The role of endovascular treatment for ruptured distal anterior cerebral artery aneurysms: comparison with microsurgical clipping

Current state of endovascular treatment of anterior cerebral artery aneurysms

The locations of anterior cerebral artery (ACA) aneurysms vary, and various aneurysms can occur along the course of the ACA. Ruptured and some unruptured ACA aneurysms may require aggressive treatment to avoid bleeding or rebleeding. Although open surgery is an effective treatment for ACA aneurysms, endovascular treatment (EVT) is becoming an alternative treatment in select cases. EVT techniques for ACA aneurysms often vary and are performed on a case-by-case basis according to the nature and location of the aneurysm. To better understand the EVT strategy for ACA aneurysms, it is necessary to review EVT for ACA aneurysms. In this review, the following topics are discussed: ACA anatomy and anomalies, classifications of ACA aneurysms, the natural history of ACA aneurysms, open surgery and EVT statuses for ACA aneurysms, EVT techniques for various ACA aneurysms, and the prognosis and complications of EVT for ACA aneurysms. According to our review and experience, traditional coiling EVT is still the preferred therapy for most ACA aneurysms. For A1 aneurysms, EVT is challenging. After the selection of appropriate cases, deployment of a flow diverter and Woven EndoBridge device can result in a good prognosis for patients with ACA aneurysms. In addition, parent artery occlusion can be used to treat A1 aneurysms with good collateral circulation and some distal ACA aneurysms. In general, EVT is gaining popularity as an alternative treatment option for ACA aneurysms.

Risk Factors for the Recurrence of Distal Anterior Cerebral Artery Aneurysms After Endovascular Treatment

OBJECTIVE

We aimed to investigate risk factors for the recurrence of distal anterior cerebral artery (DACA) aneurysms after endovascular treatment (EVT).

METHODS

The clinical and radiologic outcomes of DACA aneurysms treated with endovascular methods at a single tertiary hospital from September 2008 to December 2021 were retrospectively reviewed. We measured the angle between 2 distal branches of DACA aneurysms and categorized the angle as follows: 1) wide-angle (≥180°), and 2) narrow-angle type configuration (<180°). Univariate and multivariate analyses were performed to demonstrate the relationships between characteristics of DACA aneurysm and recurrence risk.

RESULTS

In total, 132 DACA aneurysms were treated in our institution. Among these, 47 DACA aneurysms after EVT were included in this study. Forty patients underwent coil embolization without stent, 7 for stent-assisted coil embolization. At the last follow-up (mean 30.2 ± 24.2 months), overall recurrence rate was 23.4% (n = 11). Recurrence rate of the wide-angle type (9 of 23, 39.1%) was significantly greater than narrow-angle type (2 of 24, 8.3%) (P = 0.041; odds ratio 8.174, 95% confidence interval 1.094-61.066). Irregular shape of the DACA aneurysm also showed significantly greater recurrence rate (P = 0.011; odds ratio 10.663, 95% confidence interval 1.701-66.838) after endovascular treatment.

CONCLUSIONS

The wide-angle between 2 distal branches of DACA aneurysm and irregular shape might be independent risk factors for the recurrence after endovascular treatment for DACA aneurysms.

Rupture Risk Factors and Strategies for Unruptured Distal Anterior Cerebral Artery Aneurysms

BACKGROUND

Distal anterior cerebral artery (dACA) aneurysms are rare. Ruptured dACA aneurysms typically present with subarachnoid hemorrhage in conjunction with intracerebral hematoma and cause neurological deterioration. This study aimed to determine their risk of rupture and examine associated factors.

METHODS

We retrospectively analyzed patients with dACA aneurysms to compare patient and aneurysm characteristics between ruptured and unruptured aneurysms. Clinical outcome was used the modified Rankin scale. Univariate analyses were performed to identify rupture risk factors.

