Haralick texture feature analysis for Monte Carlo dose distributions of permanent implant prostate brachytherapy.

Purpose: Demonstrate quantitative characterization of 3D patient-specific absorbed dose distributions using Haralick texture analysis, and interpret measures in terms of underlying physics and radiation dosimetry.

Methods: Retrospective analysis is performed for 137 patients who underwent permanent implant prostate brachytherapy using two simulation conditions: "TG186" (realistic tissues including 0-3.8% intraprostatic calcifications; interseed attenuation) and "TG43" (water-model; no interseed attenuation).

Haralick texture analysis for microdosimetry: characterization of Monte Carlo generated 3D specific energy distributions.

Explore the application of Haralick textural analysis to 3D distributions of specific energy (energy imparted per unit mass) scored in cell-scale targets considering varying mean specific energy (absorbed dose), target volume, and incident spectrum.Monte Carlo simulations are used to generate specific energy distributions in cell-scale water voxels ((1m)-(15m)) irradiated by photon sources (mean energies: 0.02-2 MeV) to varying mean specific energies (10-400 mGy).

Haralick texture feature analysis for characterization of specific energy and absorbed dose distributions across cellular to patient length scales.

To investigate an approach for quantitative characterization of the spatial distribution of dosimetric data by introducing Haralick texture feature analysis in this context.Monte Carlo simulations are used to generate 3D arrays of dosimetric data for 2 scenarios: (1) cell-scale microdosimetry: specific energy (energy imparted per unit mass) in cell-scale targets irradiated by photon spectra (I,Ir, 6 MV); (2) tumour-scale dosimetry: absorbed dose in voxels for idealized models ofI permanent implant prostate brachytherapy, considering 'TG186' (realistic tissues including 0% to 5% intraprostatic calcifications; interseed attenuation) and 'TG43' (water model, no interseed attenuation) conditions. Five prominent Haralick features (homogeneity, contrast, correlation, local homogeneity, entropy) are computed and trends are interpreted using fundamental radiation physics.

High spatial resolution dosimetry with uncertainty analysis using Raman micro-spectroscopy readout of radiochromic films.

Purpose: The purpose of this work is to develop a new approach for high spatial resolution dosimetry based on Raman micro-spectroscopy scanning of radiochromic film (RCF). The goal is to generate dose calibration curves over an extended dose range from 0 to 50 Gy and with improved sensitivity to low (<2 Gy) doses, in addition to evaluating the uncertainties in dose estimation associated with the calibration curves.

Methods: Samples of RCF (EBT3) were irradiated at a broad dose range of 0.

A study of Type B uncertainties associated with the photoelectric effect in low-energy Monte Carlo simulations.

To estimate Type B uncertainties in absorbed-dose calculations arising from the different implementations in current state-of-the-art Monte Carlo (MC) codes of low-energy photon cross-sections (<200 keV).MC simulations are carried out using three codes widely used in the low-energy domain: PENELOPE-2018, EGSnrc, and MCNP. Three dosimetry-relevant quantities are considered: mass energy-absorption coefficients for water, air, graphite, and their respective ratios; absorbed dose; and photon-fluence spectra.