Clipping vs Coiling for Brain Aneurysm

(MCAAT Trial)

Overseen By Sudeshna Bhattacharyna

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Alberta

Disqualifiers: Contrast allergy, AVM, Consent issues, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

Duration: Immediate procedure

400 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to compare two treatments for brain aneurysms located on the middle cerebral artery (MCA). It will examine surgical clipping, which involves placing a clip on the aneurysm, and endovascular methods, which use devices like stents to manage the aneurysm from inside the blood vessel. The goal is to determine which treatment works best for these specific aneurysms. Individuals with a documented aneurysm on the MCA who are suitable for either treatment approach might be a good fit for this trial. As an unphased trial, this study offers participants the opportunity to contribute to important research that could enhance treatment options for future patients.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. Please consult with the trial coordinators for more details.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research has shown that both endovascular and surgical treatments for brain aneurysms have been studied for safety. For endovascular treatments, one study found a 12% chance of complications, including a 2.4% chance of the aneurysm bursting and an 8.5% chance of blood flow blockage. Another study found that the risk of dying in the hospital was 5% or less for aneurysms that hadn't burst.

Surgical treatment, particularly microsurgical clipping, has proven to be quite safe. Specifically, one study reported that almost 98% of patients had good brain function two years after surgery, indicating that most people did well after their operations.

Both treatments carry risks, but they are generally considered safe options for treating brain aneurysms. Discussing with a doctor is crucial to determine which treatment might be best based on individual health needs. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the treatments for brain aneurysms in this trial because they offer two distinct approaches: endovascular management and surgical management. Endovascular management, often referred to as "coiling," involves a minimally invasive technique where coils are inserted into the aneurysm via a catheter to prevent it from rupturing. This approach is less invasive than traditional surgery and can lead to quicker recovery times. On the other hand, surgical management, known as "clipping," involves opening the skull to place a clip around the aneurysm, which can provide a more permanent solution. By comparing these two methods, researchers aim to determine which is more effective and safer for patients, potentially leading to better treatment strategies for brain aneurysms.

What evidence suggests that this trial's treatments could be effective for brain aneurysms?

This trial will compare surgical management, such as clipping, with endovascular management for treating brain aneurysms. Research has shown that surgery, like clipping, is often more effective for treating unruptured brain aneurysms. One study found that 97.98% of patients maintained good brain function two years after surgery. Another study found that surgical clipping surpassed endovascular treatments, like coiling, in preventing aneurysm complications. However, endovascular treatments can significantly reduce the risk of rupture, especially in larger aneurysms. While both methods offer benefits, evidence suggests that surgical clipping may provide better results for certain aneurysms. ^{1 2 6 7 8}

Who Is on the Research Team?

Tim Darsaut

Principal Investigator

University of Alberta Faculty of Medicine and Dentistry

Are You a Good Fit for This Trial?

This trial is for adults with a brain aneurysm located on the middle cerebral artery, which can be treated by surgery or endovascular methods. It includes those with recent or older ruptures (over 30 days old) who are in stable condition (WFNS grade 4 or less). People allergic to contrast material, unable to consent, with AVM-related aneurysms, or severe ruptures (WFNS grade 5) cannot join.

Inclusion Criteria

My SAH condition is not the most severe.

I have at least one aneurysm in my brain's MCA vessel, whether it has burst or not.

My team considers me fit for surgery or a less invasive procedure for my aneurysm.

Exclusion Criteria

I am unable to give consent myself.

I have an aneurysm linked to my AVM condition.

I cannot receive contrast material due to severe allergies or reactions.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo either surgical clipping or endovascular management of MCA aneurysms

Immediate procedure

Follow-up

Participants are monitored for treatment success and safety, including assessments for intracranial hemorrhage and residual aneurysm

5 years

Annual visits for imaging and assessments

Long-term follow-up

Continued monitoring for overall mortality and morbidity

5 years

What Are the Treatments Tested in This Trial?

Interventions

• Endovascular management
• Surgical management

Trial Overview The study compares surgical clipping versus endovascular treatment for MCA aneurysms. Surgical clipping might be preferred due to easier access and control during rupture. Endovascular options include stents and flow disruptors but face challenges like wide necks of the aneurysm.

How Is the Trial Designed?

