Browsing by Issue Date, starting with "2017-09"
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- Binocular function years after surgeryPublication . Reich-d'Almeida, F.; Lança, Carla; Reich-d'Almeida, IsabelPurpose - To demonstrate that in surgically treated infantile esotropia patients, with no previous signs of binocularity, it is possible after a very long therapy with medical and orthoptic regular follow up, to achieve functional rehabilitation well above the conventionally accepted age for sensorial recovery.
- Compreender o usuário: o papel da cognição, da emoção e das atitudesPublication . Antunes, Ana CristinaPorque é que os usuários preferem determinados sistemas e medias digitais e rejeitam outros? Porque é que usam somente algumas funcionalidades e não todas as disponibilizadas pelo sistema? Porque é que cometem erros e o que fazem perante estes erros? Este capítulo pretende dar resposta a estas e outras questões relativas aos usuários, a partir da análise do seu funcionamento cognitivo, afetivo e atitudinal.
- CR radiation dose optimization strategies: clinical practice approachPublication . Borlinhas, Filipa; Afonso, José; Vicente, Ana Cristina; Venâncio, JoséIn medical radiation exposures, namely in Computed Tomography (CT), there is an inverse relationship between the image noise and radiation dose. Radiographers need to recognize the situations that require optimization and to apply optimization strategies, without compromise patient diagnosis. The purpose of this work, based on a literature review and on the analysis of routine CT procedures, is to provide an overview of CT optimization techniques feasible to implement in routine practice. The key parameters and the main situations that affect image quality and patient dose will be discussed. Several CT parameters can be adjusted such as potential and tube current, rotation time, Automatic Exposure Control (AEC), detectors configuration, slice thickness, Pitch, table speed, post-processing with the filter kernels, and so on. These parameters vary with patient anatomical region of interest, examination length, positioning, clinical information, and acquisition phases. Furthermore, there are new reconstruction algorithms developed by manufacturers that also help to optimize dose by reducing artifacts and image noise, and many studies state their superior results. Also, the knowledge on the CT parameters trade-offs between radiation dose and image quality is essential for dose optimization, so this will also be highlighted and described in this work. The solution for the excess of radiation dose problem is not only to reduce radiation dose in general but also to adequate and personalize this optimization to each patient and clinical situation. The literature points out some solutions to handle this problem and is very important that the Radiographers are familiar with those when performing CT examinations in practice.
- Literacia da informação em contexto universitário: uma intervenção necessáriaPublication . Lopes, Carlos; Sanches, Tatiana; Antunes, Maria Da Luz; Andrade, Isabel; Alonso-Arévalo, JulioUm conjunto de autores, de vários quadrantes, reuniu-se num Grupo de Investigação em Psicopatologia, Emoções, Cognição e Documentação, na linha de investigação – Literacia de Informação em Contexto Universitário, sediado no ISPA-Instituto Universitário – para procurar responder a uma lacuna que existia em Portugal: a falta de um livro em língua portuguesa para responder aos profissionais que exercem a sua ação em torno deste tema. A partir de contributos nacionais e internacionais, com o que de mais atual se faz nesta área, procurou-se ancorar a literacia da informação em investigação teórica para sustentar as práticas, mas igualmente apresentar casos exemplares para inspiração e replicação em diferentes contextos educativos. Os contributos que formam o ebook, recentemente publicado, pretenderam trazer ideias e partilhar experiências, alargar horizontes e criar alguma luz sobre o panorama nacional relativamente à literacia da informação. As diferentes formulações, perspetivas e abordagens procuraram providenciar um aporte diversificado e abrangente à temática e responder ao desafio lançado por profissionais ligados à área, particularmente os intervenientes nas bibliotecas de ensino superior. Este webinar pretende descrever o desafio que mobilizou a concretização deste livro, explicando e incentivando à melhor aprendizagem e ao sucesso académico, através da consciência de uma ação concreta dos profissionais que, em contexto educativo no ensino superior, desenvolvem a sua ação com e pela literacia da informação.
