When is aneurysm clipping recommended?

Indications for Aneurysm Clipping

Microsurgical clipping should be the first choice treatment for unruptured aneurysms in young patients (<40 years), very large or giant aneurysms, and those with high neck-to-dome ratios, as it provides significantly more durable results than endovascular alternatives. 1

Patient-Specific Factors for Clipping

Age Considerations

• Young patients (<40 years): Clipping is preferred due to superior long-term durability 1
• Patients <60 years with aneurysms >5mm: Should be offered treatment, with clipping as a strong consideration 1
• Patients <70 years with aneurysms >10mm: Should receive treatment, with clipping often preferred 1
• Elderly patients (>70 years): Higher surgical risks; endovascular approaches may be more appropriate 1

Aneurysm Characteristics

• Very large or giant aneurysms: Benefit more from surgical clipping 1
• High neck-to-dome ratio aneurysms: Better suited for surgical approaches 1
• Anterior circulation aneurysms in low-risk patients: Clipping provides more durable results 1
• Middle cerebral artery aneurysms: Often anatomically more favorable for clipping 1
• Aneurysms with large intraparenchymal hematomas: Emergency clipping with hematoma evacuation is indicated 1

Ruptured vs. Unruptured Aneurysms

Ruptured Aneurysms

• All symptomatic ruptured aneurysms should be treated urgently to prevent rebleeding 1
• For posterior circulation ruptured aneurysms, coiling is preferred over clipping 1
• For anterior circulation ruptured aneurysms with good clinical grade:
  • Primary coiling is recommended for 1-year outcomes 1
  • Both clipping and coiling are reasonable for long-term outcomes 1

Unruptured Aneurysms

• Small aneurysms (<5mm): Generally managed conservatively 1, 2
• Symptomatic unruptured aneurysms: Should be treated regardless of size 1
• Aneurysms >5mm in patients <60 years: Treatment recommended 1
• Aneurysms >10mm: Treatment strongly recommended in patients <70 years 1

Technical Considerations

• Complete obliteration of the aneurysm should always be the goal 1
• Surgical clipping provides more durable results with lower recurrence rates than coiling 1, 3
• For complex aneurysms, combined approaches (bypass techniques with endovascular procedures) may be necessary 1
• Post-clipping angiography is recommended to confirm complete aneurysm obliteration 1

Decision-Making Algorithm

1. Assess patient age:

   • <40 years: Consider clipping as first option
   • 40-70 years: Evaluate based on aneurysm characteristics

   • 70 years: Consider endovascular approach first

2. Evaluate aneurysm size:

   • <5mm and asymptomatic: Conservative management
   • 5-10mm: Treatment recommended for patients <60 years

   • 10mm: Treatment recommended for patients <70 years

3. Assess aneurysm morphology:

   • High neck-to-dome ratio: Favor clipping
   • Wide neck: Favor clipping
   • Complex morphology: Consider clipping or combined approach

4. Consider aneurysm location:

   • Anterior circulation in low-risk patient: Clipping often preferred
   • Posterior circulation: Endovascular approach often preferred
   • Middle cerebral artery: Often more suitable for clipping

5. Evaluate presence of hematoma:

   • Large intraparenchymal hematoma: Emergency clipping with evacuation

Common Pitfalls and Caveats

• Overreliance on aneurysm size alone can lead to missed treatment opportunities; consider patient age and aneurysm location 1
• Clipping very small aneurysms (<3mm) can be technically challenging with higher complication rates 2
• Surgical experience significantly impacts outcomes; high-volume centers (>35 cases/year) have better results 1
• Long-term follow-up imaging is essential after any treatment to detect recurrence 1
• The decision between clipping and coiling should involve a multidisciplinary team with both neurosurgical and endovascular expertise 1

Surgical clipping remains the gold standard for durability in aneurysm treatment, with endovascular approaches offering less invasive alternatives in specific scenarios. The treatment decision should be tailored based on patient age, aneurysm characteristics, and the expertise available at the treating center.