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

Microsurgical management of previously embolized intracranial aneurysms: A single center experience and literature review

BACKGROUND

Endovascular treatment of intracranial aneurysms (IAs) provides less invasiveness and lower morbidity than microsurgical clipping, albeit with a long-term recurrence rate estimated at 20%. We present our single-center experience and a literature review concerning surgical clipping of recurrent previously coiled aneurysms.

METHODS

Retrospective analysis of nine (9) patients' data and final clinical/angiographic outcomes, who underwent surgical clipping of IAs in our center following initial endovascular treatment, over a 12-year period (2010-2022). Regarding the literature review, data were extracted from 48 studies including 969 patients with 976 aneurysms.

RESULTS

9 patients (5 males - 4 females) were included in the study with a mean age of 49 years. Subarachnoid hemorrhage was the initial presentation in 78% of patients. Aneurysms' most common location was the middle cerebral artery bifurcation (5/9) followed by the anterior communicating artery (3/9) and the internal carotid artery bifurcation (1/9). Indications for surgery were coil loosening, coil compaction, sac regrowth, and residual neck. Procedure-related morbidity and mortality were zero whereas complete aneurysm occlusion was achieved after surgical clipping in all cases (100%). All patients had minimal symptoms or were asymptomatic (mRS 0-1) at the final follow-up.

CONCLUSIONS

Surgical clipping seems a feasible and safe technique for selected cases of recurrent previously coiled intracranial aneurysms. A universally accepted recurrence classification system and a guideline template for the management of such cases are needed.

Endovascular treatment for anterior inferior cerebellar artery-posterior inferior cerebellar artery (AICA-PICA) common trunk variant aneurysms: Technical note and literature review

The Anterior Inferior Cerebellar Artery-Posterior Inferior Cerebellar Artery (AICA-PICA) common trunk is a rare variant of cerebral posterior circulation in which a single vessel originating from either the basilar or vertebral arteries supplies both cerebellum and brainstem territories. We present the first case of an unruptured right AICA-PICA aneurysm treated with flow diversion using a Shield-enhanced pipeline endovascular device (PED, VANTAGE Embolization Device with Shield Technology, Medtronic, Canada). We expand on this anatomic variant and review the relevant literature. A 39-year-old man presented to our treatment center with vertigo and right hypoacusis. The initial head CT/CTA was negative, but a 4-month follow-up MRI revealed a 9 mm fusiform dissecting aneurysm of the right AICA. The patient underwent a repeat head CTA and cerebral angiogram, which demonstrated the presence of an aneurysm on the proximal portion of an AICA-PICA anatomical variant. This was treated with an endovascular approach that included flow diversion via a PED equipped with Shield Technology. The patient's post-procedure period was uneventful, and he was discharged home after two days with an intact neurological status. The patient is still asymptomatic after a 7-month follow-up, with MR angiogram evidence of stable aneurysm obliteration and no ischemic lesions. Aneurysms of the AICA-PICA common trunk variants have a high morbidity risk due to the importance and extent of the territory vascularized by a single vessel. Endovascular treatment with flow diversion proved to be both safe and effective in obliterating unruptured cases.

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.

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.

Surgical Treatment of Recurrent Previously Coiled and/or Stent-Coiled Intracerebral Aneurysms: A Single-Center Experience in a Series of 75 Patients

BACKGROUND

Endovascular treated cerebral aneurysms have a greater recurrence rate compared with microsurgical clip ligation. Despite recent endovascular advances, microsurgical clip ligation might be the treatment of choice for certain previously endovascular treated recurrent aneurysms. We report on our single-center experience with 76 previously coiled and/or stent-coiled aneurysms.

OBJECTIVE

To analyze the surgical and radiologic outcome after clipping of previous endovascular treated recurrent cerebral aneurysms.

METHODS

Patients were retrospectively identified. Demographic data, aneurysm size, location, perioperative coil extraction, occlusion rate, and complication rate were recorded. Patients were divided into a previously coiled-only group (COG) and a previously stent-assisted coiled group (SAC).

RESULTS

Seventy-five patients with 76 aneurysms were included. Sixty-nine patients were included in the COG, 7 patients in the SAC group. Complete or acceptable near-complete occlusion was obtained in 95% of patients in the COG and 57% in the SAC group. Two patients in the COG (2.9%) died postoperatively of a major stroke. One patient died of rehemorrhage after wrapping of an aneurysm. Minor complications occurred in 8.7%. In the SAC group, the mortality was 0%, with 1 major stroke (14.2%), 1 minor stroke (14.2%), and 1 cranial nerve palsy (14.2%). Intraoperative coil extraction and previous stent-assisted coiling were significant predictors of complication rate (P = 0.025 and P = 0.0036 respectively). Previous stent-assisted coiling was a significant predictor of incomplete occlusion (P = 0.036).

