Neurosurgical treatment for aneurysm remnants or recurrences after coil occlusion

Microsurgical Treatment of Previously Coiled Giant Aneurysms: Experience with 6 Cases and Literature Review

OBJECTIVE

Surgical treatment of insufficiently embolized (coiled) or recurrent giant aneurysms has not been well established in the literature. The aim of this study is to bring up the surgical difficulties of these rare aneurysms and to offer solutions.

METHODS

A database was queried for giant aneurysms that had been previously embolized and subsequently required surgical treatment. We only found 29 aneurysms in the literature and here, we report 6 more surgical cases with patient characteristics, radiological studies, applied surgical techniques, and outcomes which were reviewed retrospectively.

RESULTS

Four females and 2 males, with a mean age of 45.6 years took part in the study. The most common aneurysm location was the middle cerebral artery. While 5 aneurysms were successfully clipped, 1 was excised and the neck was closed with micro sutures. The coils were compulsorily removed in 3 patients. Postoperative digital subtraction angiography confirmed total occlusion of the aneurysms in all cases. Overall morbidity was 16.6%. There was no mortality. No recurrence was observed in the angiographic follow-up (mean 22.6 months, range 7-47 months). The literature review also determined that 97.1% of 35 previously coiled giant aneurysms (including ours) were occluded using various surgical techniques, with 82.8% good outcome.

CONCLUSIONS

Surgical clipping is a safe and effective procedure for the treatment of insufficiently embolized or recurrent giant aneurysms after coiling. If possible, the coils should not be removed. However, if safe clipping is not possible due to the coils, the removal of the coils should not be avoided.

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.

Microsurgery of Giant Intracranial Aneurysm: A Single Institution Outcome Study

Background

Giant intracranial aneurysms (GIAs) are treacherous lesions and in spite of the many advances, endovascular therapy (EVT) of GIAs is challenging.

Objective

A retrospective analysis of our results with microsurgery of GIAs is presented to examine the role of microsurgery in the current trend of EVT.

Materials and Methods

Between 1996 and 2019, 134 patients with 147 GIAs had microsurgery by the senior author in a single institute. The medical and imaging records for all the patients were reviewed. The patient outcome was determined by modified Rankin scale (mRS); ≤3 was considered as a good outcome. Statistical analysis was done using the SPSS program and odds ratios and their 95% confidence intervals were computed; a probability value of < 0.05 was considered significant.

Results

There were 123 aneurysms (83.7%) in the anterior circulation and 24 aneurysms (16.3%) in the posterior circulation. Overall 103 out of 134 (76.8%) patients had a good outcome postoperatively. Good preoperative mRS score (≤3) had an overall good prognosis in the postoperative period and was statistically significant (P = 0.000, odds ratio: 0.036, 95% CI: 0.008-0.171). Presence of subarachnoid hemorrhage (SAH) was also statistically significant for good outcome (P = 0.04, odds ratio: 2.898, 95% CI: 1.051-7.991), but age was not a significant prognostic factor. Mortality within 30 days of treatment was 4.47%.

Conclusion

GIAs need treatment because of their dismal natural history. Results of microsurgical treatment by a single surgeon of the large current series compare well with the results of EVT and justifies pursuing microsurgery for GIAs.

Definitive Treatment With Microsurgical Clipping After Recurrence and Rerupture of Coiled Anterior Cerebral Artery Aneurysms

BACKGROUND

The extent of obliteration of ruptured intracranial aneurysms treated with coil embolization has been correlated with the risk of rerupture. However, many practitioners consider that a small neck remnant is unlikely to result in significant risk after coiling.

OBJECTIVE

To report our recent experience with ruptured anterior cerebral artery aneurysms treated with endovascular coiling, which recurred or reruptured, requiring microsurgical clipping for subsequent treatment.

METHODS

Retrospective review of patients with intracranial aneurysms treated at our institution since August 2018. Patient and aneurysm characteristics, initial and subsequent treatment approaches, and outcomes were reviewed.

