A prototype scanning-laser fan beam optical CT scanner is reported which is capable of high resolution, large volume dosimetry with reasonable scan time. An acylindrical, asymmetric aquarium design is presented which serves to 1) generate parallel-beam scan geometry, 2) focus light towards a small acceptance angle detector, and 3) avoid interference fringe-related artifacts. Preliminary experim...

Two specially designed plastic/aluminum phantoms positioned thermoluminescent dosimeters (TLDs) at the right and left breast location of an anthrophomorophic chest torso. Imaging was performed on a spiral CT for a Volume of the chest phantom through the breast area for a noncontiguous (pitch 1.5) helical chest scan. Conventional pencil beam ionization chamber measurements were made at the same ...

This paper reviews the principles of Electrical Impedance Tomography (EIT), different types of current patterns and reconstruction algorithms to assess its potential in medical imaging. A current injection pattern in EIT has its own current distribution profile within the subject under test. Hence, different current patterns have different sensitivity, spatial resolution and distinguishability....

We used multiple optical wavelengths to study ultrasound-modulated optical tomography (UOT) in tissue phantoms. By using intense acoustic bursts and a CCD camera-based speckle contrast detection technique, we observed variations of the ultrasound-modulated signal at various optical absorptions. The experimental variations were found to be highly correlated with predictions from Monte Carlo simu...

In proton density-weighted (PDW) MR imaging, the patterns of signal intensity vary depending on the imaged material, and change with the flip angle (FA) applied to the imaged material. The correlation between the pre-determined FA and the actual FA applied to imaged objects was investigated using 4 types of phantoms having different dielectric properties. PDW images were acquired using the spin...

irk J. Faber niversity of Amsterdam cademic Medical Center epartment of Biomedical Engineering and Physics and pththalmology Department msterdam, 1100 DE Netherlands Abstract. Current innovations in optical imaging, measurement techniques, and data analysis algorithms express the need for reliable testing and comparison methods. We present the design and characterization of silicone elastomer-b...

Purpose The use of three-dimensional (3D) printing to develop custom phantoms for dosimetric studies in radiotherapy is increasing. process allows production designed evaluated specific geometries, patients, or patient groups with a defining feature. ability print bone-equivalent has, however, proved challenging. purpose this work was 3D series three similar spine containing no surgical implant...

The goal of this study was to examine the impact using additional aluminum (Al) and copper (Cu) filters on radiation dose during adult chest x-ray examination. Adult phantoms without with different slabs animal fat were used for simulating underweight, overweight, obese patients, respectively. Phantoms examined various levels extra Al Cu filtering over a range exposure parameters. A area produc...

Radiation dose calculation using models of the human anatomy has been a subject of great interest to radiation protection, medical imaging, and radiotherapy. However, early pioneers of this field did not foresee the exponential growth of research activity as observed today. This review article walks the reader through the history of the research and development in this field of study which star...

The possibility to directly and non-invasively localize neuronal activities in the human brain, as for instance by performing current imaging (NCI) via magnetic resonance (MRI), would be a breakthrough neuroscience. In order assess feasibility of 3-dimensional (3D) NCI, comprehensive computational physical phantom experiments using low-noise ultra-low-field (ULF) MRI technology were performed t...