Development of 3-D Printed Optically Clear Rigid Anatomical Vessels for Particle Image Velocimetry Analysis in Cardiovascular Flow

In recent years, blood flow analysis of diseased arterial mock vessels using particle image velocimetry (PIV) has been hampered by the inability to fabricate optically clear anatomical vessel models that realistically replicate the complex morphology of arterial vessels and provide highly resolved flow images of flow tracer particles. The aim of the present work is to introduce an approach for producing optically clear rigid anatomical models that are suitable for PIV analysis using a common 3-D SLA inkjet printing process (using a Formlabs Form 2 3-D printer) and stock clear resin (RS-F2-GPCL-04). By matching the index of refraction (IOR) of the working fluid to the stock clear resin material, and by printing the part in a 45-degree print orientation, a clear anatomical model that allows clear visualization of flow tracer particles can be produced which yields highly resolved flow images for PIV analyses. However, a 45-degree print orientation increases the need for post processing due to an increased amount of printed support material. During post processing, the part must be wet sanded in several steps and surface finished with Novus Plastic Polish 3 Step System to achieve the final surface finish needed to yield high quality flow images. The fabrication methodology of the clear anatomical models is described in detail.