RESULTS

Six patients were included. Out of those 6 patients, 5 patients had anterior communicating artery aneurysms, and 1 patient had a pericallosal aneurysm. All initially presented with subarachnoid hemorrhage (SAH) and were treated with coiling. Recurrence occurred at a median of 7.5 mo. In 2 cases, retreatment was initially performed with repeat endovascular coiling, but further recurrence was observed. Rerupture from the residual or recurrent aneurysm occurred in 3 cases. In 2 cases, the aneurysm dome recurred; in 1 case, rerupture occurred from the neck. All 6 patients underwent treatment with microsurgical clipping. Follow-up catheter angiography demonstrated a complete occlusion of the aneurysm in all cases with the preservation of the parent vessel.

CONCLUSION

Anterior cerebral artery aneurysms may recur after endovascular treatment, and even small neck remnants present a risk of rerupture after an initial SAH. Complete treatment requires a complete exclusion of the aneurysm from the circulation. Even in cases that have been previously coiled, microsurgical clipping can represent a safe and effective treatment option.

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.

Management of recurrent intracranial aneurysms after coil embolization: a novel classification scheme based on angiography

OBJECTIVE

Recurrent aneurysms after coil embolization remain a challenging issue. The goal of the present study was to report the authors' experience with recurrent aneurysms after coil embolization and to discuss the radiographic classification scheme and recommended management strategy.

METHODS

Aneurysm treatments from a single institution over a 6-year period were retrospectively reviewed. Ninety-seven aneurysms that recurred after initial coiling were managed during the study period. Recurrent aneurysms were classified into the following 5 types based on their angiographic characteristics: I, pure recanalization inside the aneurysm sac; II, pure coil compaction without aneurysm growth; III, new aneurysm neck formed without coil compaction; IV, new aneurysm neck formed with coil compaction; and V, newly formed aneurysm neck and sac.

RESULTS

Aneurysm recurrences resulted in rehemorrhages in 6 cases (6.2%) of type III-V aneurysms, but in none of type I-II aneurysms. There was a significantly higher proportion of ophthalmic artery aneurysms and complex internal carotid artery aneurysms presenting as types I and II than presented as the other 3 types (63.3% vs 16.4%, p < 0.001). In contrast, for posterior communicating artery aneurysms and anterior communicating artery aneurysms, a higher proportion of type III-V aneurysms was observed than for the other 2 types, but without a significant difference in the multivariate model (56.7% vs 23.3%). In addition, giant (> 25 mm) aneurysms were more common among type I and II lesions than among type III and IV aneurysms (36.7% vs 9.0%, p = 0.001), which exhibited a higher proportion of small (< 10 mm) lesions (65.7% vs 13.3%, p < 0.001). A single reembolization procedure was sufficient to occlude 80.0% of type I recurrences and 83.3% of type II recurrences from coil compaction but only 65.6% of type III-V recurrences from aneurysm regrowth.

CONCLUSIONS

Aneurysm size and location represent the determining factors of the angiographic recurrence types. Type I and II recurrences were safely treated by reembolization, whereas type III-V recurrences may be best managed surgically when technically feasible.

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.

Microvascular Revascularization for Recurrent A1 Anterior Cerebral Artery Aneurysm Postendovascular Treatment: A Case Report and Review of the Literature

The recurrence of aneurysms postcoil embolization is a common occurrence. Endovascular coiling has been noted to be more effective for small lesions rather than the giant aneurysms. A postembolization recurrent aneurysm is a difficult condition to manage. We present a case of a recurrent giant aneurysm of the anterior cerebral arteries (ACAs) first segment (A1). It was managed by superficial temporal artery to A3 segment of anterior cerebral artery bypass anastomotic revascularization plus distal A1- segment clipping. A literature review is presented for the management of giant A1 artery aneurysms.

Outcomes of Retreatment for Intracranial Aneurysms — A Meta-Analysis

BACKGROUND

Long-term results from the International Subarachnoid Hemorrhage Trial (ISAT) and Barrow Ruptured Aneurysm Trial (BRAT) indicate considerably higher retreatment rates for aneurysms treated with coiling compared to clipping, but do not report the outcome of retreatment.

