Scanning electron microscopy analysis of microcatheter inner lining damage and thrombogenesis in coil embolization

PurposeCoil embolization is a standard treatment for intracranial aneurysms. However, ischemic complications remain a concern, despite advancements in technology and the use of antithrombotic agents. Microcatheter-related thrombogenesis has been identified as a contributing factor to these complications. Although previous studies have focused on external morphological changes, limited data are available on the impact of changes in the inner lining of microcatheters on ischemic events. In this study, we used scanning electron microscopy (SEM) to investigate changes in the inner lining of microcatheters after coil embolization.MethodsFive SL-10, two Phenom 17, and one Echelon 10 microcatheters used in coil embolization procedures were examined using SEM. An unused microcatheter served as a control. The microcatheters were sectioned at various locations and analyzed under high magnification.ResultsSEM provided high-resolution visualization of the inner lining of the microcatheter, revealing morphological alterations that were undetectable by light microscopy. The control had an intact membrane, whereas the SL-10 microcatheters showed varying degrees of damage. Microcatheters used in multiple-coil deliveries exhibited extensive peeling and cracking of the inner lining. Additionally, clots composed of red blood cells were observed inside the microcatheters. The same morphological changes in the inner linings were observed in other types of microcatheters, such as Phenom 17 and Echelon 10.ConclusionSEM showed that repeated microcatheter use in coil embolization damages the inner lining, potentially contributing to thrombus formation and ischemic complications. These findings highlight the need to investigate microcatheter durability and thromboresistance to mitigate embolization-related ischemic risks.