The equivalent dose limit for the eye lens for occupational exposure recommended by the ICRP has been reduced to 20 mSv y(-1) averaged over defined periods of 5 y, with no single year exceeding 50 mSv. The compliance with this new requirement could not be easy in some workplace such as interventional radiology and cardiology. The aim of this study is to evaluate different possible approaches in...

background : in spite of clinically useful photon and electron beams, high energy linacs produce secondary particles such as neutrons (photo-neutron production). neutrons have important roles during treatment with high energy photons in terms of protection and dose escalation. in this project, neutron dose equivalent of 18 mv varian accelerators is calculated by tld600 and tld700. materials and...

Background: In nuclear medicine application often it is required to use computational methods for evaluation of organ absorbed dose. Monte Carlo simulation and phantoms have been used in many works before. The shape, size and volume in organs are varied, and this variation will produce error in dose calculation if no correction is applied. Materials and Methods: A computational framewo...

Target audience: Radiofrequency (RF) engineers, anyone interested in high field RF coils, parallel transmit or high field brain imaging. Introduction: Electric dipole antennas are seeing increasing use for 7T MR imaging. They differ from conventional surface coil loops in many ways. With 8 elements surrounding a body sized tissue equivalent phantom and array of dipole antennas can achieve highe...

A novel IMRT phantom was designed and fabricated using Acrylonitrile Butadiene Styrene (ABS) plastic. Physical properties of ABS plastic related to radiation interaction and dosimetry were compared with commonly available phantom materials for dose measurements in radiotherapy. The ABS IMRT phantom has provisions to hold various types of detectors such as ion chambers, radiographic/radiochromic...

introduction the gamma knife system is designed solely for non-invasive treatment of brain disorders, and it benefits from stereotactic surgical techniques. dose calculations required in the system are performed by gammaplan code; in this code, brain tissue is considered uniform. in the present study, we evaluated the effect of gamma knife system on the obtained dose through simulating a real h...

Radiation doses to tissues and organs were measured using the anthropomorphic phantom as an equivalent to the human body. When high-energy X-rays are externally applied to treat laryngeal cancer, the absorbed dose at the laryngeal lumen is lower than given dose because of air space, which it should pass through, before reaching the lesion. Specially, in case of high-energy X-rays, the loss of d...

Introduction: This study aimed to establish the conversion factors to normalize the output dose of volumetric computed tomography dose index (CTDIvol) to the patient dose (i.e. size-specific dose estimate (SSDE)) for various phantom diameters and tube voltages. Material and Methods: In-house cylindrical acrylic phantoms with physical diameter...

introduction accurate estimation of the absorbed dose in radiosensitive organs, located away from the target volume during radiotherapy, is one of the main reasons for the development of reference phantoms. the international commission on radiological protection (icrp) reference phantoms can provide a more realistic view of the human anatomy in comparison with the previously used mathematical p...

Microdosimetric single event spectra as a function of depth in a phantom for the 290 MeV/nucleon therapeutic carbon beam at HIMAC were measured by using a tissue equivalent proportional counter (TEPC). Two types of geometries were used: one is a fragment particle identification measurement (PID-mode) with time of flight (TOF) method without a backward phantom, and the other is an in-phantom mea...