- A fuzzy logic model to evaluate the lean level of an organizationPublication . Abreu, António; Calado, João Manuel FerreiraThis paper is concerned with the development of a holistic fuzzy logic model to evaluate the lean thinking environment in an organization. The development of such a model was based on a qualitative assessment approach, including quantitative basis, whose development has been based on fuzzy logic reasoning. Recourse to the use of fuzzy logic is justified by its ability to cope with uncertainty and imprecision on the input data, as well as, could be applied to the analysis of qualitative variables of a system, turning them into quantitative values. The proposed approach was structured with the aim of to achieve a model able to cope with the specificities ofany kind of organization regardless of their nature, size, strategy and market positioning. Furthermore, the proposed methodology allows the systematically identification of constraint factors existing in an organization and, thus, provide the necessary information to the manager to develop a holistic plan for continuous improvement. To evaluate the robustness of the proposed approach, the methodology was applied to a maintenance and manufacturing aeronautical organization.
- Is the air we breathe while sleeping conditioning our sleep quality?Publication . Canha, Nuno; Lage, J.; Belo, Joana; Viegas, Carla; Faria, Tiago; Cabo Verde, Sandra; Cruz, M. Meira; Alves, C.; Almeida, Susana MartaHuman exposure to air pollution: high variability of air pollutants concentration within a city; people spend more than 90% of their time in indoor environments; high variability of patterns of spaces’ occupation within the population. What do we know now? Sleep has a vital role in human welfare; low ventilation rates; breathing area closer to potential sources of pollutants; lack of studies about exposure during sleep. Why sleep matters – the economic costs of insufficient sleep: sleep has an overall impact on the countries’ richness; lower productivity levels and higher mortality risks related to insufficient sleep can result in substantial economic losses to modern economies; insufficient sleep among its populations cost the 5 OECD countries under consideration (USA, UK, Japan, Germany and Canada) up to $680 billion of economic output lost every year. The aim of this study: Do indoor air quality influences sleep quality?
- Information literacy in Portuguese university context: a necessary interventionPublication . Lopes, Carlos; Sanches, Tatiana; Antunes, Maria Da Luz; Andrade, Isabel; Alonso-Arévalo, JulioDue to the Bologna process, but also in light of technological and communication changes, the current context of higher education requires a reconfiguration of the way we learn. Driven to deal with new learning environments, students must handle information, know how to choose it, interpret it, evaluate it, and use it. It is, therefore, necessary to value information (in itself and for what it represents in terms of rights and the exercise of citizenship) and understand that its domain, that is, its literacy, is an essential investment in the context of higher education. A group of authors from various quarters came together in a research group – Grupo de Investigação em Psicopatologia, Emoções, Cognição e Documentação, Information Literacy in the University Context, based in ISPA, Instituto Universitário – in an attempt to respond to a gap that exists in Portugal: the lack of a book in Portuguese to meet the needs of professionals working on this theme. Based on national and international contributions, with the newest developments in this field, this open access e-book seeks to anchor information literacy in theoretical research to sustainable practices, but also to present exemplary cases for inspiration and replication in different educational contexts. It presents ideas and shares experiences, broadens horizons and sheds some light on the national panorama as regards information literacy, barely visible before this initiative. Different formulations, perspectives, and approaches seek to provide diverse, extensive input and to respond to the challenge laid down by professionals of this area (especially those intervening in higher education libraries) who have interacted with the authors over the past few years. The purpose of this paper is to describe the challenge which motivated this research work, explaining and encouraging improved learning and academic achievement, through awareness of concrete action by the professionals who develop their action with and for information literacy, in the higher education context.