Group I: Surgical management Active Control 1 Intervention

Group II: Endovascular management Active Control 1 Intervention

Who Is Running the Clinical Trial?

University of Alberta

Lead Sponsor

Trials

957

Recruited

437,000+

Published Research Related to This Trial

In a study of 48 patients with intracranial aneurysms, those treated with endovascular coiling had a better initial functional status (lower modified Rankin Scale score) compared to those who underwent surgical clipping, indicating a potentially safer option at the time of treatment.

At the one-year follow-up, the endovascular coiling group showed significant improvement in functional outcomes, while the surgical clipping group did not, suggesting that coiling may offer better long-term benefits, although no significant difference was found between the two groups overall.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparison of endovascular coiling and surgical clipping for the treatment of intracranial aneurysms: A prospective study. Taheri, Z., Harirchian, MH., Ghanaati, H., et al.[2020]

In a review of 24 studies involving 31,865 patients, endovascular coiling was found to result in significantly lower disability and complications compared to neurosurgical clipping for treating unruptured intracranial aneurysms.

Clipping was associated with higher rates of short-term disability and complications, indicating that coiling may be the safer and more effective option for patients in the immediate aftermath of treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Endovascular coiling versus neurosurgical clipping in patients with unruptured intracranial aneurysm: a systematic review. Hwang, JS., Hyun, MK., Lee, HJ., et al.[2021]

In a study of 30 patients treated with endovascular coil embolization for middle cerebral artery (MCA) aneurysms, complete obliteration was achieved in 93% of cases, showing that coiling can be as effective as surgical clipping, which had a similar success rate of 92%.

Coiling is particularly beneficial for patients with short M1 arteries or serious medical conditions, as it presents a lower risk of complications compared to clipping, with only 6.7% experiencing post-procedural infarctions and fewer severe complications overall.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Endovascular coiling of middle cerebral artery aneurysms as an alternative to surgical clipping. Kim, KH., Cha, KC., Kim, JS., et al.[2013]

In a study of 140 patients with anterior circulation aneurysms, endovascular coiling resulted in a more favorable neurological outcome at one year, with 80% of patients achieving a good outcome compared to 68.6% in the clipping group.

Coiling was associated with a lower mortality rate (1.4%) compared to clipping (4.3%), suggesting that coiling may be a safer and less invasive option for treating these aneurysms.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Aneurysmal Subarachnoid Hemorrhage: Outcome of Aneurysm Clipping Versus Coiling in Anterior Circulation Aneurysm. Wadd, IH., Haroon, A., Habibullah, ., et al.[2016]

Endovascular coiling is now the preferred treatment for ruptured intracranial aneurysms, showing benefits over surgical clipping according to the ISAT study, which is a multicenter randomized controlled trial.

The optimal management for unruptured intracranial aneurysms is still uncertain, as no randomized controlled trials have compared conservative management with surgical clipping or endovascular coiling; an ongoing trial aims to clarify whether active treatment improves outcomes compared to observation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Current update on the randomized controlled trials of intracranial aneurysms. Yoon, W.[2021]

In a study of 179 severe subarachnoid hemorrhage (SAH) cases, direct microsurgical clipping resulted in a more favorable outcome (69.16% good recovery or moderate disability) compared to endovascular coiling (44.06%).

The choice between clipping and coiling is guided by specific clinical criteria, with clipping preferred for younger patients and those with more severe conditions, indicating its effectiveness in acute severe SAH cases.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of clipping and coiling in acute severe subarachnoid hemorrhage after international subarachnoid aneurysmal trial (ISAT) results. Kato, Y., Sano, H., Dong, PT., et al.[2005]

Endovascular coiling is currently preferred over microsurgical clipping for treating unruptured intracranial aneurysms (UIA) due to its lower associated risks of complications like cerebrospinal fluid leakage and infection, as well as reduced mortality and disability rates.

This study aims to provide a direct comparison of the long-term safety and efficacy of endovascular coiling versus surgical clipping in a randomized controlled trial, assessing outcomes such as disability and recurrence rates over 6 months and 1 year.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

To clip or to coil for unruptured intracranial aneurysm?: A protocol of randomized controlled trial. Huang, X., Yan, G., Qin, Z., et al.[2021]

In a study of 291 patients with unruptured intracranial aneurysms, surgical clipping was found to be more effective than endovascular treatment, with a lower incidence of treatment failure (9% vs. 19%) at one year.