OBJECTIVE

To evaluate retreatment related outcomes.

METHODS

A meta-analysis in accordance with PRISMA guidelines was conducted using Medline search engines PubMed and EMBASE to identify articles describing outcomes after retreatment for intracranial aneurysms. Pooled prevalence rates for complete occlusion rate and mortality were calculated. Outcomes of different treatment and retreatment combinations were not compared because of indication bias.

RESULTS

Twenty-five articles that met the inclusion criteria were included in the meta-analysis. Surgery after coiling had a pooled complete occlusion rate of 91.2% (95% confidence interval [CI]: 87.0-94.1) and a pooled mortality rate of 5.6% (95% CI: 3.7-8.3). Coiling after coiling had a pooled complete occlusion rate of 51.3% (95% CI: 22.1-78.0) and a pooled mortality rate of 0.8% (95% CI: 0.15-3.7). Surgery after surgery did not provide a pooled estimate for complete occlusion as only one study was identified but had a pooled mortality rate of 5.9% (95% CI: 3.1-11.2). Coiling after surgery had a pooled complete occlusion rate of 56.1% (95% CI: 11.4-92.7) and a pooled mortality rate of 9.3% (95% CI: 4.1-19.9). All pooled incidence rates were produced using random-effect models.

CONCLUSION

Surgical retreatment was associated with a high complete occlusion rate but considerable mortality. Conversely, endovascular retreatment was associated with low mortality but also a low complete occlusion rate.

Surgical Clipping of Previously Ruptured, Coiled Aneurysms: Outcome Assessment in 53 Patients

BACKGROUND

Occasionally, previously coiled aneurysms will require secondary treatment with surgical clipping, representing a more complicated aneurysm to treat than the naïve aneurysm. Patients who initially presented with a ruptured aneurysm may pose an even riskier group to treat than those with unruptured previously coiled aneurysms, given their potentially higher risk for rerupture. The objective of this study was to assess the clinical outcomes of patients who undergo microsurgical clipping of ruptured previously coiled cerebral aneurysms. In addition, we present a thorough review of the literature.

METHODS

A total of 53 patients from a single institution who initially presented with a subarachnoid hemorrhage and underwent surgical clipping of a previously coiled aneurysm between December 1997 and December 2014 were studied. Clinical features, hospital course, and preoperative and most recent functional status (Glasgow Outcome Scale score) were reviewed retrospectively.

RESULTS

The mean time interval from coiling to clipping was 2.6 years, and mean follow-up was 5.5 years (range, 0.1-14.7 years). Five patients (9.8%) presented with rebleed prior to clipping. Most patients (79.3%, 42/53) experienced good neurologic outcomes. Most showed no change (81%, 43/53) or improvement (13%, 7/53) in functional status after microsurgical clipping. One patient (2%) deteriorated clinically, and there were 2 mortalities (4%).

CONCLUSIONS

Microsurgical clipping of previously ruptured, coiled aneurysms is a promising treatment method with favorable clinical outcomes.

Clipping of Recurrent Cerebral Aneurysms After Coil Embolization

BACKGROUND AND AIMS

To assess the technical points of surgical clipping for recurrent aneurysms after coiling, we examine a consecutive series of 14 patients who underwent re-treatment.

MATERIALS AND METHODS

From 2009 to 2016, 27 recurrent aneurysms after coiling were re-treated with endovascular treatment or surgical clipping. Of these, 14 were re-treated surgically. In cases where the remnant neck was sufficiently large, neck clipping was chosen. Where the remnant neck was too small and the border between the thrombosed and non-thrombosed portion was distinct, partial clipping was chosen. Surgical clipping was attempted without removing the coils when technically feasible.

RESULTS

Among the 14 cases, neck clipping was performed in 11, partial clipping in 2, and trapping with bypass in 1 case. Clipping without removal of coils was accomplished in all cases. No neurological deterioration occurred after surgical clipping in any case.

