Introduction: Spatial dose distribution around the radionuclides sources is required for optimized treatment planning in radioimmunotherapy. At present, the main source of data for cellular dosimetry is the s-values provided by MIRD. However, the MIRD s-values have been calculated based on analytical formula in which no electrons straggling is taken to account. In this study, we used Geant4-DNA...

The internal dosimetry schema of the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine has provided a broad framework for assessment of the absorbed dose to whole organs, tissue subregions, voxelized tissue structures, and individual cellular compartments for use in both diagnostic and therapeutic nuclear medicine. The schema was originally published in 1968, r...

BACKGROUND PET/CT has recently been shown to be a viable alternative to traditional post-infusion imaging methods providing good quality images of 90Y-laden microspheres after selective internal radiation therapy (SIRT). In the present paper, first we assessed the quantitative accuracy of 90Y-PET using an anthropomorphic phantom provided with lungs, liver, spine, and a cylindrical homemade lesi...

A dose-response study was performed in adult rats to select an optimal stable potassium iodide (KI) dose which could be implemented in repeated prophylaxis, in case of prolonged exposure to radioactive iodine. Increasing doses of KI were given orally to rats 1 hour before internal exposure simulated by I-125 injection. I-125 incorporation in the thyroid was measured by γ-spectrometry, and KI pr...

UNLABELLED Ex vivo autoradiographs of healthy kidney tissue from patients who received (111)In-DTPA-octreotide (DTPA is diethylenetriaminepentaacetic acid) before nephrectomy showed very heterogeneous radioactivity patterns in the kidneys. The consequences of the reported inhomogeneities have been evaluated for radionuclide therapy with (90)Y- DOTA-Tyr(3)-octreotide (DOTA is 1,4,7,10-tetraazacy...

introduction: spatial dose distribution around the radionuclides sources is required for optimized treatment planning in radioimmunotherapy. at present, the main source of data for cellular dosimetry is the s-values provided by mird. however, the mird s-values have been calculated based on analytical formula in which no electrons straggling is taken to account. in this study, we used geant4-dna...

MCNP is widely used Monte Carlo program in reactor and nuclear physics. However, an option of simulating electrons was added into the code a few years ago. With this extension MCNP became a code, potentially applicable for applications in medical physics. In 1997, a new version of the code, named MCNP4B was released, which contains several improvements in electron transport modelling. To test s...

In order to evaluate internal dose, MIRD system was proposed by Society of Nuclear Medicine in 1976. MIRDOSE3 computer software based on this concept is currently the most frequently used tool to calculate the organ dose in nuclear medicine community. Unfortunately it uses fixed anthropomorphic phantoms, so the geometric parameters of organs are short of individual characteristics. Although the...

For the scope of risk assessment in protection against ionising radiation (occupational, environmental and medical) it is necessary to determine the radiation dose to specific body organs and tissues. For this purpose, a series of models of the human body were designed in the past, together with computer codes simulating the radiation transport and energy deposition in the body. Most of the com...

The dose distribution inside the Gamma Cobalt irradiation therapy unit at Egyptian Atomic Energy Authority (EAEA) was determined both experimentally and theoretically. MCNP computer code, based on Monte Carlo method, was used to model the unit and calculate the dose distributions in both normal and emergency situation of the unit. The dose distribution inside the unit was also measured during t...