The Source for Neurovascular News and Education

June 13, 2024

In a case series, researchers highlight the importance of careful consideration of EVD placement and use of a platelet-function-based therapy regimen.


Stent-assisted coiling in patients with ruptured aneurysms can be performed with good technical success, according to a case series reported in the Journal of NeuroInterventional Surgery. The researchers say their strict protocol helped them achieve immediate total or near-total aneurysm occlusion in up to 97% of patients treated with a combination of stents and coils.

“In our experience, stent techniques have provided a high rate of technical success without intra- or periprocedural hemorrhage, and with good late neurological outcomes,” write Jose E. Cohen, MD (Hadassah-Hebrew University Medical Center, Jerusalem), and colleagues.

They employed a protocol for stent-based treatment based on a low threshold for external ventricular drain (EVD) placement before stenting, and preprocedure administration of aspirin and clopidogrel with platelet testing to “ensure that response falls within a safe range to limit the risk of both hemorrhage and stent-related thrombus formation.”

Cohen and colleagues conducted a retrospective review of clinical records from 47 patients with acutely ruptured aneurysms treated at their institution with stent techniques during the early acute phase of aneurysmal rupture between June 2011 and June 2016. Of the included patients, 46 had subarachnoid hemorrhage; patients harbored 71 aneurysms, including 56 in the acute phase.

Single-stent techniques were used in the majority of the 56 acute stage aneurysms (n = 39) with dual-stent techniques used in the remainder. Per protocol, EVDs were placed before embolization in 92% of patients.

Only four patients experienced intraprocedure thromboembolic complications due to hyporesponse to antiplatelet therapy. These patients were all treated with stent-assisted coiling and the complications were successfully managed with intra-arterial antiplatelet agents.

The majority of patients (96%) survived the procedures. Among survivors, there was complete aneurysm occlusion at 9- to 12-month follow-up in 90% of patients treated with stent-assisted coiling, in 66% of aneurysms treated with flow-diverter-assisted coiling, and in 86% of aneurysms treated with flow diverter alone.


Reassuring Study

In their discussion of the results, Cohen and colleagues credit the low rate of hemorrhagic complications to the use of flow diverter stents and routine EVD placement prior to embolization in patients with actual or anticipated hydrocephalus.

“In this way, we avoided placing ventriculostomy under double antiplatelet therapy and further reduced the overall risk of hemorrhage,” they write.

In fact, emphasis on the need for careful consideration of EVD placement is among the best feature of the study, commented David F. Kallmes, MD (Mayo Clinic, Rochester, MN). To Neurovascular Exchange, he said the results of this study are incremental and reinforce what has already been published on the topic.

“This study offers more comfort to practitioners that, if needed, stent or flow diverter should be considered,” he said.

However, Kallmes did point out one issue that was not addressed with the case series: the fact that there may be future advances to technology that will facilitate stent and flow-diverter usage in ruptured cases. Specifically, new coatings, materials, or designs could diminish or eradicate risk of thromboembolism, Kallmes said, citing Shield Technology (Medtronic) as one example of ongoing efforts aimed at reducing thrombogenicity.

“There is animal data showing benefit in reducing neointima and some suggestion that thromboembolism is diminished, but this is very early and how clinical trials will be done to prove efficacy remains problematic,” Kallmes said. “That is, who will want to randomize patients to no antiplatelet therapy to show benefit of coatings?”



Cohen JE, Gomori JM, Leker RR, et al. Stent and flow diverter assisted treatment of acutely ruptured brain aneurysms. J NeuroIntervent Surg. 2018;Epub ahead of print.



  • Cohen reported no competing interests.
  • Kallmes reports receiving research funding from and being a consultant for Medtronic.