introduction radioactive materials naturally exist in the world. indeed, approximately 82% of human-absorbed radiation doses, which are out of human control, arise from natural sources of radiation including cosmic, terrestrial, and exposure through inhalation or ingestion. thus, the aim of the present study was to estimate health risk, as well as the effective and organ doses from naturally oc...

Background: Prediction of the absorbed dose in irradiated volume plays an important role in the outcome of radiotherapy. Application of small fields for radiotherapy of thorax makes the dose calculation process inaccurate due to the existence of electronic disequilibrium and intrinsic deficiencies in dose calculation algorithms. To study the lung absorbed dose in radiotherapy with smal...

Introduction: Radiotherapy is an effective modality to treat esophageal carcinoma. Due to various inhomogenous tissues with a variety of physical and radiological properties which can cause uncertainty in accurate dose calculations in radiation therapy, accuracy of TPS is very important. The aim of this study was to quantify dose calculation accuracy of CoreplanTM TPS in an inh...

The knowledge of the absorbed radiation dose is essential in order to interpret the results of animal experiments with chronic ingestion of radionuclides by rodents. In order to evaluate this absorbed dose, we applied the dose conversion factors proposed by ICRP publication 108 to mouse chronic ingestion experiments with 20 kBq.L-1 137Csor 90Sr-contaminated water. The results indicated that who...

Potassium dithionate EPR dosimetry for determination of absorbed dose and LET distributions in different radiation qualities. Abstract With an increasing interest in using protons and light ions for radiation therapy there is a need for possibilities to simultaneously determine both absorbed dose (D) and linear energy transfer, LET, (LΔ). Potassium dithionate (K2S2O6) tablets were irradiated in...

introduction: during radiotherapy, high accuracy in the dose delivery is required because there is a strong  relationship between the absorbed dose, local tumor control and particularly the normal tissue damage. in  many institutions, in vivo dosimetry using diodes is performed to check the actual dose delivered. in general,  the uncertainty in the dose delivered should fall within  ± 5% of the...

Background and Objective: The most common intravascular brachytherapy sources include 32P, 188Re, 106Rh and 90Sr/90Y. In this research, skin absorbed dose for different covering materials in dealing with these sources were evaluated and the best covering material for skin protection and reduction of absorbed dose by radiation staff was recognized and recommended.Method: Four materials including...

Response and toxicity prediction is essential to rational implementation of cancer therapy. The biologic effects of radionuclide therapy are mediated via a well-defined physical quantity, the absorbed dose, which is defined as the energy absorbed per unit mass of tissue. The concepts, basic definitions, and different approaches to the clinical implementation of absorbed dose estimation are revi...

Radiochromic film with a dye incorporated into the radiation sensitive layer [Gafchromic EBT2, Ashland, Inc.] may be digitized by a color transparency scanner, digitally processed, and calibrated so that a digital image in units of radiation absorbed dose is obtained. A transformation from raw scanner values to dose values was developed based upon a principal component analysis of the optical d...

Background: Annual patient effective dose equivalent can be considered as a quantitative physical parameter describing the activities performed in each nuclear medicine department. Annual staff dose equivalent could be also considered as a parameter describing the amount of radiation risk for performing the activities. We calculated the staff to patient dose equivalent ratio to be used as a phy...