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- Scatter radiation exposure during mobile X-Ray examinationsPublication . Abrantes, António; Rebelo, Carina; Sousa, Patrick; Rodrigues, Sónia; Almeida, Rui; Pinheiro, João; Azevedo, Kevin; Ribeiro, Luís PedroThe main goal of this research was to quantify scatter radiation exposure from mobile x-ray examinations. The simulation consisted of reproducing the technical conditions for the chest anteroposterior (AP) examination in supine and semi-supine positions as well as for the abdomen tangential projection, using a full body anthropomorphic phantom and an x-ray detector. For distances above 1m, the national dose limits for exposed workers is not exceeded (12 mSv/year), but for members of the public it is exceeded (2 mSv/year). Therefore, exposed workers should use a personal dosimeter, employ protective measures and stand behind the mobile equipment. The use of ionising radiation for diagnostic and treatment purposes has increased due to the development of new equipment and easier access to radiologic examinations.
- Effect of maternal restricted diet during late gestation on muscle and bone development in sheep offspringPublication . Estêvão, Dulce; Harrison, Adrian; McKenzie, S. H.; Ribeiro, Luís Pedro; Tygesen, M. P.; Sancho, Teresa; Power, DeborahChanges in intrauterine environment, including nutrient availability, have been associated with fetal programming, contributing to different phenotypes which may determine health and susceptibility to disease throughout life. These changes seem to be mediated through alterations in both anabolic and catabolic hormone levels of maternal, placental and/or fetal origin. The present work aimed to evaluate how maternal under-nutrition during late pregnancy affects muscle and bone growth. Pregnant ewes were divided into two groups, one fed ad libitum and the other fed a restricted diet (50% of total energy requirements) during the last 6 weeks of gestation. Three twin carrying ewes from each feeding group were euthanized 6 days pre parturition. The remaining ewes gave birth normally and reared their lambs. At approximately day 30 post partum, 5 lambs from each of the feeding groups were euthanized and samples collected. Nutrient restriction during late gestation did not affect intrauterine axial growth, although weight at birth and the muscle weight were significantly lower than the ad libitum fed lamb fetuses. Bone development is less affected cf muscle development during periods of maternal feed restriction; however, catch-up growth of muscle occurs when lambs (30 days post-parturition) have access to adequate rations. In utero irrespective of maternal nutrient supply dry muscle mass is correlated (r=0.94) to bone development (bone weight, femur length and femur mineral density). In contrast, post partum growth of and skeleton are less tightly coupled and unaffected by the events in utero. A detailed examination of how maternal nutrient supply affects endocrine parameters in utero will be required to assess if it affects susceptibility post-partum to endocrine dysfunction.
- Image quality control in digital radiologyPublication . Cândido, Susana; Ribeiro, Luís Pedro; Ribeiro, Anabela; Abrantes, António; Pinheiro, João; Almeida, Rui; Azevedo, KevinImage Quality Control is an important factor that contributes to the improvement of patient care and overall diagnostic accuracy. Our purpose was to elaborate Quality Control Charts and demonstrate the importance of image quality control in a radiology department. A total of 37 random samples, composed of 30 x-ray exams each, were selected and analyzed. Primarily, data about image non-conformities were compiled to make three distinct Quality Control Charts. Secondly, improvement and corrective actions were suggested. Our results allowed us to identify and account for different types of non-conformities found on x-ray images. This illustrates the importance and necessity for the implementation of an adequate Image Quality Control in Digital Radiology.
- Screening of breast lesions: a comparative study between mammography, B-mode ultrasonography, sonoelastography and histological resultsPublication . Pardal, Raquel Constantino; Abrantes, António; Ribeiro, Luís Pedro; Almeida, Rui; Azevedo, Kevin; Figueiredo, Teresa Leonor; Rodrigues, SóniaTo compare the capacity of mammography, sonoelastography, B-mode ultrasonography and histological analysis to differentiate benign from malignant breast lesions. Materials and Methods: A total of 12 histopathologically confirmed breast lesions were documented. The lesions were assessed by means of mammography, B-mode ultrasonography and sonoelastography, and histopathological analysis was utilized as a gold standard. Sensitivity and specificity were calculated. A receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic performance of the mentioned techniques. Results: Sensitivity and specificity in the differentiation between benign and malignant lesions were respectively 100% and 50% for mammography, 100% and 71% for B-mode ultrasonography, and 67% and 83% for sonoelastography. The area under the ROC curve was calculated for the three imaging modalities and corresponded to 0.792 for mammography, 0.847 for B-mode ultrasonography, and 0.806 for sonoelastography. Conclusion: Sonoelastography demonstrated higher specificity and lower sensitivity as compared with mammography and B-mode ultrasonography. On the other hand, B-mode ultrasonography had the largest area under the ROC curve. Sonoelastography has demonstrated to be a promising technique to detect and evaluate breast lesions, and could potentially reduce the number of unnecessary biopsies.
