Abstract 009: Prototyping a Novel Balloon‐Stent Device for Treating Brain Aneurysms
Authors: Clark W. E. , Asgari O. , Becker T. A. 
Published: January 2025

Introduction
Although neurointerventional technologies have advanced for aneurysms, current adjunctive devices such as stents and temporary balloons still present significant limitations. Balloons can provide a uniform surface and neck protection for improved coiling and embolic placement, but also occlude parent artery blood flow and increase the risk of intraoperative ischemia and thrombus formation. Further, their inflation and deflation processes often result in diffuse vessel trauma. Stent technologies can support the parent vessel at the aneurysm, but coils placed behind the stent during aneurysm treatment can become entangled. Additionality, permanent stent placement necessitates long‐term dual antiplatelet therapy (DAPT), presenting substantial bleeding risks to the patient.

This project aimed to develop, build, and validate the Balloon‐Mesh (BM), a unique endovascular device that enhances aneurysm neck protection during embolic device placement while maintaining blood flow in the parent artery distal to the aneurysm. Doing so minimizes the risk of ischemia while providing excellent aneurysm neck protection, setting it apart from existing solutions.
Aim 1
was to design and build BM prototypes for endovascular aneurysm treatment.
Aim 2
was to assess the BM prototype in an
in vitro
aneurysm blood flow model. The impact of this study illustrates how a high‐density mesh device could be superior to current adjunctive devices, improving post‐operative outcomes and signaling a paradigm shift in stent‐assisted embolization technology.

Methods Aim 1
Pressure drop across neurovascular stenosis greater than 25% is an ischemic risk. Fluid simulations showed that a BM device with a pore size of 200 does not pose significant ischemic risk while providing superior aneurysm neck protection. From simulations, three initial BM devices were created. They were designed to be self‐expanding, retrievable, and balloon‐shaped. Each prototype evaluated a different profile to identify the optimal shape for neck protection.

Aim 2
The BM prototypes were deployed in aneurysm models with real‐time pressure recording. Fluoroscopy was utilized to visualize flow and record any variations or complications that might arise during device deployment. The prototype performance was directly compared to a control device (Pipeline Medtronic). Aneurysm neck coverage was evaluated through contrast injections.

Results
All BM prototypes were successfully tracked and deployed at the neck of the aneurysm. Flow analysis shows the BM does not pose an ischemic risk. Fluoroscopy indicates the control device did not significantly reduce the flow inside the aneurysm. By comparison, the BM prototypes significantly reduced flow into and out of the aneurysm while maintaining parent artery flow.

Conclusion

This project delivered on Aims 1 and 2 by developing three BM prototypes that optimized aneurysm neck protection while maintaining parent artery blood flow. The device performance was validated using multiple
in vitro
vessel models. We found that the BM successfully protected the neck of an aneurysm while maintaining parent artery blood flow, eliminating ischemic risk. Additionally, the BM prototypes outperformed the control at minimizing flow into the aneurysm. Future work includes modifying the BM size for various vessels, investigate compatibility with embolic devices (coil/liquid), and
in vivo
testing in preparation for an FDA submission.