Rapid prototyping compliant arterial phantoms for in-vitro studies and device testing

Abstract

BackgroundCompliant vascular phantoms are desirable for in-vitro patient-specific experiments and device testing. TangoPlus FullCure 930® is a commercially available rubber-like material that can be used for PolyJet rapid prototyping. This work aims to gather preliminary data on the distensibility of this material, in order to assess the feasibility of its use in the context of experimental cardiovascular modelling.MethodsThe descending aorta anatomy of a volunteer was modelled in 3D from cardiovascular magnetic resonance (CMR) images and rapid prototyped using TangoPlus. The model was printed with a range of increasing wall thicknesses (0.6, 0.7, 0.8, 1.0 and 1.5 mm), keeping the lumen of the vessel constant. Models were also printed in both vertical and horizontal orientations, thus resulting in a total of ten specimens. Compliance tests were performed by monitoring pressure variations while gradually increasing and decreasing internal volume. Knowledge of distensibility was thus derived and then implemented with CMR data to test two applications. Firstly, a patient-specific compliant model of hypoplastic aorta suitable for connection in a mock circulatory loop for in-vitro tests was manufactured. Secondly, the right ventricular outflow tract (RVOT) of a patient necessitating pulmonary valve replacement was printed in order to physically test device insertion and assess patient’s suitability for percutaneous pulmonary valve intervention.ResultsThe distensibility of the material was identified in a range from 6.5 × 10-3 mmHg-1 for the 0.6 mm case, to 3.0 × 10-3 mmHg-1 for the 1.5 mm case. The models printed in the vertical orientation were always more compliant than their horizontal counterpart. Rapid prototyping of a compliant hypoplastic aorta and of a RVOT anatomical model were both feasible. Device insertion in the RVOT model was successful.ConclusionValues of distensibility, compared with literature data, show that TangoPlus is suitable for manufacturing arterial phantoms, with the added benefit of being compatible with PolyJet printing, thus guaranteeing representative anatomical finishing, and quick and inexpensive fabrication. The appealing possibility of printing models of non-uniform wall thickness, resembling more closely certain physiological scenarios, can also be explored. However, this material appears to be too stiff for modelling the more compliant systemic venous system.

Using 3D printed models for planning and guidance during endovascular intervention: a technical advance

“…3D printed models have been used for surgical training and education (6), creation of custom airway implants (7), surgical planning for congenital heart disease (8,9), and for aortic aneurysm repair (1). Unfortunately, these applications used proprietary software (1,7,8) or expensive on-site printers and printing services (6)(7)(8)(9).…”

Cognitive AutonomouS CAtheters Operating in Dynamic Environments

“…A first set was printed from HeartPrintFlex (wall thickness 1.5 mm). The mechanical properties approach those of the human vasculature 44 as was verified through uniaxial tensile tests. Utilizing multimaterial inkjet, 3D printing calcifications can be incorporated into this model ( Fig.…”

3D Printing Cardiovascular Anatomy: A Single-Centre Experience

“…With advances in 3D printing technology, models such as silicone are becoming compatible with the printers, thus opening interesting avenues of research. One of the first 3D printing compatible compliant materials was a commercially available compound (TangoPlus FullCure) [27]. A study was carried out to evaluate the range of distensibility that can be implemented by models of varying thickness printed with such materials.…”