Controversy surrounding flow diverters in the sylvian artery - Ep.2/4

• Flow diverter in the treatment of MCA aneurysms:

In this episode we begin to discuss the risk of complications when using FD in

the MCA bifurcation. Data in the literature, although old (2017), show a

complication rate of around 20% and morbidity of 10% in this type of case.7. Most

recent data from 2022 shows a morbidity rate of 8.6% and mortality of 2%1.

Another study from 2022 demonstrated a complete aneurysm occlusion rate of

80% and a thromboembolic complication rate of 16.7%8.

An important point raised by Pr. Adnan Siddiqui is that we must be cautious when

analyzing these papers as the aneurysms treated are more complex and often

not possible with other techniques such as the SLICE 2024 MCA aneurysm and

the complications should be higher. Another discussion was about the

reproducibility of the technique and there was a reproducibility rate of

approximately 7.9.

Furthermore, we discuss the durability of the treatment, which is approximately 9.5.

At the end of the episode, Pr. Vincent Costalat demonstrated a similar case of

MCA bifurcation aneurysm recanalized after treatment with coils. The same

strategy of using FD covering a branch of the MCA was carried out and, although

the patient was tested for antiaggregation with good results, he had ischemia in

the branch covered by the FD 9 days after treatment. Pr. Costalat raised the

discussion that perhaps this strategy should not be the first one in these cases.

• Further reading:

1) Piano, M. et al. Flow diverter devices in the treatment of complex middle cerebral artery

aneurysms when surgical and endovascular treatments are challenging. J. Stroke Cerebrovasc.

Dis. 31, 106760 (2022)

2) BhogalP,AlMatterM,Ba ̈znerH,etal.Flowdiversionforthetreat- ment of MCA bifurcation

aneurysms: a single centre experience. Front Neurol 2017;8:20 CrossRef Medline

3) BhogalP,MartinezR,GansladtO,etal.Managementofunruptured saccular aneurysms of the M1

segment with flow diversion: a single centre experience. Clin Neuroradiol 2016 Dec 11. [Epub

ahead of print] CrossRef Medline

4) Briganti F, Napoli M, Leone G, et al. Treatment of intracranial an- eurysms by flow diverter

devices: long-term results from a single center. Eur J Radiol 2014;83:1683–90 CrossRef Medline

5) Caroff J, Neki H, Mihalea C, et al. Flow-diverter stents for the treat- ment of saccular middle

cerebral artery bifurcation aneurysms. AJNR Am J Neuroradiol 2016;37:279 – 84 CrossRef

Medline

6) IosifC,MounayerC,YavuzK,etal.Middlecerebralarterybifurca- tion aneurysms treated by

extrasaccular flow diverters: midterm angiographic evolution and clinical outcome. AJNR Am J

Neurora- diol 2017;38:310 –16 CrossRef Medline

7) F. Cagnazzo, D. Mantilla, P.-H. Lefevre, C. Dargazanli, G. Gascou and V. Costalat American

Journal of Neuroradiology December 2017, 38 (12) 2289-2294

8) Diestro JDB, Adeeb N, Dibas M, et al. Flow Diversion for Middle Cerebral Artery Aneurysms: An

International Cohort Study. Neurosurgery. 2021;89(6):1112-1121