Browsing by Author "Lesyuk, Oksana"
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- Anode heel effect attenuation in lumbar spine radiography: can the use of aluminium filters improve clinical practice of radiographers?Publication . Ribeiro, Luís Pedro; Abrantes, António; Lesyuk, Oksana; Dores, Rúben; Sousa, Patrick; Rodrigues, Sónia; Almeida, Rui; Azevedo, Kevin; Soares, Joana; Aleixo, JoãoPurpose: The aim of this study was to design an aluminiumbased fi lter to reduce the anode heel eff ect in lumbar spine radiographs. Methods: Initially, lumbar spine examinations were observed in a public imaging department to determine standard exposure parameters. Then, the characterization of the anode heel eff ect was made using the Unfors Xi R/F detector and, based on the data collected, aluminium fi lters were designed with a wedge shape and thicknesses ranging from 0.1 to 4.0 mm. The assessment of the entrance skin dose (ESD) reduction was performed on the anthropomorphic phantom with and without fi lters, using the universal dosimeter UNIDOS E equipped with an ionization chamber. Finally, the image quality assessment was performed with the Pehamed Phantom Digrad A+K and image quality surveys were applied to radiographers and radiologists. Results and Discussion: Uniformity of the beam was achieved, especially with fi lter number 2, which presents a signifi cant variation of 9% between the cathodic and anodic side. This fi lter contributes to ESD reduction of 35% and 36% for AP and lateral projection, respectively. Also, according to radiographers and radiologists, it improves the image quality of lumbar spine radiography. Conclusion: The use of aluminium fi lters can be advantageous in the clinical practice of radiographers when performing lumbar spine radiographs since it allows the standardization of the anode heel eff ect, reduces the radiation dose to the patient and does not compromise image quality.
- Avaliação da exposição à Radiação Ionizante de pacientes submetidos a procedimentos de CPRE com recurso a fluoroscopiaPublication . Granadas, Marisa; Ribeiro, Luís; Abrantes, António; Sousa, P.; Almeida, Rui; Rodrigues, S.; Lesyuk, OksanaObjetivo: Avaliar as doses de exposição a radiação ionizante de pacientes submetidos a procedimentos de CPRE. Metodologia: Recolha de uma amostra de dados em duas instituições num total de 267 pacientes, 198 numa instituição pública (A) e 69 numa instituição privada (B). Resultados: A mediana dos tempos de fluoroscopia é semelhante entre as duas instituições em estudo, 4 minutos e 17 segundos na instituição A e 4 minutos e 21 segundos na instituição B, porém verifica-se uma diferença na mediana do DAP com valores de 3,60 Gy.cm2 e 13,21 Gy.cm2. A dose efetiva mediana estimada foi, respetivamente, de 0,94 mSv e 3,43 mSv. Conclusão: As doses de exposição encontram-se dentro do intervalo de valores praticados na literatura, sendo a avaliação do risco de desenvolvimento de cancro, como consequência da exposição a procedimentos de CPRE, na Instituição A de 0,006% e na Instituição B de 0,025%.
- Effectiveness of shielding in computed tomography examinationsPublication . Coelho, Soraia; Azevedo, Kevin; Abrantes, António; Rodrigues, Sónia; Ribeiro, Luís; Vicente, Bianca; Almeida, Rui; Lesyuk, OksanaComputed Tomography (CT) is an important tool in providing high-quality crosssectional images of the body using ionizing radiation and computational reconstruction techniques. CT has transformed much of medical imaging by providing three-dimensional views of the organ or body region of interest. CT involves larger radiation doses than the more common, conventional x-ray imaging procedures, and technological developments have contributed to the increase of number and diversity of scanning procedures, in adults and pediatrics patients. Since an increasing number of CT scans are being obtained, the...
- Evaluation of the patient exposure dose during ERCP Fluoroscopy guided proceduresPublication . Granadas, Marisa; Rodrigues, Sónia; Sousa, Patrick; Lesyuk, Oksana; Vicente, Bianca; Almeida, Rui; Azevedo, Kevin; Ribeiro, Luís; Abrantes, AntónioEndoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic/therapeutic fluoroscopy guided procedure that includes upper gastrointestinal endoscopy allowing the treatment of the bile and pancreatic ducts pathologies. Currently, ERCP is mostly used in therapy, which turns in to longer procedures, with potential higher doses of ionizing radiation to the patient and due to the cancer development risk it's relevant to evaluate dose exposure during ERCP. The International Atomic Energy Agency (IAEA) defined the mean dose area product (DAP) for ERCP diagnostic procedures as 15 Gy.cm2 and mean...
