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Medical Imaging Phantom Lending Library


Coming October 2020!

As part of the MRI Biomarker Measurement Service, traceable magnetic resonance imaging (MRI) phantoms will be available for loan at a minimal cost, plus shipping. Initially, 2 copies of the MRI system phantom developed by NIST and the international Society of Magnetic Resonance in Medicine (ISMRM) and 2 copies of the MRI diffusion phantom developed by NIST, the Radiological Society of North America (RSNA), and the National Institutes of Health (NIH) will be available for check out. Analysis code, sample images, and references can be found at Checkout services can be found at, type in “MRI” or “phantom” in the product search window. The phantoms come with NIST calibration reports and operation instructions.


MRI system

The MRI system phantom showing major components including fiducial array, T1, T2, and proton density arrays, resolution insets, and slice profile inset.

Phantoms are calibration objects that can be used to assess the accuracy, stability, and comparability of medical imaging systems. The NIST/ISMRM MRI system phantom can be used to assess scanner geometric distortion, image uniformity, signal to noise ratio (SNR), resolution, slice profile and thickness, RF-field nonuniformity, and accurate of proton relaxation times (T1, T2) and proton density measurements.

The water self-diffusion coefficient can be an important biomarker of tissue health in both neural and cancer imaging. The diffusion phantom contains several polymer vials with well-defined isotropic water self-diffusion coefficients to determine the accuracy of MRI-based measurements. To obtain precise values for water diffusion, the phantom temperature must be precisely controlled or measured. The phantom can either be operated at 0 C by adding ice, or can be used at typical bore temperatures using the embedded MRI readable thermometer.

MRI diffusion phantom
MRI diffusion phantom at 0 C, with ice water fill, showing vials with different diffusion coefficients, data and fits, and measured values spanning the range of 0.2 to 1.1 x 10-3 mm2/s.
Created July 27, 2020, Updated July 28, 2020