Development of a Novel Breast MRI Phantom for Quality Control

Magnetic Resonance Imaging

Wilmes

Aliu

et al. 2016

Purpose We present a breast phantom designed to enable quantitative assessment of measurements of T1 relaxation time, apparent diffusion coefficient (ADC), and other attributes of breast tissue, with long-term support from a national metrology institute. Materials and Methods A breast phantom was created with two independent, interchangeable units for diffusion and T1/T2 relaxation, each with flexible outer shells. The T1 unit was filled with corn syrup solution and grapeseed oil to mimic the relaxation behavior of fibroglandular, and fatty tissues respectively. The diffusion unit contains plastic tubes filled with aqueous solutions of polyvinylpyrrolidone (PVP) to modulate the apparent diffusion coefficient (ADC). The phantom was imaged at 1.5 T and 3.0 T using MRI scanners and common breast coils from multiple manufacturers to assess T1 and T2 relaxation time and ADC values. Results The fibroglandular mimic exhibited target T1 values on 1.5 T and 3.0 T clinical systems (25–75 percentile range: 1289 to 1400 ms and 1533 to 1845 ms respectively) across all bore temperatures. PVP solutions mimicked the range of ADC values from malignant tumors to normal breast tissue (40 % PVP median: 633 × 10−6 mm2/s to 0 % PVP median: 2231 × 10−6 mm2/s) at temperatures 17 °C to 24 °C. The interchangeable phantom units allowed both the diffusion and T1/T2 units to be tested on the left and right sides of the coil to assess any variation. Conclusions This phantom enables T1 and ADC measurements, fits in a variety of clinical breast coils, and can serve as a quality control tool to facilitate the standardization of quantitative measurements for breast MRI.

Section: Discussionmentioning

confidence: 89%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Design of a breast phantom for quantitative MRI

Magnetic Resonance Imaging

Wilmes

Aliu

et al. 2016

“…A breast phantom is a quality control device that can be used to quantify measurement variability due to system hardware, software, or imaging sequence. A breast phantom was introduced that is compatible with multiple coil styles, contains diffusion mimics for fat and healthy fibroglandular tissue, benign and malignant tumor tissue, and has an anatomically appropriate design, 9 distinguishing it from previous breast phantoms that were compatible with only one coil, 10 lacked diffusion mimics, 11 or lacked fat tissue mimics. 12 The goal of this study is to assess the ability of this breast phantom to serve as a quality control device for comparison of ADC data across scanner-coil-sequence combinations and repeated scanning (e.g., as would be required in a multisystem study or clinical trial).…”

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confidence: 99%

Variability and bias assessment in breast ADC measurement across multiple systems

Magnetic Resonance Imaging

Peskin

Wilmes

et al. 2016

Purpose To assess the ability of a recent, anatomically-designed breast phantom incorporating T1 and diffusion elements to serve as a quality control device for quantitative comparison of apparent diffusion coefficient (ADC) measurements calculated from diffusion-weighted MRI (DWI) within and across MRI systems. Materials and Methods A bilateral breast phantom incorporating multiple T1 and diffusion tissue mimics and a geometric distortion array was imaged with DWI on 1.5 T and 3.0 T scanners from two different manufacturers, using three different breast coils (three configurations total). Multiple measurements were acquired to assess the bias and variability of different diffusion weighted single-shot echo-planar imaging (SS-EPI) sequences on the scanner-coil systems. Results The repeatability of ADC measurements was mixed: the standard deviation relative to baseline across scanner-coil-sequences ranged from low variability (0.47, 95% Confidence Interval (CI): 0.22–1.00) to high variability (1.69, 95% CI: 0.17–17.26), depending on material, with the lowest and highest variability from the same scanner-coil-sequence. Assessment of image distortion showed that Right/Left measurements of the geometric distortion array were 1 to 16 % larger on the left coil side compared to the right coil side independent of scanner-coil systems, diffusion weighting, and phase-encoding direction. Conclusions This breast phantom can be used to measure scanner-coil-sequence bias and variability for DWI. When establishing a multi-system study, this breast phantom may be used to minimize protocol differences (e.g. due to available sequences or shimming technique), to correct for bias that cannot be minimized, and to weigh results from each system depending on respective variability.

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

Magnetic Resonance in Med

Ainslie

Barker

et al. 2017

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134

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.