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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.
- 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.
- Quality in computorized tomography: from image acquisition to dose, concepts, myths and definitionsPublication . Abrantes, António; Ribeiro, Luís; Almeida, Rui; Pinheiro, João; Azevedo, Kevin; da Silva, CarlosWith this review article, we intend to demonstrate the importance of Computerized Tomography (CT) in healthcare quality and safety. The concept of safety in CT is wider than for general healthcare. Safe healthcare provided using CT must include diagnostic image quality and reliability, as this is the only way to ensure diagnostic accuracy. The images must be acquired with the most adequate protocols available and with the lowest achievable radiation dose. In this article we will focus primarily on the concepts of dose, since this variable strongly affects the image quality and the consequent diagnostic accuracy. In methodological terms, 73 papers and 6 catalogues issued by the manufacturers of CT equipment, that included the keywords low dose, ultra-low dose and dose reduction were analysed. After review of these articles we found that about 82% are chest exams, namely the lungs. The remaining were subdivided mainly by studies of the sinuses, heart and bone segments. After this review we selected the only 10 articles that present the keywords and simultaneously quantify the dose reduction. Given the lack of precision associated with these terms, introduced mainly by commercial catalogues of different equipment brands, we intend to demonstrate that the concepts low dose and ultra-low dose are wrapped in unclear marketing strategies, without a strict and unambiguous definition of what is the effective dose. We propose that these concepts should be clearly defined and a precise indication of the effective dose reduction value should be compared to the default value (standard diagnostic dose) by exam region. Therefore, it is demonstrated that there is no concrete definition of what low dose or ultra-low dose are. These slogans cannot be used until they are not holistically defined, as well as the correspondent dose reduction value.
- 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.
- Bone density and fall risk screening in Algarve: A preliminary studyPublication . Ribeiro, Luís Pedro; Pinheiro, João; Abrantes, António; Ribeiro, A.M.; Vicente, Bianca I. C.; Almeida, Rui; Gonçalves, Tânia; Ferreira, M. A. G. A.; Farinha, Maria Conceição; Azevedo, KevinOsteoporosis is a major cause of morbidity and mortality around the world and is a silent disease characterized by low bone strength that results in an increased risk of fracture. The benefits of being physically active in advanced ages to reduce the loss of bone mineral density (BMD) and improve functional capacities are well known. Quantitative ultrasound (QUS) is a peripheral bone densitometry technique that is rapidly gaining in popularity for the assessment of skeletal status, along with fall risk assessment. This chapter consists of a brief review of the literature on osteoporosis and describes ongoing activities on bone density and fall risk prevention in Algarve, Portugal as part of EIP AHA´s action group on fall prevention with the presentation of a preliminary study. This study aimed to demonstrate that the postmenopausal female seniors who adhere to the recommendations for the regular program of physical activity after osteoporosis screening one year later show a slower decrease in BMD.
- Image quality assessment of head CT: Control charts as an useful instrumentPublication . Guiomar, Joana Reis; Ribeiro, Luís Pedro; Ribeiro, Anabela; Abrantes, António; Pinheiro, João; Almeida, Rui; Azevedo, KevinThemain objective of this research was to determine if the diagnostic image, acquired by CT scan, meets the quality criteria previously established for head CT exams. A total of 360 Head Computed Tomography exams were analyzed, using a checklist. For data collection, quality criteria were created, organized into four criteria groups, consisting of multiple items that must appear in the images studies. After data processing, a large number of non-conformexaminations were identified in than more than 50% of the sample. We concluded the main causes of these results are: the “incorrect or incomplete positioning”, the "lack of name of the radiographer and “motion artefacts”. Therefore it is essential to implement a checklist for a systematic evaluationof procedures.