RESULTS

One hundred three patients with dACA aneurysms were examined (51 ruptured and 52 unruptured). The median aspect ratio of ruptured and unruptured aneurysms was 1.69 and 1.22, respectively (P < 0.01). The median maximum diameter of ruptured and unruptured aneurysms was 5.2 and 3.1 mm, respectively (P < 0.01). The median size ratio of ruptured and unruptured aneurysms was 3.32 and 2.17, respectively (P < 0.01). Maximum diameter was <5 mm in 45.2% of ruptured dACA aneurysms. dACA aneurysm, showing size ratio >2.4 and aspect ratio >1.4, had ruptured in 71.4% and 78.6%, respectively. We suggested that these are the threshold of size ratio and aspect ratio for rupture of dACA aneurysms. A total percentatge of 78.1% of aneurysms with aspect ratio >1.4 and size ratio >2.4 had ruptured.

CONCLUSIONS

Distal anterior cerebral artery (dACA) aneurysms may rupture, even when small. We found a significant difference between ruptured and unruptured aneurysms with respect to maximum diameter, aspect ratio, and size ratio. Treatment for small aneurysms should be considered based on size ratio and aspect ratio, not just size.

Neurosurgical clipping versus endovascular coiling for patients with ruptured anterior circulation aneurysms: A systematic review and meta-analysis

To compare the safety and efficacy of clipping and coiling in patients with ruptured anterior circulation aneurysms. A systematic search of four databases (PubMed, Web of Science, Cochrane Library, and Embase) was conducted to identify comparative articles on endovascular coiling and surgical clipping in patients with ruptured anterior circulation aneurysms. Meta-analyses were conducted using random-effects models. Nineteen studies, including 1983 patients, were included. The meta-analysis showed that neurosurgical clipping was associated with a lower incidence of retreatment (OR:0.28, 95% CI (0.11, 0.70), P = 0.006) than endovascular coiling, which seemed to be a result of incomplete occlusion (OR:0.22, 95% CI (0.11, 0.45), P < 0.001). Neurosurgical clipping was associated with lower mortality (OR:0.45, 95% CI (0.25, 0.82), P = 0.009) at short-term follow-up than endovascular coiling. However, neurosurgical clipping showed a higher incidence of ischemic infarction (OR:2.28, 95% CI (1.44, 3.63), P < 0.001) and a longer length of stay (LOS) (WMD:6.12, 95% CI (4.19, 8.04), P < 0.001) after surgery than endovascular coiling. Furthermore, the pooled results showed no statistically significant differences between the two groups regarding poor outcome, long-term mortality, rebleeding, vasospasm, and hydrocephalus. Evidence from this systematic review illustrates that neurosurgical clipping may be superior to endovascular coiling for ruptured anterior circulation aneurysms. Large-scale RCTs should be conducted to verify these outcomes and provide results according to patient status.

Coil embolization for ruptured distal anterior cerebral artery aneurysm at the supracallosal portion: Two case reports

Background

Distal anterior cerebral artery (ACA) aneurysms occur more frequently in the genu portion and much less frequently in the supracallosal portion (A4-A5). This report describes two cases of ruptured cerebral aneurysms occurring at the supracallosal portion successfully treated with coil embolization.

Case Description

Case 1 involved a 61-year-old female with sudden-onset headache and vomiting attributed to subarachnoid hemorrhage (SAH). Digital subtraction angiography (DSA) revealed a bihemispheric ACA and aneurysm in the supracallosal portion. Coil embolization was performed, and the patient was discharged without neurological deficit. Case 2 involved a 35-year-old man with severe headache and disturbance of consciousness caused by SAH. DSA showed an aneurysm in A4 of the accessory ACA, and coil embolization was performed. After rehabilitation, he was discharged with a modified Rankin scale score of 2.

Conclusion

Coil embolization for a ruptured aneurysm at the supracallosal portion can yield good results if the patient is appropriately selected.

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.

Current treatment options and prognostic factors for ruptured distal anterior cerebral artery aneurysms

Background:

Distal anterior cerebral artery (ACA) aneurysms are rare, representing 1–9% of all intracranial aneurysms. The best treatment strategy for these aneurysms continues to be debated. We clarified the clinical features and treatment outcomes of patients with ruptured distal ACA aneurysms according to the treatment options at our institute.

