The device is probably not indicated in aneurysms that are large, partially thrombosed, or recurrent, the investigators conclude.
Despite good overall aneurysm repair using the Woven EndoBridge (WEB) device, it may not be the solution for some of the more difficult-to-treat aneurysms, according to a German study recently published online ahead of print in the Journal of NeuroInterventional Surgery.
Commenting on the study for Neurovascular Exchange, Laurent Pierot, MD (Hôpital Maison-Blanche, Reims, France), noted that “intrasaccular flow disruption has caused fundamental changes in the management of wide-neck bifurcation aneurysms. As it is a recent and innovative treatment, it is important to understand precisely what are the [correct] indications for this kind of treatment and in which situations the risk of having relatively poor anatomical results is high.”
Christoph Kabbasch, MD (University Hospital of Cologne, Germany), and colleagues evaluated rates of aneurysm occlusion among 113 patients (mean age 58.9 ± 11.9 years) with 114 aneurysms (mean size 8.6 ± 4.6 mm) that were successfully treated using the WEB device (Sequent Medical, Aliso Viejo, CA) at one of three German tertiary care centers between May 2011 and February 2018.
Aneurysm occlusion was evaluated using the Raymond-Roy occlusion classification. Patient characteristics, anatomical details, and procedural aspects were retrospectively collected. The researchers then looked at how these factors related to aneurysm occlusion and recurrence.
Among 98 patients for whom 6-month angiographic follow-up was available, complete occlusion was achieved in 62.2%. Neck remnants occurred in 21.4% and aneurysm remnants in 16.3%. [CC1] The rate of aneurysm recurrence was 15.3%.
Factors associated with aneurysm remnant were initial partial aneurysm thrombosis, recurrent aneurysms, aneurysm size, and treatment by coil in addition to WEB.
Predictors of Aneurysm Remnant
|
|
Remnant (n = 16) |
Adequate Occlusion (n = 82) |
P Value |
|
Initial Partial Aneurysm Thrombosis |
33% |
67% |
< 0.01 |
|
Recurrent Aneurysm |
50% |
50% |
0.02 |
|
Dome Width, mm |
7.0 ± 2.9 |
10.5 ± 6.1 |
0.04 |
|
Height, mm |
7.3 ± 3.2 |
11.8 ± 7.9 |
0.04 |
|
Maximum Diameter, mm |
8.0 ± 3.4 |
13.3 ± 8.0 |
0.02 |
|
Treatment With WEB and Coil |
50% |
50% |
< 0.01 |
Predictors of aneurysm recurrence were initial partial aneurysm thrombosis, increasing aneurysm size, and additional coiling.
Predictors of Aneurysm Recurrence
|
|
Yes (n = 15) |
No (n = 83) |
P Value |
|
Initial Partial Aneurysm Thrombosis |
83% |
17% |
< 0.01 |
|
Dome Width, mm |
11.0 ± 5.9 |
7.0 ± 2.9 |
0.02 |
|
Height, mm |
13.6 ± 6.9 |
7.0±3.2 |
< 0.01 |
|
Maximum Diameter, mm |
14.4 ± 7.5 |
7.9 ± 3.4 |
0.01 |
|
Dome/Neck Ratio |
2.3 ± 1.4 |
1.6 ± 0.6 |
< 0.01 |
|
Aspect Ration |
2.7 ± 1.0 |
1.7 ± 1.0 |
< 0.01 |
|
Width/Height Ratio |
0.8 ± 0.3 |
1.0 ± 0.3 |
0.04 |
|
Treatment With WEB and Coil |
50% |
50% |
< 0.01 |
In a subgroup analysis of 71 aneurysms treated with WEB only, the rate of aneurysm recurrence was 11.3%. Initial incomplete occlusion and male sex were associated with aneurysm remnants (P < 0.05). In addition, aneurysm height correlated with aneurysm recurrence (P = 0.008), as did aspect ratio (P = 0.012).
According to Pierot, the outcomes are similar to those of the European Good Clinical Practice studies (ie, WEBCAST, WEBCAST 2, and French Observatory), despite the inclusion of difficult-to-treat aneurysms, such as those that are large or partially thrombosed.
Not for All Aneurysms
Pierot said the study helps clarify cases in which outcomes might be suboptimal. Based on the findings, one can conclude that the WEB device probably isn’t suitable for partially thrombosed aneurysms, he explained. “As for coiling, there is probably a risk of migration of the embolic material in the thrombosed part of the aneurysm, leading to aneurysm recurrence.”
Secondly, Pierot concluded, “WEB treatment is also probably not a good indication in large aneurysms. As of now, the largest WEB device is 11 mm in transverse diameter. As the device has to be oversized by 1 mm in transverse diameter, it means that aneurysm treatment with WEB only is probably indicated [only] in aneurysms that have a transverse diameter ≤ 10 mm. For bigger aneurysms, the combination of WEB and coils is not a very good option, according to the results reported in the paper.”
Finally, he added, it appears that “recurrent aneurysms are also aneurysms difficult to treat with WEB.”
Use of the WEB device “in large aneurysms, thrombosed aneurysms, and recurrent aneurysms have to be carefully evaluated and other therapeutic options have to be discussed,” he recommended.
Source:
- Kabbasch C, Goertz L, Siebert E, et al. Factors that determine aneurysm occlusion after
- embolization with the Woven EndoBridge (WEB). J NeuroInter Surg. 2018;Epub ahead of print.
Disclosures:
- Kabbasch reports serving as consultant for Acandis GmbH (Pforzheim, Germany).
- Pierot reports serving as a consultant for Microvention/Sequent.