CONCLUSIONS

Microsurgical clipping of previously endovascular treated recurrent aneurysms is an effective treatment with high obliteration rates. Previously stent-assisted coiling and intraoperative coil extraction are predictors of worse outcome and incomplete occlusion.

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.

Outcomes of Microsurgical Clipping of Recurrent Aneurysms After Endovascular Coiling

BACKGROUND

The outcomes of microsurgery of previously coiled aneurysms have been poorly described, and little is known about the factors predictive of poor outcome. Here we aimed to identify predictors of poor outcome following microsurgery for previously coiled recurrent aneurysms.

METHODS

In this retrospective cohort study of a prospectively maintained vascular database, we reviewed presentations, recurrent aneurysm measurements, surgery, and outcomes of microsurgical clipping of recurrent previously coiled intracranial aneurysms.

RESULTS

Our series comprised 39 patients (mean age, 49 years; range, 22-70 years) who underwent microsurgical clipping of 40 previously coiled intracranial aneurysms. One patient suffered seizures, 1 patient experienced transient neurologic worsening, and 1 patient developed hyponatraemia, none of whom had long-term sequelae. Two patients sustained postoperative infarcts, for an overall incidence of permanent morbidity of 5.1%. There were no deaths or rebleeds on follow-up. In 3 patients, including the 2 patients with infarct and 1 patient with a transient deficit, an attempt was made to remove the coil ball. These patients had larger aneurysms (1106 mm³ vs. 135 mm³; P = 0.005), with larger coil balls (257 mm³ vs. 52 mm³; P = 0.01) and wider necks (7.09 mm vs. 2.69 mm; P = 0.02) but smaller remnant heights (1.59 mm vs. 1.99 mm; P = 0.04). They were also more likely to have prolapsing coil loops (3/3 vs. 3/27; P = 0.016).

CONCLUSIONS

Our study demonstrates good clinical outcomes from microsurgical clipping of recurrent aneurysms. In the vast majority of cases, clips can be applied primarily. Coil ball removal is associated with increased morbidity, and thus should be considered only as a second-line option, with the likely need identified before the initiation of surgery.

Endoscopic Endonasal Transclival Approach versus Dual Transorbital Port Technique for Clip Application to the Posterior Circulation: A Cadaveric Anatomical and Cerebral Circulation Simulation Study

Purpose  Simulation training offers a useful opportunity to appreciate vascular anatomy and develop the technical expertise required to clip intracranial aneurysms of the posterior circulation. Materials and Methods  In cadavers, a comparison was made between the endoscopic transclival approach (ETA) alone and a combined multiportal approach using the ETA and a transorbital precaruncular approach (TOPA) to evaluate degrees of freedom, angles of visualization, and ergonomics of aneurysm clip application to the posterior circulation depending on basilar apex position relative to the posterior clinoids. Results  ETA alone provided improved access to the posterior circulation when the basilar apex was high riding compared with the posterior clinoids. ETA + TOPA provided a significantly improved functional working area for instruments and visualization of the posterior circulation for a midlevel basilar apex. A single-shaft clip applier provided improved visualization and space for instruments. Proximal and distal vascular control and feasibility of aneurysmal clipping were demonstrated. Conclusions  TOPA is a medial orbital approach to the central skull base; a transorbital neuroendoscopic surgery approach. This anatomical simulation provides surgical teams an alternative to the ETA approach alone to address posterior circulation aneurysms, and a means to preoperatively prepare for intraoperative anatomical and surgical instrumentation challenges.

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.

Aneurysm in the anterior inferior cerebellar artery-posterior inferior cerebellar artery variant: Case report and review of literature

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We reported a case of an aneurysm in the AICA-PICA variant which was subsequently excised.

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Considerable variation exists in the anatomy of the vertebrobasilar system.

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Understanding the variations and the aneurysms that may arise from them is an important aspect of neurosurgical practice.

Introduction

There are variations in the anatomy of the vertebrobasilar system amongst which the Anterior Inferior Cerebellar Artery-Posterior Inferior Cerebellar Artery (AICA-PICA) variant is thought to have a prevalence of 20–24% (based on retrospective studies). Despite this, aneurysms of the AICA-PICA variant are rare. We present a case of an AICA-PICA aneurysm and discuss its presentation and management, along with a review of literature.

Presentation of case

We describe the case of a 35 year old female who presented with signs of meningismus. On the basis of radiological imaging it was initially misdiagnosed as a thrombosed arteriovenous malformation (AVM). The patient was eventually discharged with a plan of interval imaging and interventional radiology (if required). The patient presented again with similar signs and symptoms. Re-evaluation of imaging revealed an aneurysm of the AICA-PICA variant which was managed surgically.

Discussion

Aneurysms of the AICA-PICA variant are rare. The radiological features and surgical management represent a unique clinical entity and are discussed below.

Conclusion

The prevalence of the AICA-PICA variant might be high but aneurysms in this vessel are rare. The scant knowledge available on this subject makes it a diagnostic difficulty.