Intracranial Aneurysms: Coil Embolization

Fig.1 & 2: Angiographic image of the left internal caroid artery injection shows an aneurysm of the left supraclinoid internal carotid artery. Fig.1 without subtraction, Fig.2 with.
Fig.3: Angiographic image after coil embolization (performed because the patient had SAH) reveals a coil within the aneursym.

Coil Embolization Complications

• Complicaton rate 8.6% to 18.6% (median 10.6%), lower than surgical clipping
• Common complications: thrombo-embolic events, perforation of aneurysm, parent artery obstruction, collapsed coil, coil malposition, and coil migration

Coil Embolization versus Aneurysm Clipping

• Less risks of death
• Higher rate of rebleeding (2.4% versus 1%) - why*
  
• Advantages vary depending on location of aneurysm, but coil embolization is beneficial for all sites

*Percentage of complete aneurysm occlusion after coil embolization is lower than with surgical clipping
* Recurrence = refilling of thee neck, sac, dome of a successfully treated aneurysm

What to Choose?

• Not all aneurysms required coil embolization. This depends on size, anatomy and location of aneurysms.
  
• People at increased risk for craniotomy (>65 years, poor clinical status, comorbid conditions)
• Suitability depends on size, anatomy, location of aneurysms (in ophthalmic artery or basilar tip artery)
• Better perform craniotomy if
• >10 mm size
• > 4mm neck
  

Reference:
Ontario Heath Technology Advisory Committee. Coil Embolization for intracrinal aneurysms.