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Vesna Spasić-Jokić

Publications and source records attributed to Vesna Spasić-Jokić.

4 recordsLinked to original sources
PubMed2005

The Monte Carlo SRNA-VOX code for 3D proton dose distribution in voxelized geometry using CT data.

This paper describes the application of the SRNA Monte Carlo package for proton transport simulations in complex geometry and different material compositions. The SRNA package was developed for 3D dose distribution calculation in proton therapy and dosimetry and it was based on the theory of multiple scattering. The decay of proton induced compound nuclei was simulated by the Russian MSDM model and our own using ICRU 63 data. The developed package consists of two codes: the SRNA-2KG, which simulates proton transport in combinatorial geometry and the SRNA-VOX, which uses the voxelized geometry using the CT data and conversion of the Hounsfield's data to tissue elemental composition. Transition probabilities for both codes are prepared by the SRNADAT code. The simulation of the proton beam characterization by multi-layer Faraday cup, spatial distribution of positron emitters obtained by the SRNA-2KG code and intercomparison of computational codes in radiation dosimetry, indicate immediate application of the Monte Carlo techniques in clinical practice. In this paper, we briefly present the physical model implemented in the SRNA package, the ISTAR proton dose planning software, as well as the results of the numerical experiments with proton beams to obtain 3D dose distribution in the eye and breast tumour.

Algorithms↗
PubMedDate not supplied

[Occupational exposure to ionizing radiation and the occurrence of cataract].

Radiation cataract is one of ensuing effects of ionizing radiation, since its threshold dose under which it does not occur, and above which it shows dose dependency, has been observed. Clinical course of radiation cataract is identical for all the types of ionizing radiation and is very typical. Minimal dose for progressive cataract formation is determined by the type of radiation, i.e., its relative biological efficacy, dose, and the duration of the exposure period. Theoretically, threshold dose existence does not exclude the incidence of cataract formation under significantly smaller doses, as well. The aim of this study was to analyze the incidence of cataract formation among the medical staff professionally exposed to ionizing radiation. Neither of the diagnosed cataracts had typical morphology, nor was the correlation established between the dose, exposure time, and the cataract formation. All the diagnosed cataracts were described as premature, and therefore ionizing radiation was considered as a co-factor in premature cataract formation in the examined groups.

Adult↗