Towards a barrier-free anthropomorphic brain phantom for quantitative magnetic resonance imaging: Design, first construction attempt, and challenges

PLoS One. 2023 Jul 12;18(7):e0285432. doi: 10.1371/journal.pone.0285432. eCollection 2023.

Abstract

Existing magnetic resonance imaging (MRI) reference objects, or phantoms, are typically constructed from simple liquid or gel solutions in containers with specific geometric configurations to enable multi-year stability. However, there is a need for phantoms that better mimic the human anatomy without barriers between the tissues. Barriers result in regions without MRI signal between the different tissue mimics, which is an artificial image artifact. We created an anatomically representative 3D structure of the brain that mimicked the T1 and T2 relaxation properties of white and gray matter at 3 T. While the goal was to avoid barriers between tissues, the 3D printed barrier between white and gray matter and other flaws in the construction were visible at 3 T. Stability measurements were made using a portable MRI system operating at 64 mT, and T2 relaxation time was stable from 0 to 22 weeks. The phantom T1 relaxation properties did change from 0 to 10 weeks; however, they did not substantially change between 10 weeks and 22 weeks. The anthropomorphic phantom used a dissolvable mold construction method to better mimic anatomy, which worked in small test objects. The construction process, though, had many challenges. We share this work with the hope that the community can build on our experience.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Brain* / diagnostic imaging
  • Gray Matter / diagnostic imaging
  • Humans
  • Magnetic Resonance Imaging*
  • Magnetic Resonance Spectroscopy
  • Phantoms, Imaging

Grants and funding

S.D.O. and S.E.O. would like to acknowledge support from NIST-PREP (Professional Research Experience Program), performed under the following financial assistance award 70NANB18H006 from U.S. Department of Commerce, National Institute of Standards and Technology. K.V.J. acknowledges research funding from the National Research Council Postdoctoral Fellowship. NIST acknowledges assistance from Hyperfine through a Cooperative Research and Development Agreement (CRADA). K.V.J., S.E.R., and K.E.K. acknowledge funding from the Physical Measurement Laboratory of the National Institute of Standards and Technology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.