Quantitative magnetic resonance imaging phantoms: A review and the need for a system phantom

Abstract

The MRI community is using quantitative mapping techniques to complement qualitative imaging. For quantitative imaging to reach its full potential, it is necessary to analyze measurements across systems and longitudinally. Clinical use of quantitative imaging can be facilitated through adoption and use of a standard system phantom, a calibration/standard reference object, to assess the performance of an MRI machine. The International Society of Magnetic Resonance in Medicine AdHoc Committee on Standards for Quantitative Magnetic Resonance was established in February 2007 to facilitate the expansion of MRI as a mainstream modality for multi‐institutional measurements, including, among other things, multicenter trials. The goal of the Standards for Quantitative Magnetic Resonance committee was to provide a framework to ensure that quantitative measures derived from MR data are comparable over time, between subjects, between sites, and between vendors. This paper, written by members of the Standards for Quantitative Magnetic Resonance committee, reviews standardization attempts and then details the need, requirements, and implementation plan for a standard system phantom for quantitative MRI. In addition, application‐specific phantoms and implementation of quantitative MRI are reviewed. Magn Reson Med 79:48–61, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Multisite reliability and repeatability of an advanced brain MRI protocol

“…Reliability and repeatability in a multisite study may also be achieved by the inclusion of a phantom for site calibration. A recent review of the importance of the use of a phantom to calibrate data acquisition and analysis in longitudinal and/or in cross‐sectional multisite studies noted that phantoms that can deliver a quantitative reference or standard are of particular importance in multisite studies that make quantitative measurements, such as relaxation rates or lesion volumes . The use of such a phantom has been widely adopted by the Alzheimer's Disease Neuroimaging Initiative.…”

High‐Value MRI

“…Our field should standardize, and be quantitative, where possible . We should remove all geometric distortions, both those from nonlinear gradients (as is typically done) as well as those caused by frequency effects (eg, via B 0 maps).…”

Flexible and efficient optimization of quantitative sequences using automatic differentiation of Bloch simulations

“…The accuracy of the quantitative estimate depends on noise and the sequence's sensitivity to both confounding factors and the parameter of interest. The sequence's acquisition parameters must be carefully chosen for the parameter quantification to be accurate, and are often chosen to target a single or small number of tissues, or parameter ranges …”