Creation of brain tissue-mimicking material and multi-material gradient 3D printer for magnetic resonance elastography phantom

3D printing;Magnetic resonance elastography;Brain phantom

DiMonte, Lela ; Georgiadis ; John

关键词: 3D printing;    Magnetic resonance elastography;    Brain phantom;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/72826/Lela_DiMonte.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Magnetic resonance elastography (MRE) is a non-invasive tissue imaging method that measures shear stiffness. While MRE has many benefits, it is not currently used clinically for scanning the human brain, mainly because it has not been validated with independent mechanical property testing methods. This project focused on the creation of a brain tissue-mimicking phantom that simulates both the chemical composition and mechanical properties of human brain tissue. Material development consisted of matching the lipid composition of the brain with alternate natural materials to formulate hydrocolloids (based on gelatin or carrageenan) that were both soft and stable at room temperature. The rheology of the mixture, including extrusion (flow) behavior and mechanical properties, was regulated by manipulating the hydrocolloid material composition. The stiffness of developed materials was tested with rheometry to verify that the stiffness matched that of brain white matter. Phantom development started with creating a 3D printer to extrude soft materials. The printer was further modified to print two materials separately or in mixed ratios so that stiffness could be varied within a print. A phantom was printed with a low- to high-stiffness gradient using a carrageenan-based hydrocolloid. Presence of the gradient in the phantom was then verified successfully with MRE.