Larger studies are needed to develop individualized approaches to retreatment, the researchers conclude.
Occasionally, intracranial aneurysms treated using an intra-aneurysmal flow disruptor require retreatment, but this can be accomplished with a high degree of successful occlusion and safety, according to a retrospective analysis published online August 28, 2018, ahead of print in the Journal of NeuroInterventional Surgery.
The intra-aneurysmal flow disruptor is placed within the aneurysm cavity and leaves the parent artery unaffected. Introduced in 2011 as a treatment for wide-necked and bifurcation aneurysms, the Woven Endobridge (WEB) device (Sequent Medical, Aliso Viejo, CA), does not require concomitant use of long-term antiplatelet therapy, making it a treatment option for both ruptured and unruptured aneurysms.
Mid-term outcomes of multicenter studies have shown occlusion rates with the WEB device that are superior to coiling, with or without stent placement. “However, aneurysm recurrence may occur and a subset of these recurrent aneurysms might require retreatment,” note Christoph Kabbasch, MD (University Hospital of Cologne, Germany), and colleagues in the new paper.
“The management of residual aneurysms after WEB implantation is potentially different from that resulting from coil compaction or after flow diverter use. It may thus be challenging, because retreatment options have not been well defined and the long-term angiographic outcome after retreatment remains uncertain,” they add.
To better evaluate the feasibility of retreatment, Kabbasch and colleagues conducted a multicenter study, analyzing outcomes of 121 patients with 122 aneurysms who underwent endovascular retreatment after WEB implantation at one of three German tertiary care centers. Angiographic control was available for 103 aneurysms (84.4%). At the latest available follow-up, the rate of complete occlusion was 68.9% and the rate of adequate occlusion was 87.4%.
Among the 122 aneurysms, 15 required retreatment. Ten of these were true aneurysm remnants, and five were neck remnants. Of the aneurysms requiring retreatment, six were initially treated with the WEB only, two were previously treated by coiling, and seven were large aneurysms that were treated with a multimodal approach.
Reasons for retreatment were WEB migration in six patients, initial incomplete occlusion in five, and WEB compression in four. Retreatment strategies were coiling in four patients, stent-assisted coiling in seven, flow diversion in three, and placement of an additional WEB in one patient. All the procedures were technically successful, and there were no procedure-related complications.
Retreatment Largely Successful
In total, 11 of the 15 retreated patients were available for angiographic follow-up after a median of 23 months following retreatment. Complete occlusion was obtained in eight of the 11 aneurysms. Neck remnants were present in the other three, leading to further retreatment.
The authors conclude from these findings that “retreatment of recurrent and residual aneurysms after initial WEB implantation can be accomplished with a high degree of technical success and with low morbidity. The efficacy of endovascular aneurysm retreatment is good, with adequate aneurysm occlusion seen in all of our cases at mid-term follow-up.”
They also acknowledge that larger studies should be undertaken to “develop individualized management strategies for treatment of recurrent and residual aneurysms after WEB embolization.”
Kabbasch C, Goertz L, Siebert E, et al. . J NeuroIntervent Surg. 2018;Epub ahead of print.
Kabbasch reports serving as a consultant for Acandis GmbH (Pforzheim, Germany).