*Corresponding author: Dr. Tayyeb Allahverdi Pourfallah, Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran. Fax: +98 21 88973653 E-mail: [email protected] Background: Polymer gel dosimetry is still the only dosimetry method for direct measuring of threedimensional dose distributions. MRI Polymer gel dosimeters are tissue equi...

In the past the operational quantity H(p)(3) has been defined for calibration purposes in a slab phantom. Recently, an additional phantom in the form of a cylinder was suggested for eye lens dosimetry as a cylinder much better approximates the shape of a head than a slab. Therefore, this work investigates whether the quantity H(p)(3), when defined in the respective calibration phantom, adequate...

Spatial reproduction in a conventional stereophonic audio system (e.g., stereo or 5.1 surround) works in a small area known as the ”sweet spot“. If the listener changes his position, the phantom source moves in the same direction and finally collapses into the nearer loudspeaker. A play-back system that adjusts the loudspeaker signals depending only on the listener’s position in real-time was e...

PURPOSE To evaluate the effect of objects moving outside the field of view on functional MR imaging. METHODS Echo-Planar image sequences were acquired in the sagittal plane of a stationary phantom or of the head of a volunteer subject while a second phantom was moved periodically outside the field of view. The signal intensity changes in each pixel within the field of view were measured. RE...

Radiotherapy treatment planning integrating positron emission tomography (PET) and computerized tomography (CT) is rapidly gaining acceptance in the clinical setting. Although hybrid systems are available, often the planning CT is acquired on a dedicated system separate from the PET scanner. A limiting factor to using PET data becomes the accuracy of the CT/PET registration. In this work, we us...

Introduction: Total Skin Electron Therapy (TSET) and Total Body Irradiation (TBI) are kinds of treatment which use electron and photon beams to treat special types of cancers. The aim of these techniques are to deliver uniform dose to the entire skin while minimizing delivered dose to organs at risk. To check the homogeneity of dose delivery in TBI and TSET, using a humanoid ph...

Purpose Functional magnetic resonance imaging (fMRI) during infancy poses challenges due to practical, methodological, and analytical considerations. The aim of this study was implement a hardware-related approach increase subject compliance for fMRI involving awake infants. To accomplish this, we designed, constructed, evaluated an adaptive 32-channel array coil. Methods allow with close-fitti...