CONCLUSION

Clipping of recurrent aneurysms after coiling can compensate for the failure of initial endovascular therapy. For clipping without removal of coils, precise evaluation of the remnant neck is required. Bypass surgery is key to treatment in the case of aneurysm trapping.

Microneurosurgical Clip Ligation of Acutely Ruptured Cerebral Aneurysm Immediately Preceded by Intentional Subtotal Endovascular Coil Embolization Under a Single Anesthesia: Observations Using a Deliberate Combined Sequential Treatment Strategy in 13 Cases

BACKGROUND

Endovascular coil embolization and craniotomy with clip ligation are the 2 most commonly used treatments for ruptured cerebral aneurysm. Although coiling maintains the advantages of brevity and complete avoidance of brain retraction and manipulation, clipping offers the benefits of decompression of the injured brain and lower rates of aneurysm recurrence. A combined, immediately sequential treatment strategy for acutely ruptured cerebral aneurysm that simultaneously maximizes the advantages of both techniques, while minimizing their respective disadvantages, may be a useful paradigm.

OBJECTIVE

To demonstrate the complementarity of clipping and coiling in acutely ruptured cerebral aneurysm.

METHODS

Patients with ruptured anterior circulation cerebral aneurysm standing to benefit from brain decompression were treated by a combination of coiling and microneurosurgery in rapid succession, under the same general anesthetic. Surgery consisted of clipping of the aneurysm via either craniotomy or craniectomy with expansion duraplasty in all cases, and ventriculostomy in selected cases.

RESULTS

Coil embolization of the ruptured aneurysm was carried out rapidly and improved the efficiency of subsequent clipping by allowing early unequivocal identification of the aneurysm dome and decreased brain retraction, reducing risk of intraoperative rupture and obviating temporary occlusion. All aneurysms were shown eliminated by postoperative cerebral angiography.

CONCLUSIONS

A deliberate combined treatment strategy that uses clipping immediately preceded by subtotal coiling under a single anesthetic may be ideal for selected ruptured cerebral aneurysms, takes advantage of the unique strengths of both techniques, makes both techniques easier, and maximizes opportunity for brain protection against delayed complications in the prolonged aftermath of aneurysmal subarachnoid hemorrhage.

Surgical management of recurrent aneurysms after coiling treatment

OBJECTIVE

Aneurysms that recur after coiling treatment are difficult to manage. The microsurgical technique in these cases differs significantly from that in regular aneurysm clipping. We present our experience in surgical management of aneurysms that recurred more than 1 month after coiling in a series of 19 patients.

MATERIALS AND METHODS

Between January 2004 and December 2014, 1437 patients were treated surgically for intracranial aneurysms in our institution. We performed a retrospective review of the clinical records, operation videos, and cerebral angiograms. We focused on patients in whom the initial aneurysm was treated by coiling, but the results were incomplete or the aneurysm recurred.

RESULTS

Nineteen patients underwent surgical clipping for recurrent aneurysm more than 1 month after initial coiling treatment. The sex ratio (male:female) was 0.9, and the average age was 51.3 years (range 35-72 years). One aneurysm was classified as giant (≥ 25 mm), two as large (10-25 mm), and 18 as small (≤ 10 mm). A good outcome (Glasgow Outcome Scale 4 or 5) was observed in 16 of 19 patients (84.2%).

CONCLUSION

Microsurgical clipping can be safe and effective in the management of previously coiled residual and recurrent aneurysms.

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.

Fate of Coiled Aneurysms with Minor Recanalization at 6 Months: Rate of Progression to Further Recanalization and Related Risk Factors

BACKGROUND AND PURPOSE

Minor recanalization in coiled aneurysms may remain stable with time or may progress to major recanalization. Our aim was to monitor the aneurysms displaying minor recanalization in imaging studies at 6 months, gauging major recanalization rates and related risk factors through extended follow-up.

