3D Printed, Physiologically Compliant, Nonlinear, Simple Equine Pulmonary Artery Phantom: Fabrication Technique and Observations on Mechanical Properties and Pulsatile Behavior
Year: 2020
Type: dissertation
Abstract: The etiology of exercise induced pulmonary hemorrhage, a common affliction of racing horses, is not understood. While this condition manifests as a pulmonary microvascular disease, it is known that large artery function influences microvascular physiology. The extraordinary pulmonary arterial pressure (200 mmHg) of exercising horses suggests that hemodynamic events are likely an important pathophysiologic component of this condition, however the basis of pulse wave energy transmission in large arteries remains controversial and knowledge of equine pulmonary hemodynamics is minimal. Arterial phantoms have a valuable role in the study of arterial hemodynamics, however current material, design and fabrication technology limit replication of the mechanical properties and complex architecture of the arterial system. While additive manufacturing techniques have the potential to improve the utility of arterial phantoms, the 3D printing methods currently used for this purpose are proprietary, expensive and are unable match the physiological compliance of the pulmonary artery. This thesis describes the development of a low cost, open source 3D printing technique to produce simple, physiologically comparable pulmonary artery phantoms. A fused filament fabrication 3D printer was modified to produce thin walled fluted tubes from commercially available polyester-polyurethane filament. Force-displacement and Peterson elastic strain modulus were measured, and a mock circulatory system was used to obtain pulse wave velocity and observe pulse wave behavior. Phantom pulse wave velocities over mean arterial pressures of 7 to 55 mmHg ranged between 1.5 to 5 m·s-1 and compare favorably to preliminary values measured in the horse of 1 to 3 m·s-1. The elastic response of the phantoms was found to be nonlinear in a manner consistent with the behavior of biological arteries. Practical, low cost production of hemodynamic phantoms with wall properties and architecture that closely match pulmonary arterial systems is feasible through use of the techniques presented in this thesis in combination with recent developments in 3D printing technology.
Author: Bruce Guest
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3046072898