Design of a 3D printed coronary artery model for CT optimization

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Radiology

Background:

• CT coronary angiography (CCTA) requires precise imaging protocols for accurate diagnosis.
• Developing realistic phantoms is crucial for optimizing CCTA protocols and improving image quality.
• Existing phantom materials may not accurately replicate in vivo coronary artery characteristics.

Purpose of the Study:

• To design and validate a custom phantom for optimizing CT coronary angiography (CCTA) protocols.
• To identify the most suitable material and method for creating a coronary artery phantom that mimics in vivo conditions.
• To evaluate the phantom's utility in assessing different CCTA imaging parameters.

Main Methods:

• Collected in vivo coronary artery data (Hounsfield Units, diameters) from 43 CCTA scans.
• Tested four materials (glycerine/gelatine/water mixtures, pig hearts, Ecoflex™ silicone) for phantom creation.
• Utilized 3D printing to create an artery model, cast with Ecoflex™, and filled with contrast agent for scanning at varying CT parameters (mA, ASiR-V).

Main Results:

• Ecoflex™ silicone and 3D printed models provided the most suitable representation of coronary arteries compared to other materials.
• Contrast-filled Ecoflex™ phantoms achieved a mean HU of 318 ± 4, with a diameter of 4.4 mm.
• Pig heart phantoms showed lower HU (209 ± 5) and visualization issues at higher iterative reconstruction levels.

Conclusions:

• A custom-designed phantom utilizing a 3D printed model and Ecoflex™ silicone casting is the optimal solution for coronary artery phantoms.
• This 3D printing approach offers a cost-effective method for optimizing CT imaging protocols.
• The developed phantom can aid in refining CCTA protocols for improved diagnostic accuracy.