MATERIALS AND METHODS

Sixty-five aneurysms (in 65 patients) showing minor recanalization in follow-up imaging at 6 months were reviewed retrospectively. Medical records and radiologic data accruing during extended monitoring (mean, 24.8 ± 8.2 months) were assessed. Univariate and multivariate analyses were conducted to identify risk factors for progression from minor-to-major recanalization.

RESULTS

Progression to major recanalization was observed in 24 (36.9%) of the initially qualifying aneurysms during a follow-up of 112.5 aneurysm-years, for an annual rate of 17.84% per aneurysm-year. Progression was determined chronologically as follows: 14 (58.3%) at 6 months, 8 (33.3%) at 18 months, and 2 (8.4%) at 30 months. Stent deployment significantly decreased the occurrence of major recanalization (OR = 0.22, P = .03), whereas antiplatelet therapy (OR = 0.82, P = .75), posterior location (OR = 0.24, P = .20), and second coiling for recanalized aneurysms (OR = 0.96, P = .96) were unrelated.

CONCLUSIONS

Our analysis determined a 36.9% rate of major recanalization during a follow-up of 112.5 aneurysm-years in coiled aneurysms showing minor recanalization at 6 months. Stent deployment alone conferred a protective effect, preventing further recanalization without additional treatment. Given the fair probability of late major recanalization, aneurysms showing minor recanalization at 6 months should be monitored diligently, particularly in the absence of stent placement.

Selective microsurgical treatment of giant intracranial aneurysms

Giant intracranial aneurysms are defined as greater than 25mm in diameter. They share the same surgical challenges and strategies as so-called complex aneurysms, sometimes smaller in size but presenting with similar complex anatomy. The surgical difficulties arise from the size of the sack, the presence of intraluminal thrombus, the thickness of the arterial wall, and the complexity of arterial branching on the neck. Preoperative imaging gathers complementary information from magnetic resonance imaging, computed tomographic angiography, and rotational catheter-based angiography with three-dimensional reconstruction including balloon-test occlusion. The therapeutic decision-making needs a multidisciplinary approach including endovascular, neurosurgical and anesthesiological expertises. The microsurgical treatment needs a step-by-step preoperative planning with anticipation of possible pitfalls and alternative strategies. Classical principles of aneurysm surgery have to be tailored to face the difficulties arising from the size of the sack and from the arterial wall calcifications.

Clipping of previously coiled cerebral aneurysms: efficacy, safety, and predictors in a cohort of 111 patients

OBJECTIVE With the increasing number of aneurysms treated with endovascular coiling, more recurrences are being encountered. The aim of this study was to evaluate the efficacy and safety of microsurgical clipping in the treatment of recurrent, previously coiled cerebral aneurysms and to identify risk factors that can affect the outcomes of this procedure. METHODS One hundred eleven patients with recurrent aneurysms whose lesions were managed by surgical clipping between January 2002 and October 2014 were identified. The rates of aneurysm occlusion, retreatment, complications, and good clinical outcome were retrospectively determined. Univariate and multivariate logistic regressions were performed to identify factors associated with these outcomes. RESULTS The mean patient age was 50.5 years, the mean aneurysm size was 7 mm, and 97.3% of aneurysms were located in the anterior circulation. The mean follow-up was 22 months. Complete aneurysm occlusion, as assessed by intraoperative angiography, was achieved in 97.3% of aneurysms (108 of 111 patients). Among patients, 1.8% (2 of 111 patients) had a recurrence after clipping. Retreatment was required in 4.5% of patients (5 of 111) after clipping. Major complications were observed in 8% of patients and mortality in 2.7%. Ninety percent of patients had a good clinical outcome. Aneurysm size (OR 1.4, 95% CI 1.08-1.7; p = 0.009) and location in the posterior circulation were significantly associated with higher complications. All 3 patients who had coil extraction experienced a postoperative stroke. Aneurysm size (OR 1.2, 95% CI 1.02-1.45; p = 0.025) and higher number of interventions prior to clipping (OR 5.3, 95% CI 1.3-21.4; p = 0.019) were significant predictors of poor outcome. An aneurysm size > 7 mm was a significant predictor of incomplete obliteration and retreatment (p = 0.018). CONCLUSIONS Surgical clipping is safe and effective in treating recurrent, previously coiled cerebral aneurysms. Aneurysm size, location, and number of previous coiling procedures are important factors to consider in the management of these aneurysms.

