Engineering Analysis of Non-Braided Polycaprolactone Bioresorbable Flow Diverters for Aneurysms

Area of Science:

• Biomaterials Science
• Medical Devices
• Endovascular Surgery

Background:

• Permanent metallic flow diverters (FDs) are used for endovascular aneurysm treatment but carry risks.
• Bioresorbable FDs offer a potential solution by degrading after aneurysm healing.

Purpose of the Study:

• To design, fabricate, and characterize a nonbraided, bioresorbable polycaprolactone (PCL) flow diverter (FD).
• To evaluate the mechanical properties, surface characteristics, deployability, and angiographic visibility of the PCL FDs.

Main Methods:

• Fabrication of PCL FDs with varying porosities (50%, 60%, 70%) using hybrid electromelt spinning-fused deposition.
• Characterization using SEM, AFM, and UTM for structural and mechanical properties.
• In vitro testing in a PDMS aneurysm model for deployability and X-ray visibility assessment with BaSO4 and Bi2O3 coatings.

Main Results:

• PCL FDs exhibited satisfactory tensile strength, radial strength, and flexibility comparable to coronary stents.
• Successful deployment through a 4 Fr catheter in an aneurysm model was demonstrated.
• Angiographic visibility improved with increasing concentrations of BaSO4 and Bi2O3 coatings, with Bi2O3 showing slightly higher intensity.

Conclusions:

• The developed nonbraided, bioresorbable PCL FDs show promising engineering characteristics for endovascular aneurysm treatment.
• These devices present a potentially safer alternative to permanent metallic implants.
• Further research and clinical evaluation are warranted.