported in regional studies with variable rates. We investigated the national SAH rate and evaluated the trend over the 10 years from 1998 to 2008. The crude SAH incidence, not related to trauma or arteriovenous malformation, was estimated at 10.3 cases per 100,000 person-years (95% confidence interval [CI]: 10.2-10.4). Females have a higher incidence of SAH (12.5 cases per 100,000; 95% CI: 12.3-12.8) compared to males (8.0 cases per 100,000; 95% CI: 7.8-8.3), with age-adjusted incidence increases with increasing age for both sexes. Less than 10% of SAH occurred in the first three decades of life. The peak age group for patients to experience SAH was between 45 years and 64 years, accounting for almost 45% of the overall annual SAH admissions. Aneurysms located in the anterior circulation were a more common source of rupture compared to those located in the posterior circulation (rate ratio 3.9; 95% CI: 3.6-4.2). Contrary to contemporary observations in the literature, we did not observe a decline in the incidence of SAH during this specified study period.

Comparison of 2-year angiographic outcomes of stent- and nonstent-assisted coil embolization in unruptured aneurysms with an unfavorable configuration for coiling

BACKGROUND AND PURPOSE

Stents are known to have hemodynamic and biologic effects in addition to their mechanical scaffold effect. To determine whether stents affect long-term outcomes after coiling of unruptured aneurysms, we compared angiographic outcomes at 2 years postembolization for stent- and nonstent-assisted coiled unruptured aneurysms.

MATERIALS AND METHODS

Stent-assisted coiling was used in unruptured aneurysms unfavorable for simple coiling (neck size >4 mm and dome-to-neck ratio <1.5) in our practice. Therefore, 126 coiled unruptured aneurysms in total (40 [31.7%] stent group and 86 [68.3%] nonstent group) with these conditions were selected for this study. The nonstent group aneurysms were treated with multiple microcatheter technique (53 cases) or balloon-assisted technique (33 cases). Self-expandable stents were used for coiling in stent group aneurysms. No significant difference in aneurysmal characteristics (aneurysm type [sidewall/bifurcation], diameter, neck size, and dome-to-neck ratio) or angiographic outcome at embolization (packing attenuation, obliteration grade, and contrast filling) were observed between the 2 study groups.

RESULTS

At 2-year follow-up visits, rates of progressive occlusion (stent group, 17/40 [42.5%] versus nonstent group, 34/86 [39.5%]) and recanalization (7/40 [17.5%] versus 18/86 [21.0%]) did not show a statistically significant difference between the 2 groups (P = .895).

CONCLUSIONS

The present study did not show that additional hemodynamic and biologic effects of stents designed for neck remodeling were enough to enhance progressive occlusion and prevent the recanalization of unruptured aneurysms. Our finding suggests that stent placement provides no better long-term angiographic outcomes for unruptured aneurysms with an unfavorable configuration for coiling.

Extruded platinum coils from recurrent previously coiled intracranial aneurysms discovered at the time of microsurgical clip ligation. A report of three cases

CE of brain aneurysms is safer with better outcomes than microsurgical clip ligation. However, the higher recurrence rate may nullify the acute benefits of coiling. Reported here are three patients who underwent surgery to treat their recurrent, previously coiled aneurysm. Intraoperatively, coils were seen extruding from the recurrent regions of each aneurysm and adherent to the surrounding neurovascular structures. These interesting findings question the premise that observation of a recurrent aneurysm is safe.