Modular breast and tumor perfusion phantoms for validation of 4D dynamic contrast-enhanced dedicated breast CT

Breast tumors are heterogeneous, complicating diagnosis and treatment. Four-dimensional dynamic contrast-enhanced dedicated breast CT (4D DCE-bCT) is a novel imaging technique designed to detect the full extent of tumor heterogeneity by imaging the wash-in and wash-out of iodinated contrast with high spatial and temporal resolution. This study aims to develop breast tumor perfusion phantoms to validate 4D DCE-bCT. Three tumor phantoms were 3D-printed with clear resin material. The first phantom includes eight internal channels of 0.8mm and 1mm diameter. The second has similar channels with 0.3mm leaky vessels into an outer shell. The third features gyroid structures with 1.3mm and 1.5mm pores. These phantoms were integrated into a breast perfusion model, consisting of a 3D-printed breast filled with olive oil to simulate fatty tissue. A flow setup with programmable syringe pumps generated contrast wash-in of up to 6mg I/mL over 100s and wash-out over 200s. Time-intensity curves were analyzed in four regions of interest, focusing on areas with varying channel and pore sizes and at the phantom entrance and exit. Dynamic images showed the expected wash-in and wash-out at the phantom entrance and exit. The channel phantom showed 2.5 times higher enhancement in larger channels. The leaking outer shell demonstrated contrast pooling with 30s delayed wash-out. The gyroid phantom showed no differences between the two sides. This study presents the development of 3D-printed breast tumor perfusion phantoms and points to the feasibility of using 4D DCE-bCT to image detailed perfusion patterns.