Motivation: Phantoms are tremendously useful for advancing quantitative MRI (qMRI). But anthropomorphic phantoms that truly mimic anatomy and the heterogeneity of relaxation parameters in tissue are still out of reach. Goal(s): Our work aims to develop reproducible methods for stable control of T1 modulation in UV curable hydrogels without paramagnetic ions that often diffuse without water-tight boundaries. Approach: We modulate T1 by modifying the polymeric network of our polyacrylamide-polyethylene glycol (pAA-PEGDA) hydrogels,enabling boundaryless T1 contrast between compartments. Results: Our solution is able to bypass issues of dopant diffusion to create stable, precisely bounded regions of hydrogel with distinct T1 values. Impact: A reliable, quantitative method for T1 modification in boundaryless hydrogel systems presents a significant opportunity for development in anthropomorphic phantoms. These phantoms have the potential to accelerate the development of quantitative MRI by making research more standardized, reliable, and accessible.
Falk et al. (Tue,) studied this question.