HYDROPHILIC COATINGS DIMINISH ADHESION OF GLUE TO CATHETER - AN IN-VITRO SIMULATION OF NBCA EMBOLIZATION

PURPOSE: To determine whether new hydrophilic microcatheter coatings e xhibit characteristics that diminish the chance of permanent endovascu lar glue adhesion during liquid acrylic embolization. METHODS: Common hydrophilic and nonhydrophilic microcatheters (both flow-directed and over-the-wire) used in neurointerventional procedures were evaluated i n vitro for liquid acrylic (Histoacryl and Avacryl)-to-catheter bond s trength, catheter endovascular friction, and catheter stretch (tensile strength). Sufficient test repetitions were acquired to achieve stati stical significance. RESULTS: The bond strength between hydrophilicall y coated catheters and NBCA was significantly weaker than between nonh ydrophilic catheters and NBCA. Hydrophilic catheter coating reduced dy namic endovascular friction by 30% to 35%, All flow-directed catheters exhibited considerably more stretch (less tensile strength) and there fore were more prone to fracture during withdrawal than over-the-wire systems. Histoacryl bonded to both hydrophilic and nonhydrophilic cath eters with a significantly greater force than did Avacryl, CONCLUSION: Hydrophilically coated catheters should be less likely to exhibit per manent endovascular fixation during acrylic embolization because of a weaker catheter-NBCA bond and because of reduced catheter friction (al lowing a larger portion of any applied catheter withdrawal force to be transmitted to the catheter tip with less force dissipated along the catheter resulting in stretch). A significant difference in NBCA types (Histoacryl and Avacryl) was discovered: Avacryl developed a signific antly weaker bond with all catheter types.