Posted by: arisfil | March 6, 2008

Clip or Coil ?


This is the dilemma that cerebrovascular neurosurgery concerning cerebral aneurysms has to answer in everyday practice. Endovascular neurosurgery has entered the world of aneurysms. The results compared to open microneurosurgical procedures, undergo careful research and study. ISAT (International Subarachnoid Aneurysm Trial) study published in Lancet (2002 and 2005) revealed that the subgroup of patients that met the inclusion criteria and received coil embolization had a greater likelihood of being independent at 1 year (2002). A follow-up analysis in 2005 revealed that this effect appeared durable “for at least 7 years”.

In the follow-up study published in JNS  (J Neurosurg 108:437–442, 2008) by Mitchell et al, further consideration should affect our neurosurgical decision. The question addressed is whether patient’s age affects the decision of clipping an aneurysm or embolizing it. The authors concluded that in patients under 40, clipping would be likely to result in better long-term outcome than embolization. But what is the factor that rendered this difference in relation to age ? The study indicated that rebleeding rates should be more carefully studied. It was found that postprocedural rebleeding rates were higher in the coil embolization group. The rebleeding rate is related to age so a younger patient treated by embolization may show a greater rebleeding rate that an older patient with similar SAH characteristics.


The authors show us a well structured follow-up analysis and utilize the results of the best up-to date trial concerning SAH. A lot of biases are acknowledged by the authors. These results use a specific subgroup of patients (<25% of the total SAH). Life expectancy should also be considered. Endovascular neurosurgery is going to face an extended technical upgrade the following years. What about unruptured aneurysms ? Can these assumptions applied to posterior circulation aneurysms and middle cerebral aneurysms ? The dilemma stays strong and Professor R. Heros designs the route: “patients with SAH benefit from being cared for a center where both open microsurgery and endovascular surgery are available and where ideally the recommendation of one or the other form of therapy is tailored to each patient with relative freedom from disciplinary or financial biases“.

Papers update:

Mitchell et al, Could late rebleeding overturn the superiority of cranial aneurysm coil embolization over clip ligation seen in the International Subarachnoid Aneurysm Trial? J Neurosurg 108:437–442, 2008 – FREE ARTICLE 

Heros RCJ Neurosurg. 2008 Mar;108(3):433-5.

Molyneux et al, International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised trial, Lancet. 2002 Oct 26;360(9342):1267-74. – ABSTRACT

Molyneux et al, International subarachnoid aneurysm trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised comparison of effects on survival, dependency, seizures, rebleeding, subgroups, and aneurysm occlusion. Lancet. 2005 Sep 3-9;366(9488):809-17 – ABSTRACT 

GOOGLE GROUPS Encephalos Discussion Thread:

Cerebral Aneurysms – Clip or Coil ?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: