Biocompatibility and tissue integration of endovascular implants used in intracranial aneurysms

Abstract

Introduction: In the modern management of intracranial aneurysms, the endovascular method has become a more frequently used method of treatment, especially the use of flow-diverters (FD) and coil embolization devices. These implants act as intravascular scaffolds that alter the hemodynamic and the biological response at the aneurysm affected artery interface. One of the critical components of the long-term success of this method is the biocompatibility and tissue integration of these implants. The aim of the study: Synthesizing current evidence on the host-implant interaction and evaluating the impact of the material and surface modifications on the healing process in endovascular treatment of intracranial aneurysms. Materials and methods: Research of scientific literature, from electronic databases such as PubMed, Web of Science and ScienceDirect, published in the last decade that addresses biocompatibility, endothelialization and tissue integration of intracranial aneurysms endovascular treatment. Results: Studies have shown a correlation between in-stent thrombosis, stenosis and the use of phenoxhydrophilic polymer-coated devices, in 77.6% of cases, compared to 66.2% in the use of flowdiverters. The next generation of FD is the bioresorbable type, which has shown reduction of chronic inflammation, side branch occlusion, device induced stenosis and imaging artefacts, while increasing the use in pediatric applications. Poly-L-lactic acid-coated magnesium coated FD and bare magnesium coated FD have excellent biocompatibility, but the bioresorption in case of the Poly-L-lactic acidcoated magnesium FD was delayed. Studies have also shown no significant difference between fibrinbased coated and non-coated flow-diverters, both having similar blood and tissue compatibility. However, current data regarding the relationship between endovascular devices, endothelialization and biocompatibility has largely been derived from preclinical animal models, therefore further studies are necessary. Conclusion: Overall, device material and surface modification significantly influence biocompatibility and vascular healing in endovascular implants of intracranial aneurysms, with bioresorbable flow diverters showing promising reductions in chronic inflammation and device-related complications. However, as most evidence derives from preclinical models, well-designed prospective human studies are essential to validate these biological advantages and their impact on long-term clinical outcomes.