- Practice of martial arts and bone mineral density in adolescents of both sexesPublication . Ito, Igor Hideki; Mantovani, Alessandra Madia; Agostinete, Ricardo Ribeiro; Costa Junior, Paulo; Zanuto, Edner Fernando; Christofaro, Diego Giulliano Destro; Ribeiro, Luís Pedro; Fernandes, Rômulo AraújoThe purpose of this study was to analyze the relationship between martial arts practice (judo, karate and kung-fu) and bone mineral density in adolescents.METHODS: The study was composed of 138 (48 martial arts practitioners and 90 non-practitioners) adolescents of both sexes, with an average age of 12.6 years. Bone mineral density was measured using Dual-Energy X-ray Absorptiometry in arms, legs, spine, trunk, pelvis and total. Weekly training load and previous time of engagement in the sport modality were reported by the coach. Partial correlation tested the association between weekly training load and bone mineral density, controlled by sex, chronological age, previous practice and somatic maturation. Analysis of covariance was used to compare bone mineral density values according to control and martial arts groups, controlled by sex, chronological age, previous practice and somatic maturation. Significant relationships between bone mineral density and muscle mass were inserted into a multivariate model and the slopes of the models were compared using the Student t test (control versus martial art).RESULTS: Adolescents engaged in judo practice presented higher values of bone mineral density than the control individuals (p-value=0.042; Medium Effect size [Eta-squared=0.063]), while the relationship between quantity of weekly training and bone mineral density was significant among adolescents engaged in judo (arms [r=0.308] and legs [r=0.223]) and kung-fu (arms [r=0.248] and spine [r=0.228]).CONCLUSIONS: Different modalities of martial arts are related to higher bone mineral density in different body regions among adolescents.
- Formação e desenvolvimento profissional dos técnicos de diagnóstico e terapêutica em PortugalPublication . da Silva, Carlos; Abrantes, António; Soares, Paula; Silva, Tânia; Almeida, Rui; Ribeiro, Luís PedroNa atualidade, o ensino e a formação assumem uma significativa centralidade nas estratégias de desenvolvimento dos países europeus. No caso concreto da área da Saúde em Portugal, a necessidade de melhorar e otimizar as características da prestação de cuidados de saúde e a própria evolução do trabalho nos hospitais e centros de saúde têm apelado a uma renovação de conteúdos e das modalidades de educação e formação inicial e continua dos diferentes grupos profissionais (médicos, enfermeiros, dos técnicos superiores de diagnóstico e terapêutica, outros técnicos superiores da área da saúde). Isso supõe, por exemplo, que a educação e formação dos técnicos superiores de diagnóstico e terapêutica (TSDT) promova, entre outros aspetos, a adequação das qualificações profissionais às constantes mudanças dos estados de saúde e de doença dos cidadãos, para além de realizar a sua função fundamental de contribuir para o desenvolvimento e satisfação pessoal, bem como para fomentar o exercício da cidadania e as competências e habilidades nucleares em avaliação das tecnologias da saúde das diferentes categorias profissionais da saúde.
- 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.
- A violência nas organizações dos Serviços de Saúde: Dilemas da vivência dos Técnicos de Radiologia em Portugal. In Caballero, E. (Dir.). Sociedades y Fronteras: Actas del IX Congresso Andaluz de SociologíaPublication . Abrantes, António; da Silva, Carlos; Sequeira, Bernardete; Ribeiro, Luís Pedro; Azevedo, Kevin; Almeida, RuiA problemática da violência está na ordem do dia. Rost & Kathleen constataram que a violência sobre os profissionais de saúde nas sociedades ditas desenvolvidas está a atingir limites preocupantes, constituindo na atualidade um grave problema de saúde pública.
- 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.
- Estudo da dose nos exames de tomografia computadorizada abdominal em um equipamento de 6 cortesPublication . Rodrigues, Sónia; Abrantes, António; Ribeiro, Luís Pedro; Almeida, RuiObjective: To determine the effective dose in abdominal computed tomography imaging and to study the influence of patients’ characteristics on the received dose. Materials and Methods: Dose values measurements were performed with an ionization chamber on phantoms to check the agreement between dose values and those presented by the computed tomography apparatus, besides their compliance with the recommended reference dose levels. Later, values of dose received by physically able patients submitted to abdominal computed tomography (n = 100) were measured and correlated with their anthropometric characteristics. Finally, the dose to organs was simulated with the Monte Carlo method using the CT-Expo V 1.5 software, and the effect of automatic exposure control on such examinations. Results: The main characteristics directly influencing the dose include the patients’ body mass, abdominal perimeter and body mass index, whose correlation is linear and positive. Conclusion: The radiation dose received from abdominal CT scans depends on some patient’s characteristics, and it is important to adjust the acquisition parameters to their dimensions.