Persistent Blood Flow inside the Woven EndoBridge Device More Than 6 Months after Intracranial Aneurysm Treatment: Frequency, Mechanisms, and Management—A Retrospective Single-Center Study

Abstract

BACKGROUND AND PURPOSE: Due to its high safety and great efficacy, flow disruption with the Woven EndoBridge (WEB) device is increasingly used to treat intracranial aneurysms. We recently identified patients with intracranial aneurysm treated with the WEB who presented with residual blood flow inside the device ("contrast-in-WEB" phenomenon) more than 6 months posttreatment. This series reports the frequency and underlying mechanisms and discusses management of this phenomenon. MATERIALS AND METHODS:All patients presenting with the contrast-in-WEB phenomenon in the prospectively collected data base of patients with aneurysm treated with the WEB were retrospectively collected and analyzed.RESULTS: From June 2011 to February 2019, one hundred twenty-seven patients with 133 aneurysms were treated with the WEB and had DSA follow-up at 6 months or later. Eight patients (6.3%) presented with the phenomenon. All aneurysms were wideneck bifurcation aneurysms, including 7 unruptured and 1 ruptured aneurysm located at the MCA (5 aneurysms), anterior communicating artery (2 aneurysms), and basilar artery (1 aneurysm). All except 1 patient received dual-antiplatelet therapy preprocedure. All except 1 patient received dual-antiplatelet therapy postoperatively for at least 1 month. The most likely mechanism of the phenomenon is the absence of intradevice thrombosis related to perioperative dual-antiplatelet medication. The phenomenon is also likely associated with a low risk of bleeding except when there is residual blood flow against the aneurysm wall or in the dome.CONCLUSIONS: Contrast-in-WEB is a relatively rare phenomenon possibly induced by dual-antiplatelet therapy continued post-WEB procedure. In most cases, no additional treatment is required.

Long-term efficacy and safety of WovenEndoBridge (WEB)-assisted cerebral aneurysm embolization

“…Periprocedural complication, technical success, treatment-related morbidity, and mortality rates were in line with previously published data. 3,5,8,10–12,15,16 Postprocedural subarachnoid hemorrhage was not seen in our patients through a follow-up period consistent with some studies. 11,14 Our additional device usage rate was 10% for the WEB-assisted treatments in the range of the literature.…”

“…Adequate occlusion rates of the WEB implantations were reported as 56-97% for 1-year follow-up. [2][3][4][5][6][7][8][10][11][12][13][14][15][16] Our first year and latest adequate occlusion rates (87% for both) are within the range of previously published papers and higher than other therapies for wide neck or bifurcation aneurysms. 2,7,8,[10][11][12][13][14][15][16] The recurrence rate of WEB implantations in our study was low (13%).…”

“…[2][3][4][5][6][7][8][10][11][12][13][14][15][16] Our first year and latest adequate occlusion rates (87% for both) are within the range of previously published papers and higher than other therapies for wide neck or bifurcation aneurysms. 2,7,8,[10][11][12][13][14][15][16] The recurrence rate of WEB implantations in our study was low (13%). Most of our aneurysms were improved or stable in a relatively long-term period.…”

“…[4][5][6][7] Animal and human pilot studies revealed that intra-aneurysmal thrombus, aneurysm morphology, device migration to the aneurysmal fundus, and compression/compaction of the WEB had been associated with recurrences. [5][6][7][8][9] However, very few studies explored aneurysm characteristics potentially associated with occlusion rates in a midterm period. 2,3,10 Also, long-term compaction, compression, migration, and recurrence rates of the WEB remain unknown.…”

Recurrent and Residual Aneurysms After Woven EndoBridge (WEB) Therapy: What’s Next?

“…There is a plethora of evidence in the current literature demonstrating WEB's effectiveness and safety for the treatment of wide neck bifurcation aneurysms [23][24][25][26][27][28][29][30]. Most recent data demonstrate that the overall rate of adequate aneurysm occlusion at the last follow-up after WEB therapy is approximately 80% [2][3].…”