- Dose and image quality in computed tomography: an overview of Portuguese dataPublication . Coutinho, Ana Margarida; Teixeira, Nuno; Trindade, Hugo; Coutinho, GuilhermeComputed Tomography exams expose patients to higher dose levels than most exams in radiology and the number of CT exams is increasing year after year in Portugal. In 2009 were performed 1.1 million CT exams and later in 2014, there were 1.6 million. This study aims to analyze dose and image quality data gathered from 180 distinct computed tomography systems, which represents 350 quality assurance interventions done in Portuguese national health units (mainland and islands) between 2014 and 2017. In the quality assurance interventions, a Catphan® 500 phantom was aligned in the center of the gantry and irradiated, for analysis of six parameters: CT numbers, slice thickness, low and high contrast resolution, uniformity and noise. Afterwards, an ionization chamber (Raysafe Xi CT sensor) was placed in the interior of a PMMA (polymethylmethacrylate) phantom and the Computed Tomography Dose Index (CTDI) was measured. Data analysis was performed using IBM SPSS v.22.0. In order to verify the CT numbers, four materials with different densities were analyzed and the mean CT numbers obtained were: -980 HU (Air), -943 HU (Teflon), -115 HU (Acrylic) and -99 HU (LDPE). The high contrast resolution values were determined for X-ray energies in a range of 80 kV to 100 kV at 200 mA and the mean spatial resolution obtained was 8 lp/cm with a gap size of 0,063 cm. When increasing the voltage to 130-140 kV the mean spatial resolution was 9 lp/cm with a gap size of 0,056 cm. Dose measured in the head and body scan techniques, with a voltage between 80 kV and 100 kV at 100 mA and 10 mm slice thickness was 6 my and 3 mGy, respectively. When increasing the voltage to 130-140 kV the mean values obtained were 23 mGy (head) and 12 mGy (body). These results show that with lower voltage the CTDI is four times lower while keeping an adequate spatial resolution. Adequate CT protocols are very important to ensure safety to all patients, and specifically designed pediatric protocols should be used, once children are more sensitive to the effects of ionizing radiation. It is important to adopt CT exams in order to minimize exposure while providing good diagnostic quality. In this study a comparison between adults and children protocols is made (using international publications like the ones form AAPM - American Association of Physicists in Medicine), using dose and resolution data from the Portuguese equipment.
- Peters’ anomaly – Strabismus and amblyopia: a case reportPublication . Poças, Ilda Maria; Lino, Pedro Miguel; Abrantes, InêsPeter’s Anomaly, first described by Albert Peter in 1906, consists of a central corneal opacity related to a malformation of the anterior segment of the eye. It’s a disease in a constellation of diseases that causes corneal opacity, iridocorneal adhesions due to dysgenesis of the anterior segment during development. Peters’ Anomaly can cause devastating corneal opacity in an infant leading to severe amblyopia. It frequently occurs with associated strabismus, usually convergent (sensorial type), having also dissociated vertical deviation (DVD). The exact prevalence of Peters’ Anomaly is unknown. This condition is one of a group of disorders known as congenital corneal opacities, which affect three to six individuals per 100,000. Physiopathology: Peter’s Anomaly is a rare dramatic finding at birth, manifests in utero during the first trimester of pregnancy (10-16 weeks of gestation), and can be associated with other systemic malformations. It is classified in two types, which are distinguished by their signs and symptoms. Peters’ Anomaly Type I is characterized by an incomplete separation of the cornea and iris and mild to moderate corneal opacity. Type II is characterized by an incomplete separation of the cornea and lens and severe corneal opacity that may involve the entire cornea. Type II is more associated with systemic alterations and tends to be bilateral. During development of the eyes, the elements of the anterior segment form separate structures. However, in Peters’ Anomaly, development of the anterior segment is abnormal, leading to incomplete separation of the cornea from the iris or the lens. As a result, the cornea is cloudy (opaque), which causes blurred vision. The opaque area (opacity) of the cornea varies in size and intensity from a small, faint streak to a large, white cloudy area that covers the front surface of the eye. Additionally, the location of the opacity varies, the cloudiness may be at the center of the cornea or off-center. Large, centrally located opacities tend to cause poorer vision than smaller, off-center ones. It is important a binocular vision evaluation in order to identify, qualify and quantify the type of ocular deviation, characterize the real and potential binocular single vision and the amblyopia. The motor and sensorial tests must be appropriate to the case in question, in particular, visual acuity and fixation. The treatment involves a corneal transplant which is often complicated due to the young age of the affected. To prevent amblyopia and provide visual rehabilitation a penetrating keratoplasty (PKP) was recommended. Many children with PKP for Peters’ Anomaly Type I can experience good or functional vision in their operated eye. After keratoplasty is very important to improve visual acuity and do amblyopia treatment. Children with glaucoma have a poorer visual prognosis. The treatment of strabismus in cases of Peters’ Anomaly follows the general rules of treatment of concomitant strabismus. The first step should be the best optical correction possible. The surgical proposal must be made after achieving visual acuities between the two eyes. In congenital strabismus, late surgery will only have aesthetic value.
