Manufacturing of patient‐specific optically accessible airway models by fused deposition modeling

PurposeThe purpose of this paper is to use rapid prototyping technology, in this case fused deposition modeling (FDM), to manufacture 2D and 3D particle image velocimetry (PIV) compatible patient‐specific airway models.Design/methodology/approachThis research has been performed through a case study where patient‐specific airway geometry was used to manufacture a PIV compatible model. The sacrificial kernel of the airways was printed in waterworks™ which is a support material used by Stratasys Maxum FDM devices. Transparent silicone with known refractive index was vacuum casted around the kernel and after curing out, the kernel was removed by washing out in sodium hydroxide.FindingsThe resulting PIV model was tested in an experimental PIV setup to check the PIV compatibility. The results showed that the model performs quite well when the refractive index (RI) of the silicone and the fluid are matched.Research limitations/implicationsDrawbacks such as the surface roughness, due to the size of the printing layers, and the yellowing of the silicone, due to the wash out of the kernel, need to be overcome.Originality/valueThe paper presents the manufacturing process for making complex thick walled patient‐specific PIV models starting from a strong workable sacrificial kernel. This removable kernel is obtained by switching the building and the support materials of the FDM machine. In this way, the kernel was printed in support material while the building material was used to support the kernel during printing. The model was tested in a PIV setup and the results show that the airway model is suitable for performing particle image velocimetry.