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.

Safety and efficacy of microsurgical treatment of previously coiled aneurysms: a systematic review and meta-analysis

BACKGROUND

We conducted a systematic review of the literature to evaluate the safety and efficacy of surgical treatment of previously coiled aneurysms.

METHODS

A comprehensive review of the literature for studies on surgical treatment of previously coiled aneurysms was conducted. For each study, the following data were extracted: patient demographics, initial clinical status, location and size of aneurysms, time interval between initial/last endovascular procedure and surgery, surgical indications, and microsurgical technique. We performed subgroup analyses to compare direct clipping versus coil removal and clipping versus parent vessel occlusion, early (<4 weeks post-coiling) versus late surgery and anterior versus posterior circulation.

RESULTS

Twenty-six studies with 466 patients and 471 intracranial aneurysms were included. All of the studies were retrospective and non-comparative case-series. Patients undergoing direct clipping had lower perioperative morbidity (5.0 %, 95 % CI = 2.6-7.4 %) when compared to those undergoing coil removal and clipping (11.1 %, 95 % CI = 5.3-17.0 %) or parent vessel occlusion (13.1 %, 95 % CI = 4.6-21.6 %) (p = 0.05). Patients receiving early surgery (<4 weeks post-coiling) had significantly lower rates of good neurological outcome (77.1 %, 95 % CI = 69.3-84.8 %) when compared to those undergoing late surgery (92.1 %, 95 % CI = 89.0-95.2 %) (p < 0.01). There were higher rates of long-term neurological morbidity in the posterior circulation group (23.1 vs. 4.7 %, p < 0.01) as well as long-term neurological mortality (4.4 vs. 2.8 %, p < 0.01).

CONCLUSIONS

Our meta-analysis suggests that surgical treatment is safe and effective. Our data indicate that aneurysms that are amenable to direct clipping have superior outcomes. Late surgery was also associated with better clinical outcomes. Surgery of recurrent posterior circulation aneurysms was associated with high rates of morbidity and mortality. Given the characteristics of the included studies, the quality of evidence of this meta-analysis is limited.

The combined treatment of stenting and surgery in a giant unruptured aneurysm of the middle cerebral artery

BACKGROUND

This case study reports on a combined therapy of stenting and surgery for a giant unruptured middle cerebral artery (MCA) aneurysm with the aim of preserving the patency of the vessel during surgery.

CASE DESCRIPTION

A 51-year-old male presented with a sudden onset of moderate left hemiparesis and dysarthria. Neuro-radiological evaluations showed a giant right unruptured MCA aneurysm without subarachnoid hemorrhage (SAH). The cerebral angiography confirmed the presence of such an aneurysm producing compression of both M2 branches with consequent slowing of the blood flow. Two weeks later, the patient underwent the positioning of an Enterprise stent and inside this, a flow diverter Silk stent. They were placed across the aneurysm and in one of the two M2 branches with the aim of protecting them during surgical manipulation. The patient went immediately to surgery, where the aneurysm was resected and both M2 branches decompressed.

CONCLUSION

The combined placement of the stents allowed safe and successful surgical dissection of the M2 branches and clipping of the aneurysm without interrupting the blood flow.

Microsurgical Treatment of Previously Coiled Intracranial Aneurysms: Systematic Review of the Literature

OBJECTIVE

To assess indications, complications, clinical outcomes, and technical nuances of microsurgical treatment of previously coiled intracranial aneurysms.

METHODS

A systematic review of the literature was performed using PubMed/MEDLINE and EMBASE databases from January 1990 to December 2013. English-language articles reporting on microsurgical treatment of previously coiled intracranial aneurysms were included. Articles that involved embolization materials other than coils were excluded. Data on aneurysm characteristics, indications for surgery, techniques, complications, angiographic obliteration rates, and clinical outcomes were collected.

