Table 1. fMRI QA phantoms.
| References | Type | Description | QA measurements |
|---|---|---|---|
| (32) | Liquid phantom | The phantom body had five layers with 14×14 square cells (5×5×10 mm3) in each layer. The phantom was built from MRI neutral material and filled with different solutions of CuSO4 water solution. The phantom body was placed on a moveable platform to simulate translations and rotations | Spin-history artifacts |
| (43) | Liquid phantom | The cylindrical phantom consisted of multiple axial plates with hollow spheres in each plate. The hollow spheres are connected by drilled capillaries. The phantom was made of acrylic and filled with distilled water | Geometric distortions |
| (7) | Liquid phantom | A spherical phantom filled with CuSO4 solution in a loading annulus | SNR, SGR, PSC |
| (15-17,20) | Agar phantom | FBIRN’s QA phantom was a 17.5-cm-diameter spherical container filled with agar gel, 0.5% NaCl, 21.8 mmol/L NiCl2, providing T1 and T2 comparable to those in the gray matter at 1.5 T fMRI system | SNR, SFNR, PSF |
| (8) | Type I | A cylinder was divided into 8 wedge-shaped compartments. The compartments were filled with 1.4% or 1.6% agar gel. The cylinder was connected to a handle for rotational control | CNR |
| (9) | Type I | The Phantom made from PMMA had two cylinders. The inner cylinder had two compartments filled with 2.44% and 2.21% agarose, acting as “active” and “baseline” state | PSC |
| (10) | Type I | The phantom had two cylinders. The outer cylinder was filled with 2.27% agarose. The inner cylinder had four compartments filled with 2.21 and 2.27% agarose gels | Signal fluctuation sensitivity |
| (11) | Type II | SmartPhantom had two cylinders. The inner cylinder holding agarose gel was surrounded by two conductor loops forming a quadrature coil. The outer cylinder, also contained agarose gel. The inner cylinder served as the ROI, and the outer cylinder provided a signal background | SNR, CNR; comparison of processing tools including BrainVoyager, FSL, and SPM |
| (12) | Type II | The phantom consisted of a polymethylacrylate tube filled with rapeseed oil. The wounding lacquer-insulated wire was fixed along the central axis of the phantom. The wire was attached to the electronic equipment via a copper pipe | scanner calibration |
| (13) | Type II | Applied magnetic inhomogeneity phantom included a polycarbonate container filled with Gd-doped water. The container was supported by polyurethane foam; the foam had a circular perforation with cylindrical coils attached | SNR |
| (14) | Type II | The phantom consisted of a geometric grid, eight vials with aqueous solutions of 2.4% gelatin and different concentrations CuSO4, and a cylindrical electrical cell filled with propylene carbonate, all surrounded by water. An electrical circuit board was connected to the electrical cell to interface the phantom during the fMRI scan | – |
fMRI, functional magnetic resonance imaging; QA, quality assurance; SNR, signal-to-noise ratio; SGR, signal-to-ghost ratio; PSC, percentage signal change; PSF, percent signal fluctuation; CNR, contrast-to-noise ratio; SFNR, signal-to-fluctuation-noise ratio; ROI, region-of-interest; SPM, Statistical Parametric Mapping; FSL, FMRIB Software Library.