Evaluation of occupational exposures in Endoscopic Retrograde Cholangiopancreatography using Monte Carlo simulation

• Ano de defesa: 2020
• Autor(a) principal: Souza, Lucas Wilian Gonçalves de
• Orientador(a): Neves, Lucio Pereira
• Banca de defesa: Milagre, Selma Terezinha , Caldas, Linda Viola Ehlin
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Uberlândia
• Programa de Pós-Graduação: Programa de Pós-graduação em Engenharia Biomédica
• País: Brasil
• Palavras-chave em Português: ERCP; Ionizing Radiation; Monte Carlo Simulation; Dosimetry; Radiation Protection; Radiação Ionizante; Simulação de Monte Carlo; Dosimetria; Proteção Radiológica
• Área do conhecimento CNPq: CNPQ::ENGENHARIAS::ENGENHARIA BIOMEDICA
• Link de acesso: https://repositorio.ufu.br/handle/123456789/29138; http://doi.org/10.14393/ufu.di.2020.295

The contemporary life style and the aging of world population have set a favorable scenario to the increase of hepatobiliary and pancreatic diseases. The Endoscopic Retrograde Cholangiopancreatography (ERCP) is one of the main medical techniques employed to diagnose and treat those diseases. ERCP is a fluoroscopy guided procedure, therefore it exposes patient and medical staff to ionizing radiation. This exposure may lead to tissue reactions and cancer later in life. The objective of this work was to apply Monte Carlo (MC) simulation to evaluate patient and staff radiation exposure during ERCP procedures. The simulated scenario reproduced a typical ERCP room equipped with an over-couch x-ray system. MASH3 and FASH3 virtual anthropomorphic phantoms were utilised to represent the patient, the physician and the assistant physician. The patient was placed in prone position on the table. The staff wore 0.5 mm Pb apron, thyroid collar and eyewear. The fluoroscopic parameters were tube voltage of 70, 80, 90, 100 and 110 kVp; the Field of View (FOV) sizes were 15×15 cm2, 17×17 cm2, 22×22 cm2, 25×25 cm2, 31×31 cm2 and 38×38 cm2. The x-ray spectra were simulated in SRS78 software and the Monte Carlo simulations were implemented in the Monte Carlo N-Particle eXtended (MCNPX) (version 2.7.0) code. For a given tube voltage, the results show an increase of patient conversion coefficients for effective dose CC[E] values for FOV sizes increments until the irradiated area suppressed patient area, then for larger FOV sizes, the CC[E] values decreased. For a defined FOV size, the patient CC[E] values raised as the tube voltage was increased. Concerning the staff, the CC[E] values increased for elevated tube voltages, given a fixed FOV size. Their CC[E] values also raised when the tube voltage was unchanged but the FOV sizes were expanded. The effective dose calculated from the mean CC[E] values and Dose Area Product (DAP) from the literature are in agreement with previous works. The estimated conversion coefficients for equivalent dose CC[HT] values are also consistent with the literature. This work presents the first results of a greater project focused on the radiation protection at an university hospital.