Year: 2011
Type: article
Abstract: PURPOSE: In this study, the authors aim to develop a physical, tissue-mimicking phantom for quantitative evaluation of breast MRI protocols. The objective of this phantom is to address the need for improved standardization in breast MRI and provide a platform for evaluating the influence of image protocol parameters on lesion detection and discrimination. Quantitative comparisons between patient and phantom image properties are presented. METHODS: The phantom is constructed using a mixture of lard and egg whites, resulting in a random structure with separate adipose- and glandular-mimicking components. T1 and T2 relaxation times of the lard and egg components of the phantom were estimated at 1.5 T from inversion recovery and spin-echo scans, respectively, using maximum-likelihood methods. The image structure was examined quantitatively by calculating and comparing spatial covariance matrices of phantom and patient images. A static, enhancing lesion was introduced by creating a hollow mold with stereolithography and filling it with a gadolinium-doped water solution. RESULTS: Measured phantom relaxation values fall within 2 standard errors of human values from the literature and are reasonably stable over 9 months of testing. Comparison of the covariance matrices of phantom and patient data demonstrates that the phantom and patient data have similar image structure. Their covariance matrices are the same to within error bars in the anterior-posterior direction and to within about two error bars in the right-left direction. The signal from the phantom's adipose-mimicking material can be suppressed using active fat-suppression protocols. A static, enhancing lesion can also be included with the ability to change morphology and contrast agent concentration. CONCLUSIONS: The authors have constructed a phantom and demonstrated its ability to mimic human breast images in terms of key physical properties that are relevant to breast MRI. This phantom provides a platform for the optimization and standardization of breast MRI imaging protocols for lesion detection and characterization.
Source: Medical Physics
DOI: 10.1118/1.3533899
Institutions: United States Food and Drug Administration, Center for Devices and Radiological Health, University of Maryland, College Park, National Institutes of Health, National Institute of Neurological Disorders and Stroke, Division of Cancer Epidemiology and Genetics, Suez Canal University, Johns Hopkins University, Johns Hopkins Medicine
Language: English
Topic: MRI in cancer diagnosis
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
Funders: U.S. Department of Energy, National Institutes of Health, U.S. Food and Drug Administration, Oak Ridge Institute for Science and Education, National Heart, Lung, and Blood Institute, National Cancer Institute, National Institute of Neurological Disorders and Stroke, NIH Clinical Center, Office of Women's Health
OpenAlex ID: W2040565152