While magnetic resonance imaging (MRI) has become more common for spotting lesions within the breast, different MRI machines at different hospitals can produce varying results that are difficult to compare against each other. To help standardize MRI imaging of breasts, researchers at the National Institute of Standards and Technology (NIST) have developed a phantom that replicates how breasts respond to MRI. The phantom will be useful for tuning MRI scanners and standardizing procedures, and also allowing researchers to compare results from different clinical studies that will use the new phantom for calibration.
The researchers tried the phantom using two MRI machines from different manufacturers and performed scans in three different configurations. The phantom device allowed the team to produce accurate, quantitative scans that could be compared for clinical applications.
More details about the new phantom according to NIST:
The phantom has a flexible, modular design. The soft silicone shell (15 by 12.5 centimeters) enables fitting to different MRI scanners. Internal components are made of rigid polycarbonate to ensure regular geometry. The phantom has two basic types of internal arrangements, which can be paired for MRI scans.
One unit is designed for conventional MRI scans based on magnetic properties of hydrogen atoms. This unit contains four layers of small plastic spheres filled with tissue mimics—corn syrup in water to represent fibroglandular tissue and grapeseed oil to represent fat. The spheres can be customized to meet special clinical needs. Potential future options include solutions that would mimic either benign cysts or tiny bits of calcium called microcalcifications, which can signal cancer.
The second phantom unit is designed for the newer technique of diffusion MRI, which measures the motion of water molecules within the breast. This unit contains plastic tubes filled with varying concentrations of a nontoxic polymer (polyvinylpyrrolidone), similar to NIST’s diffusion MRI phantom. The solutions are tuned to mimic the differing diffusion properties of malignant tumors versus benign tumors.
Study in Journal of Magnetic Resonance Imaging: Variability and bias assessment in breast ADC measurement across multiple systems…