While clipping showed better efficacy, it was associated with higher rates of neurologic deficits and longer hospital stays compared to endovascular treatment, indicating a trade-off between effectiveness and safety.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Pragmatic Randomized Trial Comparing Surgical Clipping and Endovascular Treatment of Unruptured Intracranial Aneurysms. Darsaut, TE., Findlay, JM., Bojanowski, MW., et al.[2023]

In a study of 412 aneurysms treated with microsurgical clipping, 94.01% of unruptured aneurysms and 75.4% of ruptured aneurysms achieved favorable outcomes, indicating that this method is effective for both types of aneurysms.

Factors such as older age, higher baseline mRS scores, and posterior circulation location were linked to worse outcomes, suggesting that patient characteristics can influence the success of the procedure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Make Clipping Great Again: Microsurgery for Cerebral Aneurysms by Dual-Trained Neurosurgeons. Munich, SA., Vakharia, K., McPheeters, MJ., et al.[2020]

Surgical clipping is associated with lower mortality and reduced risk of rebleeding for patients with ruptured intracranial aneurysms (IAs), suggesting it may be the preferred treatment for these cases.

In contrast, clipping leads to a higher incidence of poor outcomes and bleeding for unruptured IAs compared to endovascular coiling, indicating that coiling may be safer for these patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Neurosurgical Clipping versus Endovascular Coiling for Patients with Intracranial Aneurysms: A Systematic Review and Meta-Analysis. Jiang, Z., Chen, Y., Zeng, C., et al.[2020]

In a study of 366 patients with poor-grade ruptured aneurysms, endovascular coiling showed a higher unadjusted rate of favorable outcomes at 6 and 12 months compared to surgical clipping, but this difference was not statistically significant after adjusting for other factors.

Patients treated with endovascular coiling had a significantly higher risk of developing radiologic hydrocephalus compared to those treated with clipping, indicating a potential safety concern with the coiling method.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Endovascular Coiling versus Surgical Clipping for Poor-Grade Ruptured Intracranial Aneurysms: Postoperative Complications and Clinical Outcome in a Multicenter Poor-Grade Aneurysm Study. Zhao, B., Tan, X., Yang, H., et al.[2021]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10474558/

Outcomes Associated With Intracranial Aneurysm Treatments ... Outcomes associated with intracranial aneurysm treatments reported as safe, effective, or durable: a systematic review and meta-analysis.

2. thieme-connect.com thieme-connect.com/products/ejournals/pdf/10.1055/s-0045-1810087.pdf

Real-World Outcomes of Endovascular Management of ... This study examines the demographic and clinical profiles of patients with IAs, evaluates the success of various endovascular techniques, and ...

3. ahajournals.org ahajournals.org/doi/10.1161/SVIN.123.001118

Systematic Review and Meta‐Analysis of Endovascular ... We observed that the coil‐based endovascular therapy provides acceptable rates of complete occlusion, and these rates are improved in balloon‐assisted coils.

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3296500/

Endovascular Treatment of Unruptured Intracranial ... On the other hand, adverse outcomes after surgery or coiling of unruptured aneurysms were in the range of 25% and 10%, respectively. A report by Juvela et al, ...

5. nature.com nature.com/articles/s41598-025-92298-w

Impact of aneurysm sac size on the effectiveness ... - Nature Results indicate that coiling significantly reduces rupture risk, with larger sac volumes demonstrating a more pronounced decrease in high-risk hemodynamic ...

6. sciencedirect.com sciencedirect.com/science/article/pii/S2096360220300430

Safety and efficacy of complete versus near ... Initial complete treatment may lead to higher complication rates and good clinical outcomes at follow-up. Stent placement may enhance progressive aneurysm ...

7. mdpi.com mdpi.com/2227-9059/12/6/1231

A 5-Year Follow-Up after Endovascular Treatment of 402 ... Brilstra et al. reported a complication rate of 12%, aneurysm rupture of 2.4% and ischemic events of 8.5% in a series of 1256 aneurysms treated ...

8. ajnr.org ajnr.org/content/44/6/634

A Pragmatic Randomized Trial Comparing Surgical ... CONCLUSIONS: Surgical clipping is more effective than endovascular treatment of unruptured intracranial aneurysms in terms of the frequency of ...