Cálculo dosimétrico de haces de conos de radiocirugía con método Monte Carlo / Dosimetric calculation of radiosurgery cone beams with Monte Carlo method

Sandrini, Bruno (2021) Cálculo dosimétrico de haces de conos de radiocirugía con método Monte Carlo / Dosimetric calculation of radiosurgery cone beams with Monte Carlo method. Proyecto Integrador Ingeniería Nuclear, Universidad Nacional de Cuyo, Instituto Balseiro.

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Resumen en español

Los campos pequeños de radiocirugía fomentan la utilización de sistemas de cálculos reduntantes e independientes para complementar las mediciones experimentales. Actualmente, el código EGSnrc para simulaciones Monte Carlo resulta el gold standard internacional en radioterapia. En el presente trabajó se utilizaron los códigos BEAMnrc y DOSXYZnrc, derivados de EGSnrc, para modelar en su totalidad el acelerador Elekta Synergy Platform de INTECNUS, junto con los conos de radiocirugía que posee la institución. Utilizando mediciones experimentales de referencia, realizadas con cámaras tipo pin point CC01 y el diodo estereotactico Razor DD de Iba Dosimetry, se derivó una energía efectiva del haz de electrones del acelerador de 6.5 MeV, para la cual se encontró un solapamiento satisfactorio entre las mediciones de referencia y las simulaciones, tanto para campos abiertos como para todos los conos bajo estudio. Se confeccionó también un sistema de cálculo de dosis independiente basado en el modelo del acelerador realizado. El mismo se basa en un conjunto de códigos que permiten generar los inputs necesarios para simular tratamientos clínicos a partir de información contenida en archivos DICOM. El tratamiento contempla la generación de fantomas antropomorcos en DOSXYnrc, y el movimiento sincronizado del colimador secundario, el MLC y el acelerador alrededor del fantoma/paciente. Se obtiene luego de simular la distribución de dosis normalizada sobre el fantoma generado.

Resumen en inglés

The use of small fields in stereotactic radiosurgery encourage the use of independent and redundant computational systems to complement experimental measurements. Currently, the EGSnrc code for Monte Carlo simulations is the international gold standard in radiotherapy. In the present work, the codes BEAMnrc and DOSXYZnrc, derived from EGSnrc, were used to fully model the Elekta Synergy Platform accelerator from INTECNUS, together with the radiosurgery cones owned by the institution. Using experimental reference measurements, carried out with CC01 pin point microchambers and RAZOR diode detectors from Iba Dosimetry, an effective electron incident energy of 6.5 MeV was found to produce a satisfactory overlap of simulations and measured elds, both for open fields and elds collimated with stereotactic cones. An independent dose calculation system based on the accelerator model was also developed. Said tool is based on a set of codes that allow generating the required inputs to simulate clinical treatments from information contained in DICOM les. The treatment contemplates the generation of anthropomorphic phantoms in DOSXYnrc, and the synchronized movement of the secondary collimator, the MLC and the accelerator around the phantom/patient. After simulating, the normalized dose distribution in the phantom is obtained.

Tipo de objeto:Tesis (Proyecto Integrador Ingeniería Nuclear)
Palabras Clave:Radiotherapy; Radioterapia; Radiosurgery; Radiocirugía; Cones; Conos; Dosimetry; Dosimetría; Monte Carlo method; Método de Monte Carlo
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Materias:Medicina > Radioterapia
Divisiones:Centro Integral de Medicina Nuclear y Radioterapia. Fundación INTECNUS
Código ID:1031
Depositado Por:Tamara Cárcamo
Depositado En:29 Abr 2022 09:48
Última Modificación:29 Abr 2022 09:48

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