Photon fluence and dose estimation in computed tomography using a discrete ordinates Boltzmann solver

  title={Photon fluence and dose estimation in computed tomography using a discrete ordinates Boltzmann solver},
  author={Edward Thomas Norris and Xin Liu},
  journal={Scientific Reports},
In this study, cone-beam single projection and axial CT scans are modeled with a software package—DOCTORS, which solves the linear Boltzmann equation using the discrete ordinates method. Phantoms include a uniform 35 cm diameter water cylinder and a non-uniform abdomen phantom. Series simulations were performed with different simulation parameters, including the number of quadrature angles, the order of Legendre polynomial expansions, and coarse and fine mesh grid. Monte Carlo simulations were… 



Deterministic absorbed dose estimation in computed tomography using a discrete ordinates method.

The simulation results showed that the deterministic method can be effectively used to estimate the absorbed dose in a CTDI phantom, and the primary benefit of the discrete ordinates method lies in its rapid computation speed.

Deterministic photon transport calculations in general geometry for external beam radiation therapy.

It is concluded that the deterministic method is a rigorous, first-principles approach that could provide a superior alternative to Monte Carlo calculations for some types of problems, however additional development is needed to provide capability for 3D electron transport calculations.

A Monte Carlo-based method to estimate radiation dose from spiral CT: from phantom testing to patient-specific models.

A method to estimate the relative and absolute absorbed radiation dose from axial and spiral CT scans using a Monte Carlo approach is developed and test and application to patient models was shown to be feasible.

A CT-based Monte Carlo simulation tool for dosimetry planning and analysis.

A graphical user interface has been developed that automatically sets up the MCNP4A geometry and radiation source requirements for a three-dimensional Monte Carlo simulation using computed tomography data.

Validation of a Monte Carlo tool for patient-specific dose simulations in multi-slice computed tomography

Three-dimensional dose distributions can be accurately calculated with the MC tool for arbitrary scanners and protocols including tube current modulation schemes, and the tool has been extended to further scanners and to flat-detector CT.

Monte Carlo assessment of computed tomography dose to tissue adjacent to the scanned volume.

A series of tables normalized at 100 milliampere seconds were produced which allow the straight-forward assessment of dose within and peripheral to the CT scanned volume and should be useful for medical physicists and radiologists in the estimation of dose to sites beyond the edge of theCT scanned volume.

A Monte Carlo based method to estimate radiation dose from multidetector CT (MDCT): cylindrical and anthropomorphic phantoms.

The verification of Monte Carlo based methods for estimating radiation dose in computed tomography (CT) exams beyond a single CT scanner to a multidetector CT (MDCT) scanner is extended, and the ability to extend models from a single detector scanner using cylindrical phantoms to an MDCT scanner using both cylINDrical and anthropomorphic phantom is demonstrated.

Demonstration of three-dimensional deterministic radiation transport theory dose distribution analysis for boron neutron capture therapy.

An application of a deterministic method to analytically simulate BNCT treatment of a canine head phantom using the epithermal neutron beam at the Brookhaven medical research reactor (BMRR) taking about an order of magnitude longer than comparable Monte Carlo calculations.

Estimating radiation doses from multidetector CT using Monte Carlo simulations: effects of different size voxelized patient models on magnitudes of organ and effective dose.

This work demonstrates the ability to estimate both individual organ and effective doses from any arbitrary CT scan protocol on individual patient-based models and to provide estimates of the effect of patient size on these dose metrics.

Adaptation of GEANT4 to Monte Carlo dose calculations based on CT data.

The emphasis is focused on modifications of the GEANT4 source code to meet the requirements for fast dose calculations, which include a quick voxel search algorithm, fast volume optimization, and the dynamic assignment of material density.