Methods:

Thirty-seven consecutive patients (26 women; mean age, 65.2 years) with ruptured distal ACA aneurysms who underwent surgical clipping or coil embolization between 2012 and 2018 were included in the study. Clinical presentations, radiographic findings, and outcomes were retrospectively reviewed and compared between patients who underwent either surgical clipping or coil embolization. Risk factors associated with poor outcomes (modified Rankin Scale 4–6) were analyzed using multiple regression analysis.

Results:

Nineteen patients (51.4%) had World Federation Neurological Surgeons (WFNS) Grade IV-V, 18 (48.7%) had frontal lobe hematomas, and 13 (35.1%) had multiple aneurysms. Surgical clipping and endovascular coiling were performed in 28 (75.7%) and nine (24.3%) patients, respectively. Aneurysms located at the A4-5 portions were mainly treated by surgical clipping (P = 0.04). There were no significant between-group differences in procedure-related morbidity and mortality; however, the complete occlusion rate was higher in the surgical group (P < 0.01). Overall, a favorable neurological outcome at discharge (mRS 0–3) was obtained in 23 patients (62.5%). Multiple regression analysis revealed that WFNS Grade IV-V and frontal lobe hematomas were risk factors for poor outcomes (mRS 4–6).

Conclusion:

Acceptable outcomes were obtained in 62.5% of cases, and there were no significant between-group differences in treatment results between clipping and coiling. A poor WFNS grade and intracerebral hematomas were risk factors for a poor prognosis.

Endovascular Coiling Versus Neurosurgical Clipping for Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Meta-analysis

Background Aneurysmal subarachnoid hemorrhage is a frequently devastating condition with a reported incidence of between 10 and 15 people per 100,000 in the United States. Currently, according to the best of our knowledge, there are not enough meta-analyses available in the medical literature of the last five years which compare the risks and benefits of endovascular coiling with neurosurgical clipping. Methods Twenty-two studies were selected out of the short-listed studies. The studies were selected on the basis of relevance to the topic, sample size, sampling technique, and randomization. Data were analyzed on Revman software. Results Mortality was found to be significantly higher in the endovascular coiling group (odds ratio (OR): 1.17; confidence interval (CI): 95%, 1.04, 1.32). Re-bleeding was significantly higher in endovascular coiling (OR: 2.87; CI: 95%, 1.67, 4.93). Post-procedure complications were significantly higher in neurosurgical clipping compared to endovascular coiling (OR: 0.36; CI: 95%, 0.24, 0.56). Neurosurgical clipping was a 3.82 times better surgical technique in terms of re-bleeding (Z = 3.82, p = 0.0001). Neurosurgical clipping is a better technique requiring fewer re-treatments compared to endovascular coiling (OR: 4.64; CI: 95%, 2.31, 9.29). Endovascular coiling was found to be a better technique as it requires less rehabilitation compared to neurosurgical clipping (OR: 0.75; CI: 95%, 0.64,0.87). Conclusion Neurosurgical clipping provides better results in terms of mortality, re-bleeding, and re-treatments. Endovascular coiling is a better surgical technique in terms of post-operative complications, favorable outcomes, and rehabilitation.

Kissing aneurysms of the distal anterior cerebral artery: A case report and literature review

Intracranial 'kissing' aneurysms are rare types of multiple aneurysms referring to two adjacent aneurysms arising from identical or different arteries with separate origins and partially adherent walls. The present study reported a 54-year-old female patient, who was identified with a 'kissing' aneurysm in the A3 segment of the bilateral anterior cerebral arteries, as demonstrated by head computed tomography and emergency cerebral digital subtraction angiography analysis. In total, 12 days following the clipping of the aneurysms, the patient was discharged with a Modified Rankin Scale=0 and recovered well with no neurological deficits. Based on previous literature, it was indicated that the majority of patients with 'kissing' aneurysm have a good prognosis and the cure rate is as high as 96.8%. However, the recovery rate may not be that high as the sample size is not large enough to thoroughly demonstrate the complete prognosis of 'kissing' aneurysms.

Endovascular Management of Ruptured Distal Anterior Cerebral Artery (DACA) Aneurysms: A Retrospective Review Study

OBJECTIVE

Distal anterior cerebral artery (DACA) aneurysms are rare, and their treatment by either surgical clipping or endovascular treatment poses technical difficulties. Earlier studies have reported higher complication rates in DACA aneurysms compared with other aneurysms in the circle of Willis. Therefore, endovascular management of DACA aneurysms still remains a challenge. The aim of this report is to review clinical presentation, angiographic presentation of DACA aneurysms, complications, and outcome of their endovascular treatment in our institutional experience.

