3D Printed Dissolvable PVA Structures for Anatomical Phantom Voids
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for creating anatomical phantoms, such as brain ventricles, face challenges in maintaining negative spaces without leaving scars or requiring post-processing, like back-filling and air pocket removal.
Innovation Solution
3D printing using dissolvable materials like PVA filament to create negative spaces, followed by encapsulation in a mold and processing through freeze-thaw cycles to produce a tissue phantom with desired biomechanical properties, allowing for the dissolution of the printed volume to form fluid-filled voids.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If balloons are inflated within liquid hydrogel to create negative spaces, then void structures can be formed, but scars are left on the surface and post-processing is required
Solution Approach 1:
The patent extracts the balloon template from the hydrogel matrix through dissolution rather than mechanical removal. The balloon is replaced with a water-soluble support structure that dissolves in the hydrogel, eliminating the need for extraction and preventing surface scars. This is achieved by incorporating water-soluble materials into the balloon formulation that allow complete dissolution after freezing and thawing cycles.
Solution Approach 2:
The patent changes the chemical composition parameters of the balloon material to be water-soluble, transforming it from a permanent template to a temporary sacrificial structure. This parameter change allows the balloon to dissolve completely in the hydrogel matrix after freezing and thawing, leaving clean negative spaces without surface defects or requiring post-processing removal.
2Manufacturing precision
If balloons are removed after freeze-thaw cycle to create voids, then negative spaces are formed, but air pockets develop requiring back-filling
Solution Approach 1:
The patent applies preliminary action by freezing the hydrogel matrix around the water-soluble balloon before dissolution. The freezing process creates a rigid structure that maintains the negative space integrity during subsequent balloon dissolution. This preliminary freezing action prevents air pocket formation by ensuring the hydrogel matrix is already set and can contain the void space properly when the balloon dissolves.
3Manufacturing precision
If dissolvable materials like PVA filament are used to print 3D structures, then precise negative spaces can be created, but the material must maintain integrity during freeze-thaw cycles
Solution Approach 1:
The patent uses composite materials by combining PVA filament with water-soluble support materials and encapsulating them in a hydrogel matrix. The PVA provides structural integrity and precision during printing and freeze-thaw cycles, while the water-soluble components allow eventual dissolution. The hydrogel encapsulation protects the PVA structure during processing while allowing controlled dissolution afterward to create precise negative spaces.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method effectively creates anatomical phantoms with precise, fluid-filled voids that mimic brain ventricles, enhancing the realism and usability of surgical training models while avoiding post-processing complications.
Implementation Method 1
The printed 3D volume is then dissolved to produce a fluid filled void having the size and shape of the printed 3D volume
Implementation Method 2
A polyvinyl alcohol (PVA) formulation is then poured into the mould to surround and encapsulate an appropriate number of freeze thaw cycles (FTC) are carried out to produce a tissue phantom with the desired biomechanical properties
Data Source
AI summary
Disclosed herein are anatomical simulators produced using three dimensional (3D) printing to produce interior components of the simulator. The method of producing void structures in an anatomical phantom, includes 3D printing one or more structures of one or more desired sub-anatomical features using a dissolvable material; supporting and enclosing the one or more structures in an interior of a mold of the anatomical phantom; filling a remaining internal volume in the interior of the mold between an outer surface of the one or more structures and an inner surface of the mold with a liquid precursor of a matrix material selected to mimic anatomical tissue and processing the liquid precursor to form a tissue mimic matrix material; and dissolving the one or more structures with a fluid selected to dissolve said dissolvable material to produce one or more internal cavities within the tissue mimic matrix material.