RESULTS

The literature review identified 29 articles reporting on microsurgical clipping of 375 previously coiled aneurysms. Of the aneurysms, 68% were small (<10 mm). Indications for clipping included the presence of a neck remnant (48%) and new aneurysmal growth (45%). Rebleeding before clipping was reported in 6% of cases. Coil extraction was performed in 13% of cases. The median time from initial coiling to clipping was 7 months. The angiographic cure rate was 93%, with morbidity and mortality of 9.8% and 3.6%, respectively.

CONCLUSIONS

Microsurgical clipping of previously coiled aneurysms can result in high obliteration rates with relatively low morbidity and mortality in select cases. Considerations for microsurgical strategies include the presence of sufficient aneurysmal tissue for clip placement and the potential need for temporary occlusion or flow arrest. Coil extraction is not needed in most cases.

Recurrent and incompletely treated aneurysms

Endovascular treatment of intracranial aneurysms has become an established technique that can provide stable permanent occlusion in over 85 % of the cases. Even those aneurysms considered untreatable by endovascular means can now often be managed by the use of adjunctive measures, e.g., balloon protection devices, intracranial stents, and semipermeable stents, i.e., "flow diverters." In those cases, in which relevant aneurysm recurrences are documented upon angiographic follow-up, both endovascular and surgical techniques can be employed. In rare cases, combined treatment strategies including parent artery occlusion under bypass protection can be performed. At our center, the majority of relevant aneurysm recurrences after initial coil embolization are managed by a second endovascular procedure. In some cases, e.g., aneurysm recurrences not feasible for endovascular re-treatment, documented aneurysmal growth, bleeding from a previously embolized aneurysm, and acute hemorrhagic or ischemic complications during endovascular procedures, surgical management may be necessary. This report briefly outlines the most frequent treatment scenarios.

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.

[Indications and surgical treatments for failed coiled aneurysms]

The possibility of treating intra-cranial aneurysms (ICA) through an endovascular approach is a great progress. But, as any technique, it has its own limitations. Multidisciplinary neurovascular teams are regularly confronted with ICA where embolization is a poor option or even failed (a residue of more than 5% at six months follow-up or after recanalization). Another potential failure is a coil extrusion into the parent vessel with thrombo-embolic risks. Our team and others in the world developed strategies to manage these complex cases. After a brief review of the literature, we describe our experience and present a modified Gurian classification. This classification allows a better identification of the various failed coiled aneurysms types and their potential surgical treatments.

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.

Management of Residual and Recurrent Aneurysms After Initial Endovascular Treatment

Background:

Coil instability possibly translating into higher delayed rebleeding rates remains a concern in the endovascular management of cerebral aneurysms.

Objective:

To report on 127 patients with endovascular aneurysmal remnants who underwent re-treatment over an 18 year period.

Methods:

Patients presenting with aneurysm residuals &gt;20% of the original lesion, unstable neck remnants, aneurysmal regrowth, or new aneurysmal daughter sacs were treated by an individualized approach, using both endovascular and surgical techniques.

Results:

Seventy-five aneurysmal remnants (59.1%) were treated by further re-embolization. Standard coil embolization was used in 65 cases, stent-protected coiling in 9 cases, and balloon remodeled coiling in 1 case, respectively. Fifty-two (40.9%) aneurysmal remnants were treated surgically. Standard microsurgical clipping was used in 44 patients, parent artery occlusion or trapping under bypass protection in 5 cases, deliberate clipping of the basilar artery trunk in 2 cases, and aneurysm wrapping in one case, respectively. Mechanisms of aneurysm recurrence were coil compaction in 93 cases and regrowth in 34 cases. A single reembolization was sufficient to occlude 78.7% of recurrences from coil compaction, but only 14.3% of recurrences from aneurysm regrowth.