- Patient safety culture: radiographers’ perceptionPublication . Ribeiro, Luís Pedro; Ribeiro, A.M.; Azevedo, Kevin; Abrantes, António; Lesyuk, Oksana; Almeida, Rui; Fernandes, Sara; da Silva, Carlos; Rodrigues, SóniaResearch to evaluate radiographers’ perceptions about patient safety culture in Portuguese public and private imaging facilities found that overall perception is positive but the safety culture dimensions rating should guide culture development of safety culture improvement action plans.
- Quality of life and professional quality of life of radiographers working in Portugal and England - A comparative studyPublication . Pinto, Inês; Ribeiro, Luís; Rodrigues, Sónia; Vicente, Bianca; Abrantes, António; Almeida, Rui; Lesyuk, OksanaGlobal healthcare systems are characterized by a very competitive era, marked by constant changes, recurrent technological innovations, increased workflows, and many other aspects that require qualified and motivated healthcare professionals to be able to meet the demands and to provide quality healthcare services 1, 2, 3. Although it is a concept susceptible to many definitions due to its multidimensality and subjectivity, the World Health Organization (WHO) defines Quality of Life (QL) as an individual’s perception of their position in life concerning the values and culture...
- Study of scattered radiation during fluoroscopy in hip surgeryPublication . Lesyuk, Oksana; Sousa, Patrick; Rodrigues, Sónia Isabel do Espírito Santo; Abrantes, António; Almeida, Rui; Pinheiro, João; Azevedo, Kevin; Ribeiro, LuísObjetivo: Medir a intensidade da dose de radiação espalhada em diferentes posições simulando uma intervenção cirúrgica no quadril. Materiais e Métodos: Simulou-se uma intervenção cirúrgica no quadril com apoio da fluoroscopia para estudar a distribuição da radiação espalhada no bloco operatório. Para simular o paciente foi utilizado um simulador antropomórfico de corpo inteiro e para medir a radiação utilizou-se um detector específico para medir raios X. Realizaram-se incidências com um equipamento de raios X tipo arco em C móvel, em modo de escopia contínua, com a ampola a 0° (configuração 1) e a 90° (configuração 2). Os parâmetros operacionais utilizados (voltagem, corrente, tempo de exposição) foram determinados por meio de um estudo estatístico resultante da observação de cirurgias ortopédicas de quadril. Resultados: Em todas as medições observaram-se exposições mais elevadas na configuração 2. Nas medições em função da altura, observaram-se os valores máximos da taxa de dose de 1,167 (± 0,023) µSv/s e 2,278 (± 0,023) µSv/s nas configurações 1 e 2, respectivamente, correspondendo à altura do tórax dos profissionais. No estudo em torno do paciente os valores máximos registraramse na posição ocupada pelo médico cirurgião. Conclusão: Concluiu-se que a exposição à radiação dos profissionais é baixa, podendo ainda ser reduzida mediante o uso de equipamentos de proteção individual
- Study of scattered radiation during fluoroscopy in hip surgeryPublication . Lesyuk, Oksana; Sousa, Patrick Emmanuel; Rodrigues, Sónia; Abrantes, António; Almeida, Rui; Pinheiro, João; Azevedo, Kevin; Ribeiro, Luís PedroObjective: To measure the scattered radiation dose at different positions simulating hip surgery. Materials and Methods: We simulated fluoroscopy-assisted hip surgery in order to study the distribution of scattered radiation in the operating room. To simulate the patient, we used a anthropomorphic whole-body phantom, and we used an X-ray-specific detector to quantify the radiation. Radiographs were obtained with a mobile C-arm X-ray system in continuous scan mode, with the tube at 0° (configuration 1) or 90° (configuration 2). The operating parameters employed (voltage, current, and exposure time) were determined by a statistical analysis based on the observation of orthopedic surgical procedures involving the hip. Results: For all measurements, higher exposures were observed in configuration 2. In the measurements obtained as a function of height, the maximum dose rates observed were 1.167 (± 0.023) µSv/s and 2.278 (± 0.023) µSv/s in configurations 1 and 2, respectively, corresponding to the chest level of health care professionals within the operating room. Proximal to the patient, the maximum values were recorded in the position occupied by the surgeon. Conclusion: We can conclude that, in the scenario under study, health care professionals workers are exposed to low levels of radiation, and that those levels can be reduced through the use of personal protective equipment.