METHODS

A retrospective review of 186 patients with intracranial aneurysms treated with endovascular management from September 2009 to December 2013 in the Max Superspecialty Hospital, New Delhi, India, 11 patients (5.9%) with 12 DACA aneurysms were studied retrospectively. We report the clinical presentations, cerebral angiographic findings, endovascular treatment, complications, and outcomes. The clinical and angiographic outcomes were assessed using modified Rankin scales and the Raymond scale, respectively.

RESULTS

Of 11 patients, 54.5% were female and 45.5% were male; the mean age was 48.4 years (range, 33-65 years). All patients had subarachnoid hemorrhage that indicated ruptured DACA aneurysm. All the DACA aneurysms were small. Postcoiling angiograms showed complete occlusion in 9 patients. Two patients had intraprocedural aneurysm rupture but without any clinical sequelae, and 1 patient had thrombus formation, which was thrombolysed at the end of coiling. All patients had good outcomes.

CONCLUSIONS

Our experience with 11 patients showed that endovascular management of small DACA aneurysms, though associated with higher intraprocedural events, is associated with good outcome.

Clipping Versus Coiling in Anterior Circulation Ruptured Intracranial Aneurysms: A Meta-Analysis

OBJECTIVE

To evaluate open surgical versus endovascular repair of anterior circulation ruptured intracranial aneurysms based on operative mortality, permanent neurologic deficit, late mortality, and need for reintervention.

METHODS

This meta-analysis included articles published since December 6, 2016, that compared outcomes of the 2 methods. Extracted data were organized in a standard table format, including first author, country, covered study period, publication year, number of patients and patients at follow-up, operative mortality rate (with 30 days from treatment), permanent neurologic deficit (appearing after surgery), late mortality (after 1 month), and reintervention (surgery or coiling) for both groups of patients. Follow-up was at least 1 year.

RESULTS

There were 8 articles that matched our study criteria. The study population was 628 patients; 374 were treated with surgical clipping, and 254 were treated with endovascular coiling. Pooled results showed no statistically significant difference between the 2 groups in terms of operative mortality, permanent neurologic deficit, late mortality, and need for reintervention.

CONCLUSIONS

Selection of the appropriate procedure must be made on the basis of the special characteristics of each case.

Safety and Efficacy of Surgical and Endovascular Treatment for Distal Anterior Cerebral Artery Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND

Aneurysms of the distal anterior cerebral artery (DACA) are rare, representing between 1% and 9% of all intracranial aneurysms. The best treatment strategy for these aneurysms continues to be debated.

OBJECTIVE

We conducted a systematic review of the literature to evaluate the safety and efficacy of treatment strategies of DACA aneurysms.

METHODS

A systematic search of Medline, Embase, Scopus, and Web of Science was performed for studies published from January 2000 to August 2015. We included studies describing treatment of DACA aneurysms with ≥10 patients. Random effects meta-analysis was used to pool the following outcomes: complete occlusion, technical success, periprocedural morbidity/mortality and stroke rates, aneurysm recurrence/rebleed, and long-term neurologic morbidity/mortality.

RESULTS

Thirty studies with 1329 DACA aneurysms were included. Complete occlusion was 95% (95% confidence interval [CI], 91.0%-97.0%) in the surgical group and 68% (95% CI, 56.0%-78.0%) in the endovascular group (P < 0.0001). Aneurysm recurrence occurred in 3% (95% CI, 2.0%-4.0%) after surgery and in 19.1% (95% CI, 12.0%-27.0%) after endovascular treatment (P < 0.0001). Overall neurologic morbidity and mortality were 15% (95% CI, 11.0%-21.0%) and 9% (95% CI, 7.0%-11.0%) after surgery and 14% (95% CI, 10.0%-19.0%) (P = 0.725) and 7% (95% CI, 5.0%-10.0%) (P = 0.422) after endovascular treatment, respectively. Overall long-term favorable neurologic outcome was 80% and it was equal in both groups (80%; 95% CI, 73.0%-85.0% in the surgical group and 80%; 95% CI, 72.0%-87.0% in the endovascular group) (P = 0.892).