Conclusion:

The individualized approach resulted in complete occlusion of 114 aneurysms (89.7%), with neck remnants and residual aneurysms detectable in 11 (8.7%) and 2 (1.6%) cases, respectively. Treatment morbidity was 11.9%, without significant differences between surgical (15.6%) and endovascular (9.3%) patients (P = .09). Recurrences from coil compaction were safely treated by re-embolization, whereas recurrences from aneurysmal regrowth may best be managed surgically when technically feasible.

Early and late microsurgical clipping for initially coiled intracranial aneurysms

INTRODUCTION

An increasing number of patients with incompletely treated and recurrent intracranial aneurysms are presenting for further management. We review the patients who underwent microsurgical clipping of previously coiled intracranial aneurysms.

METHODS

From 2001 to 2008, we treated 623 aneurysms by endovascular treatment. Among them, 29 patients underwent microsurgical clipping. Nineteen patients (group A) underwent early surgical intervention due to incomplete coiling, a residual neck, coil protrusion, aneurysm rupture, or coil stretching. Ten patients (group B) underwent surgical clipping for recurrent aneurysm and an increased mass effect during the follow-up period. The radiographic images and clinical data were reviewed retrospectively to determine the treatment efficacy, the clinical outcomes, and the factors that are important to select the proper treatment modality.

RESULTS

There were 13 female and 16 male patients. The coils were removed in 6 of the 19 patients in group A and in 1 of the 10 patients in group B. Seventeen (89.5%) of the 19 patients in group A and all the patients (100%) in group B achieved good recovery (Glasgow Outcome Scale 5 and 4) during the clinical follow-up periods (mean 25.2 months).

CONCLUSION

Microsurgical clipping may be chosen as a safe and permanent treatment option for the previously coiled aneurysms with acceptable morbidity in properly selected cases.

Surgical indications and techniques for failed coiled aneurysms

For two decades, endovascular coiling has revolutionized the treatment of intracranial aneurysms. However, as with all techniques, it has limitations and endovascular radiologists and neurosurgeons are regularly confronted by what we call "failed" coiled aneurysms. Failed coiled aneurysms can occur in different situations: a) presence of a significant remnant at the end of an endovascular procedure; b) recanalization of an initially satisfactory occlusion; and c) coil extrusion deemed too thrombogenic or threatening the blood flow in the parent vessel. We and other teams around the world have developed strategies to manage these difficult cases. Here, we compare our own experience with other reports in the literature.

A novel aneurysm clip design for atheromatous, thrombotic, or previously coiled lesions: preliminary experience with the "compression clip" in 6 cases

BACKGROUND

Large and giant lesions often have thicker, atheromatous walls as well as intra-aneurysmal thrombus that combine to prevent traditional clips from closing properly in some cases.

OBJECTIVE

To report the development and use of a novel clip design specifically tailored to treat atheromatous, thrombotic, or previously coiled aneurysms.

METHODS

We retrospectively reviewed the records of 6 patients with complex aneurysms not amenable to simple neck clipping and not considered appropriate for endovascular therapy who were treated using a novel "compression" clip design. We describe the development and use of a novel aneurysm clip design with blades that are not opposed at rest to allow direct clipping of atheromatous, thrombotic, and previously coiled aneurysms.

RESULTS

Four patients had recurrent, previously coiled aneurysms; one of these also had a large thrombotic component. Two patients had complex lesions with heavy atheroma involving a portion of their aneurysms. There were no complications related to the use of the clip, and all patients did well without neurological complications. In every case, the clip allowed straightforward obliteration of the aneurysm without the need for temporary vascular occlusion, aneurysmorrhaphy, or removal of an intra-aneurysmal coil mass. All patients underwent intraoperative angiography to confirm obliteration of the aneurysm with preservation of the normal vasculature.

CONCLUSION

Atheromatous, thrombotic, and previously coiled aneurysms may not be treatable with simple neck clipping and may not be curable with endovascular therapy. For such cases, we designed a novel "compression" clip that has been used safely and successfully in our experience with good short-term follow-up.