An “old” meta-analysis: coiling versus microsurgical clipping in the treatment of unruptured MCA aneurysms

Key point:

    • To compare endovascular coiling with microsurgical clipping among adults with unruptured middle cerebral artery aneurysms (MCAA) by conducting a meta-analysis.

The widespread use of neurovascular imaging has increased the amount of intracranial aneurysms eccidentally detected. Although the lifetime risk of aneurysmal rupture in many cases is relatively small (approximately 1% per year), rupture can results in permanent neurological deficits or death, the reason why often patients may desire the treatment of unruptured aneurysms to prevent later rupture. In the last 2 decades, incremental improvements of endovascular coiling techniques has led to significant controversy regarding the ideal management strategy for unruptured intracranial aneurysms of the cerebral vessels. In this paper, published online February, 2018, on Neurosurgery, Authors performed a meta-analysis of studies to compare endovascular coiling and microsurgical
clipping with regard to the safety and efficacy of the treatment of unruptured middle cerebral artery aneurysms
(MCAA), including 37 articles with 3352 aneurysms (2162 clipping, 1190 coiling). Results are reported in the following table.


This meta-analysis showed the superiority of the surgical clipping vs. the endovascular coiling in terms of occlusion rate (clip occlusion rate = 94.2%, 95% CI, 87.6%-97.4% vs coil occlusion rate = 53.2%, 95% CI, 45.0%-61.1%) and no difference in terms of neurological outcome (clip favorable neurological outcome rate = 97.9%,95% CI, 96.8%-98.6% vs coil favorable neurological outcome rate = 95.1%, 95% CI, 93.1%-96.5%).

Our question is:

Is this study really actual? 

What is sure is that at least 2 major decisions must be made when an unruptured intracranial aneurysm is identified:

  • Whether the "patient" (and not only the aneurysm) should be treated.
  • Whether it should be treated with "endovascular techniques" (and not only non assisted coiling) or with microsurgical clipping (possibly with a wide range of aneurysm clips available).


  • * Johnson AK, Heiferman DM, Lopes DK. Stent-assisted embolization of 100 middle cerebral artery aneurysms. J Neurosurg. 2013 May;118(5):950-5. doi: 10.3171/2013.1.JNS121298. Epub 2013 Feb 8.
  • Alreshidi M, Cote DJ, Dasenbrock HH, Acosta M, Can A, Doucette J, Simjian T, Hulou MM, Wheeler LA, Huang K, Zaidi HA, Du R, Aziz-Sultan MA, Mekary RA, Smith TR. Coiling Versus Microsurgical Clipping in the Treatment of Unruptured Middle Cerebral Artery Aneurysms: A Meta-Analysis. Neurosurgery. 2018 Feb 9. doi: 10.1093/neuros/nyx623. [Epub ahead of print]

Leave a Reply