title: An anthropomorphic phantom for quantitative evaluation of breast MRI.
abstract: OBJECTIVE
  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.
authors: Division of Imaging and Applied Mathematics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, USA. melanie.freed@fda.hhs.gov
authors: Melanie
authors: M
authors: Freed
authors: Jacco A
authors: JA
authors: de Zwart
authors: Jennifer T
authors: JT
authors: Loud
authors: Riham H
authors: RH
authors: El Khouli
authors: Kyle J
authors: KJ
authors: Myers
authors: Mark H
authors: MH
authors: Greene
authors: Jeff H
authors: JH
authors: Duyn
authors: Aldo
authors: A
authors: Badano
mesh_terms: D000273:Adipose Tissue / Q000166:cytology / Q000473:pathology; D001940:Breast / Q000033:anatomy & histology / Q000166:cytology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D019047:Phantoms, Imaging