PHOTON BEAM DOSE CALCULATIONS USING ELECTRON DENSITY FROM CT NUMBER
نویسندگان
چکیده
منابع مشابه
Assessing the effect of electron density in photon dose calculations.
Photon dose calculation algorithms (such as the pencil beam and collapsed cone, CC) model the attenuation of a primary photon beam in media other than water, by using pathlength scaling based on the relative mass density of the media to water. In this study, we assess if differences in the electron density between the water and media, with different atomic composition, can influence the accurac...
متن کاملTolerance levels of CT number to electron density table for photon beam in radiotherapy treatment planning system
The accuracy of computed tomography number to electron density (CT-ED) calibration is a key component for dose calculations in an inhomogeneous medium. In a previous work, it was shown that the tolerance levels of CT-ED calibration became stricter with an increase in tissue thickness and decrease in the effective energy of a photon beam. For the last decade, a low effective energy photon beam (...
متن کاملMeasurements of Photon Beam Flattening Filter Using an Anisotropic Analytical Algorithm and Electron Beam Employing Electron Monte Carlo
Introduction: This study aimed to report the measurement of photon and electron beams to configure the Analytical Anisotropic Algorithm and Electron Monte Carlo used in clinical treatment. Material and Methods: All measurements were performed in a large water phantom using a 3-dimensional scanning system (PTW, Germany). ...
متن کاملTissue Density Mapping of Cone Beam CT Images for Accurate Dose Calculations
Purpose: To improve the accuracy in megavoltage photon beam dose calculation in CBCT-based radiation treatment (RT) plans, using a kilovoltage cone-beam computed tomography (CBCT)-todensity-step (CBCT-SF) function. Materials and Methods: The CBCT-SF table is constructed from differential histograms of the voxel values of CBCT and Fan-beam CT (FBCT). From the CBCT histograms, frequency peaks rep...
متن کاملLateral electron transport in FFT photon dose calculations.
Previously published FFT dose calculations and their verifications have been performed for field sizes greater than 10 cm x 10 cm with photon energies up to 18 MV [Zhu and Boyer, Phys. Med. Biol. 35, 351-368 (1990)]. With a smaller field size at megavoltage energies, lateral electronic disequilibrium exists in low density inhomogeneities which is not handled properly by the FFT calculations. In...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Japanese Journal of Radiological Technology
سال: 1981
ISSN: 0369-4305,1881-4883
DOI: 10.6009/jjrt.kj00001365382