E-264 A Novel Temporary Balloon-Stent Device for Adjunctive Aneurysm Protection During Embolization

Introduction Approximately 30,000 patients experience ruptured aneurysms annually. Rupture is fatal in 50% of cases, and among those who survive, 66% suffer permanent neurological morbidity. Compliant balloons are commonly used to facilitate coil embolization of wide-necked ruptured aneurysms, however there is an increased risk of ischemia due to compromise of parent artery blood flow during embolization. Additionally, balloon inflation/deflation cycles can cause blood vessel trauma. The proposed balloon-stent device is a temporary adjunctive device composed of a self-expandable nitinol mesh structure that covers the aneurysm neck preventing intra-aneurysmal device protrusion. Unlike a balloon inflation, this design also allows blood to perfuse through the device and parent artery, thereby reducing the risk of ischemia. Materials and Methods The prototype balloon-stent is composed of a fine mesh with 250µm pores (figure 1a) up to 4x smaller area than current flow diverters. Quantification of the prototype’s radial force, flow disruption effects, and ease of delivery/retrieval have been measured by the Bioengineering Devices Lab (BDL) at Northern Arizona University (NAU) using a hybrid DMA-rheometer (HR2, TA Instruments) and an advanced flow system. Radial force measurements from the DMA-rheometer were compared to those of control devices (Scepter-C and LVIS Jr.-Microvention). A sophisticated physiologically-relevant benchtop flow system was used to quantify flow disruption effects via the pressure drop measurements in 3D-printed parent vessels, across prototype and control devices. The flow system includes a programmable pulsatile pump system, mechanically relevant 3D-printed models, pressure transducers, and a blood analog fluid. Results The balloon-stent prototypes and control devices were delivered and retrieved from 3D-printed aneurysm models under fluoroscopic imaging (figure 1b). The prototype and stent devices exhibited minimal pressure drop (Fractional Pressure ratio (FPR) >0.95), with prior work showing FPR >0.75 minimizes downstream ischemic risk. The radial force/length of the balloon-stent was ~10 times lower than a self-expanding LVIS-Jr stent and ~80 times lower than a Scepter-C balloon. Conclusion The proposed device is a highly flexible, retrievable, temporary adjunctive medical device for aneurysm treatment. This device provides a smooth protective surface that effectively seals the aneurysm neck during adjunctive treatment. This device can potentially reduce embolic device complications, such as coil protrusion, resulting in a more stable and consistent embolic device placements without the need for temporary balloon protection. Further testing is underway to increase balloon-stent device radial force to maximize aneurysm neck sealing and minimize vessel trauma. Disclosures O. Asgari: 5; C; Northern Arizona University. J. Wells: 5; C; Northern Arizona University, Aneuvas Technologies, Inc. C. Fisher: 5; C; Northern Arizona University. T. Becker: 2; C; United Biologics. 4; C; Aneuvas Technologies, Inc.. 5; C; Northern Arizona University. A. Ducruet: 2; C; Medtronic, Penumbra, Oculus, Stryker, Balt, Koswire. 4; C; Aneuvas Technologies, inc.. 5; C; Barrow Neurological Institute.