Treatment of experimental aneurysms with a GPX embolic agent prototype: preliminary angiographic and histological results

Background Recently, liquid embolic agents have emerged for the endovascular treatment of cerebral aneurysms. Here we describe the in vivo performance of a novel liquid embolization agent (GPX Embolic Device). Methods Elastase-induced aneurysms were embolized with a GPX prototype under balloon assistance. Digital subtraction angiography was performed pre-deployment and immediately after, and at 5, 10, and 30min postdeployment in 10 rabbits and at 1month in 8 rabbits. The early post-deployment intra-aneurysmal flow was graded as unchanged, moderately diminished, or completely absent. At 1month the status of aneurysm occlusion was evaluated. Adhesion to catheter material and migration of GPX was assessed. Results The mean aneurysm neck diameter, width, and height were 3.6±1.0mm, 3.0±0.8mm, and 7.4±1.4mm, respectively. The mean dome-to-neck ratio was 0.9±0.2. Complete stagnation of intra-aneurysmal flow was observed in 9 of 10 aneurysms (90%) within 30min of device deployment. One aneurysm showed moderately diminished intra-aneurysmal flow at 30min. At 1month, 8 aneurysms were completely occluded. There was no evidence of GPX adhesion to the catheter material. Histologically, a leukocyte and foreign body reaction to GPX was detectable 28 days after embolization. Conclusions This is the first preclinical study reporting the performance of a protype version of the GPX Embolic Device in a wide-neck aneurysm model. GPX showed promising results by achieving and maintaining high rates of complete angiographic occlusion, but may induce an inflammatory reaction