- Risks of fetal exposure to ionizing radiationPublication . Patrício, Cristina; Chagas, Rita; Gonçalves, SaraIntroduction - Imaging diagnostic exams are often used during pregnancy. The most commonly used methods are those that do not pose a risk to the fetus, such as Ultrasound and Magnetic Resonance. Exams that involve the use of ionizing radiation are usually postponed or dismissed due to potential health risks to the fetus. However, a delayed diagnosis due to non-use of these exams may be more harmful to maternal and fetal health than the possible risks associated with the use of radiation. Methods - In this work, we propose to review the conclusions of the following articles: 1. Garcia TJ, Lara PHS, Kinjo CS, Bezerra EA, Higasiaraguti M, Oliveira NM, Sousa NC, Yonamine RY, Sales SMA, Morimoto TP, Zamboni JW, Sancovski M. Aspectos atuais em imagenologia na gestação. Arquivos Brasileiros de Ciências da Saúde. 2012 Dec; 47(3):143-148; 2. D’lppolito G, Medeiros RB. Exames Radiológicos na Gestação. Radiologia Brasileira. 2005 Nov/Dec; 38(6):447-450; 3. Baptista E, Domingues AP, Duarte H, Vasco E, Moura P. Segurança dos exames imagiológicos na gravidez. Acta Obstétrica e Ginecológica Portuguesa. 2014; 8(2):176-185; 4. Videira AI, Nogueira A. Exposição às Radiações Ionizantes na Gravidez: Efeitos Biológicos no Embrião e no Feto. Arquivos da Maternidade Dr. Alfredo da Costa. 2002 Dec;8(2):66-71. We have analyzed them and compiled in a single document the conclusions reached by these authors. It’s important to emphasize that none of the conclusions presented are of our authorship, we only refer the ideas of other authors. Keywords: “fetal exposure”; “dose limits”; “pregnancy”; “nuclear medicine”; “radiological examinations” Results - Exposure to fetal doses below 100 mGy is not associated with increased deterministic effects, so this dose is not considered indicative of pregnancy discontinuation. However, this hypothesis should be considered when the radiation dose is greater than 250 mGy (there is no exam that exposes the fetus to this level of radiation but may occur in a combination of tests). Conclusions - It’s of utmost importance, before prescribing a radiological examination to a pregnant woman, to be sure that it’s indispensable, that it cannot be postponed or if there is no other safer exam for the fetus that gives us the same information necessary for a correct diagnosis. If it cannot be avoided, before we submit a pregnant woman to ionizing radiation we must estimate the absorbed dose by the fetus, based on the protocol of the exam to be performed. Therefore, the fear that diagnostic exams that use ionizing radiation may be harmful to the fetus is, in most cases, unjustified, because the fetal dose received after most procedures is well below the threshold dose for the occurrence of deterministic effects.