A solid plastic phantom has been developed with optical properties that closely match those of human breast tissue at near-IR wavelengths. The phantom is a 54-mm-thick slab containing four small cylinders of contrasting scatter and absorption. A detailed description of the phantom is followed by an account of an attempt to image the phantom by a time-resolved imaging technique. Images generated...

The use of electronic portal imaging devices (EPIDs) is a promising method for the dosimetric verification of external beam, megavoltage radiation therapy-both pretreatment and in vivo. In this study, a previously developed EPID back-projection algorithm was modified for IMRT techniques and applied to an amorphous silicon EPID. By using this back-projection algorithm, two-dimensional dose distr...

Reconstruction algorithms for imaging fluorescence in near infrared ranges usually normalize fluorescence light with respect to excitation light. Using this approach, we investigated the influence of absorption and scattering heterogeneities on quantification accuracy when assuming a homogeneous model and explored possible reconstruction improvements by using a heterogeneous model. To do so, we...

PURPOSE To propose a method to reduce the slab boundary artifacts in three-dimensional multislab diffusion MRI. METHODS Bloch simulation is used to investigate the effects of multiple factors on slab boundary artifacts, including characterization of residual errors on diffusion quantification. A nonlinear inversion method is proposed to simultaneously estimate the slab profile and the underly...

introduction low dose rate brachytherapy sources have been widely used for interstitial implants in tumor sites, particularly in prostate. dosimetric characteristics of a new irseed 125i brachytherapy source have been determined using the lif thermoluminescent dosimeter (tld) chips. materials and methods dose rate constant, radial dose function, and anisotropy function around the irseed 125i so...

INTRODUCTION Wide agreement has been reached among the main Bodies and Organizations involved in standardization of radiation protection to define as operational quantity for individual monitoring of external exposure, the personal dose equivalent, Hp(d) (1,2,3). However, as Hp(d) is defined in the human body, it is not a measurable quantity. In practice, it has to be estimated from the indicat...

Background: The advantages of proton beam in radiation therapy- like small lateral scattering as well as absence of exit dose tail in the organs which are after the tumor- make it capable of delivering more treatment doses to the target and much lesser to the critical tissues near it. Materials and Methods: In this study, the Monte Carlo MCNPX code has been used to simulate a slab head phantom ...

BACKGROUND Tumor-Treating Fields (TTFields) are a novel treatment strategy for glioblastoma (GBM) that is approved for the use concomitantly to adjuvant chemotherapy. Preclinical data suggest a synergistic interaction of TTFields and radiotherapy (RT). However, the dosimetric uncertainties caused by the highly dense arrays have led to caution of applying the TTF setup during RT. METHODS In a ...