CONCLUSIONS

Our meta-analysis showed that both treatment modalities are technically feasible and effective with sufficient long-term aneurysm occlusion and acceptable recurrence/rebleed rates. Surgical treatment is associated with superior angiographic outcomes. There were no substantial differences in procedure-related morbidity and mortality. These findings are important because they suggest that therapy of DACA aneurysms should be performed on a selective, case-by-case basis to maximize patient benefits.

Coiling Is Not Superior to Clipping in Patients with High-Grade Aneurysmal Subarachnoid Hemorrhage: Systematic Review and Meta-Analysis

BACKGROUND

Outcomes of coiling embolization versus clipping for patients with high-grade aneurysmal subarachnoid hemorrhage (aSAH) have not been previously compared. We reviewed current evidence regarding the safety and efficacy of clipping versus coiling for high-grade aSAH.

METHODS

We conducted a meta-analysis of studies that compared clipping with coiling in patients with high-grade aSAH published from January 1999 to February 2016 in Medline, Embase, and Cochrane databases based on PRISMA inclusion and exclusion criteria. Binary outcome comparisons between clipping and coiling were described using odds ratios (ORs).

RESULTS

Three randomized controlled trials (RCTs) and 16 observational studies were included. There was no statistical difference in good outcome rates between the clipping and coiling groups (OR, 1.44; 95% confidence interval [CI], 0.97-2.13). Subgroup analysis showed no significant difference between the 2 treatments in non-RCTs (OR, 1.49; 95% CI, 0.95-2.36) and RCTs (OR, 1.15; 95% CI, 0.59-2.25). Coiling was associated with higher mortality (OR, 0.55; 95% CI, 0.41-0.75). Lower mortality was associated with clipping in non-RCTs (OR, 0.54; 95% CI, 0.40-0.74), but there was no difference in the RCTs (OR, 0.79; 95% CI, 0.19-3.39). Coiling was not associated with lower rates of complications including rebleeding (OR, 0.62; 95% CI, 0.30-1.29), ischemic infarct (OR, 0.89; 95% CI, 0.53-1.49), symptomatic vasospasm (OR, 0.76; 95% CI, 0.45-1.29), or shunt-dependent hydrocephalus (OR, 1.33; 95% CI, 0.52-3.40).

CONCLUSION

The outcome with coiling is not superior to clipping in patients with high-grade aSAH; moreover, coiling has a greater risk of mortality.

Endovascular Treatment of Ruptured Pericallosal Artery Aneurysms

Objective

Aneurysms arising from the pericallosal artery (PA) are uncommon and challenging to treat. The aim of this study was to report our experiences of the endovascular treatment of ruptured PA aneurysms.

Methods

From September 2003 to December 2013, 30 ruptured PA aneurysms in 30 patients were treated at our institution via an endovascular approach. Procedural data, clinical and angiographic results were retrospectively reviewed.

Results

Regarding immediate angiographic control, complete occlusion was achieved in 21 (70.0%) patients and near-complete occlusion in 9 (30.0%). Eight procedure-related complications occurred, including intraprocedural rupture and early rebleeding in three each, and thromboembolic event in two. At last follow-up, 18 patients were independent with a modified Rankin Scale (mRS) score of 0-2, and the other 12 were either dependent or had expired (mRS score, 3-6). Adjacent hematoma was found to be associated with an increased risk of poor clinical outcome. Seventeen of 23 surviving patients underwent follow-up conventional angiography (mean, 16.5 months). Results showed stable occlusion in 14 (82.4%), minor recanalization in two (11.8%), and major recanalization, which required recoiling, in one (5.9%).

Conclusion

Our experiences demonstrate that endovascular treatment for a ruptured PA aneurysms is both feasible and effective. However, periprocedural rebleedings were found to occur far more often (20.0%) than is generally suspected and to be associated with preoperative contrast retention. Analysis showed existing adjacent hematoma is predictive of a poor clinical outcome.