Introduction: Clusters of calcium oxalate (CaOX) and hydroxyapatite (CaHA) crystals are generally associated with benign and malignant breast lesions, respectively. Such microcalcifications (microcalcs) are useful radiological indicators of early-stage, breast carcinoma. This study tests the detectability of these microcalcs by MRI, compared to conventional x-ray imaging methods, for potential ...

Low frequency drift (0.0-0.015 Hz) has often been reported in time series fMRI data. This drift has often been attributed to physiological noise or subject motion, but no studies have been done to test this assumption. Time series T*2-weighted volumes were acquired on two clinical 1.5 T MRI systems using spiral and EPI readout gradients from cadavers, a normal volunteer, and nonhomogeneous and ...

Citation: Ginsburger K, Poupon F, Beaujoin J, Estournet D, Matuschke F, Mangin J-F, Axer M and Poupon C (2018) Improving the Realism of White Matter Numerical Phantoms: A Step toward a Better Understanding of the Influence of Structural Disorders in Diffusion MRI. Front. Phys. 6:12. doi: 10.3389/fphy.2018.00012 Improving the Realism of White Matter Numerical Phantoms: A Step toward a Better Und...

A broadband coax technique developed by us for the measurement of dielectric properties of biological substances upto at least 20 GHz, is discussed. For water-based materials such as blood or muscle substitute phantoms, a 0.047 inch size probe is essential to minimize errors due to radiation. The data indicate the importance of the dielectric volume of the constituents, and enable tailoring of ...

A numerical study of the induced fields and specific absorption rate (SAR) in anatomical phantoms exposed to the radiofrequency (RF) fields of magnetic resonance (MR) scanners was conducted using the finite difference time domain (FDTD) method at 64MHz and 128MHz. Three phantoms including two adults and one child were used. The study revealed inconsistencies between the MRI safety standards and...

background: the heterogeneous composition of the human body presents numerous tissue types and cavities with widely differing radiologic properties. the aim of the present work was to develop a low cost homogeneous and heterogeneous phantom and the absorbed dose were measured by ionization chamber for different radiotherapy treatment techniques and compared with treatment planning system absorb...

Background: The heterogeneous composition of the human body presents numerous tissue types and cavities with widely differing radiologic properties. The aim of the present work was to develop a low cost homogeneous and heterogeneous phantom and the absorbed dose were measured by ionization chamber for different radiotherapy treatment techniques and compared with treatment planning syst...

Highly hydrophilic hollow polycaprolactone (PCL) microfibres were developed as building elements to create tissue-mimicking test objects (phantoms) for validation of diffusion magnetic resonance imaging (MRI). These microfibres were fabricated by the co-electrospinning of PCL-polysiloxane-based surfactant (PSi) mixture as shell and polyethylene oxide as core. The addition of PSi had a significa...

Background Myocardial T1 and extracellular volume (ECV) estimates have applications in a range of myocardial diseases. Factors responsible for systematic inaccuracies in T1 mapping are beginning to be known but little is known about its delivery at ‘health-care system’ scale and there is no global quality assurance (QA) system. Agarose phantoms are common in MRI and nickel ions preferred for lo...

New mathematical phantoms based on medical image data are allowing evaluation of internal and external dose calculations using better anatomic realism and inclusion of organs that were not previously defined. In this work, we show preliminary data for new radiation dose estimates for radiopharmaceuticals and CT examinations, using Monte Carlo radiation simulation routines developed in the Geant...