Related Experiment Video
Updated: May 12, 2026
10:23
A Machine-Vision Approach to Transmission Electron Microscopy Workflows, Results Analysis and Data Management
Published on: June 23, 2023
Generalized eMC implementation for Monte Carlo dose calculation of electron beams from different machine types
Michael K Fix1, Joanna Cygler, Daniel Frei
1Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, Switzerland. michael.fix@insel.ch
Physics in Medicine and Biology
|April 9, 2013
Summary
This study generalizes the electron Monte Carlo (eMC) algorithm for accurate dose calculations across Varian, Elekta, and Siemens linear accelerators. The enhanced eMC model achieves agreement within 2% or 2 mm for various beam parameters.
Area of Science:
- Medical Physics
- Radiation Oncology
- Computational Dosimetry
Background:
- The Eclipse treatment planning system's electron Monte Carlo (eMC) algorithm is Varian-specific.
- Applying this eMC to non-Varian machines limits dose calculation accuracy.
Purpose of the Study:
- To generalize the eMC algorithm for accurate electron beam dose calculations on Elekta and Siemens linear accelerators.
- To validate the generalized eMC model against established methods and experimental data.
Main Methods:
- Developed a generalized beam model incorporating multiple particle sources (electron, photon, edge, transmission, line).
- Improved secondary particle transport within the macro MC algorithm.
- Validated dose calculations against EGSnrc and experimental measurements in phantoms and water.
Main Results:
- The generalized eMC model demonstrated agreement within 2% or 2 mm compared to measured dose distributions.
- This accuracy was consistent across Varian, Elekta, and Siemens machines for various energies, applicator sizes, and SSDs.
Conclusions:
- The generalized eMC algorithm is suitable for accurate dose calculations on multiple linear accelerator platforms.
- This advancement expands the applicability of advanced Monte Carlo dose calculation methods in radiation therapy.
Related Concept Videos
01:26Applications of EMF Measurements
Electromotive force (EMF) measurements have a broad range of applications in various fields, including chemistry and physics. The electrochemical series, an arrangement of elements in order of their standard electrode potentials, can be determined through EMF measurements. Elements with lower standard potentials can reduce ions of elements with higher standard potentials.The standard cell potential, E°, allows for the calculation of the standard reaction Gibbs energy, ΔG°, and the equilibrium...
01:07Scanning Electron Microscopy
A scanning electron microscope (SEM) is used to study the surface features of a sample by using an electron beam that scans the sample surface in a two-dimensional manner. Typically, areas between ~1 centimeter to 5 micrometers in width can be imaged. SEM can be used to image bacteria, viruses, tissues as well as larger samples like insects. Conventional SEM gives a magnification ranging from 20X to 30,000X and spatial resolution of 50 to 100 nanometers.
Fundamental Principles
Accelerated...
Fundamental Principles
Accelerated...
01:25Multimachine Stability
Multimachine stability analysis is crucial for understanding the dynamics and stability of power systems with multiple synchronous machines. The objective is to solve the swing equations for a network of M machines connected to an N-bus power system.
In analyzing the system, the nodal equations represent the relationship between bus voltages, machine voltages, and machine currents. The nodal equation is given by:
In analyzing the system, the nodal equations represent the relationship between bus voltages, machine voltages, and machine currents. The nodal equation is given by:
01:25Overview of Electron Microscopy
The wavelengths of visible light ultimately limit the maximum theoretical resolution of images created by light microscopes. Most light microscopes can only magnify 1000X, and a few can magnify up to 1500X. Electrons, like electromagnetic radiation, can behave like waves, but with wavelengths of 0.005 nm, they produce significantly greater resolution up to 0.05 nm as compared to 500 nm for visible light. An electron microscope (EM) can create a sharp image that is magnified up to 2,000,000X.
01:15Transmission Electron Microscopy
In 1931, physicist Ernst Ruska—building on the idea that magnetic fields can direct an electron beam just as lenses can direct a beam of light in an optical microscope—developed the first prototype of the electron microscope. This development led to the development of the field of electron microscopy. In the transmission electron microscope (TEM), electrons are produced by a hot tungsten element and accelerated by a potential difference in an electron gun, which gives them up to 400 keV in...
01:20Maxwell-Boltzmann Distribution: Problem Solving
Individual molecules in a gas move in random directions, but a gas containing numerous molecules has a predictable distribution of molecular speeds, which is known as the Maxwell-Boltzmann distribution, f(v).
This distribution function f(v) is defined by saying that the expected number N (v1,v2) of particles with speeds between v1 and v2 is given by
This distribution function f(v) is defined by saying that the expected number N (v1,v2) of particles with speeds between v1 and v2 is given by