272 resultados para Radiographic Image Interpretation, Computer-Assisted
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There are currently few studies exploring doctors' personal perspectives on integrating sexuality into medical consultations. This study focuses on the views of gynaecologists on introducing, or not introducing, sexuality into their work. A total of 30 semistructured interviews were conducted with gynaecologists in the French-speaking part of Switzerland. The thematic content analysis and computer-assisted lexical analysis (Alceste) on the interview transcripts highlighted four categories: perceptions and description of sexuality, patient's sexological history, training in sexology and perceived difficulties. It is observed that, above all, the 'medical dimension' characterises gynaecologists' perceptions. Of greater interest is our observation of disparities in gynaecologists' discussion of their practice, which is often the product of lay knowledge based on common sense and/or personal experience. Finally, the decision to integrate questions relating to sexuality seems to depend on non-medical factors such as the personal experience, interest or gender of the doctor.
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Intensity-modulated radiotherapy (IMRT) treatment plan verification by comparison with measured data requires having access to the linear accelerator and is time consuming. In this paper, we propose a method for monitor unit (MU) calculation and plan comparison for step and shoot IMRT based on the Monte Carlo code EGSnrc/BEAMnrc. The beamlets of an IMRT treatment plan are individually simulated using Monte Carlo and converted into absorbed dose to water per MU. The dose of the whole treatment can be expressed through a linear matrix equation of the MU and dose per MU of every beamlet. Due to the positivity of the absorbed dose and MU values, this equation is solved for the MU values using a non-negative least-squares fit optimization algorithm (NNLS). The Monte Carlo plan is formed by multiplying the Monte Carlo absorbed dose to water per MU with the Monte Carlo/NNLS MU. Several treatment plan localizations calculated with a commercial treatment planning system (TPS) are compared with the proposed method for validation. The Monte Carlo/NNLS MUs are close to the ones calculated by the TPS and lead to a treatment dose distribution which is clinically equivalent to the one calculated by the TPS. This procedure can be used as an IMRT QA and further development could allow this technique to be used for other radiotherapy techniques like tomotherapy or volumetric modulated arc therapy.
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Rheumatoid arthritis is the only secondary cause of osteoporosis that is considered independent of bone density in the FRAX(®) algorithm. Although input for rheumatoid arthritis in FRAX(®) is a dichotomous variable, intuitively, one would expect that more severe or active disease would be associated with a greater risk for fracture. We reviewed the literature to determine if specific disease parameters or medication use could be used to better characterize fracture risk in individuals with rheumatoid arthritis. Although many studies document a correlation between various parameters of disease activity or severity and decreased bone density, fewer have associated these variables with fracture risk. We reviewed these studies in detail and concluded that disability measures such as HAQ (Health Assessment Questionnaire) and functional class do correlate with clinical fractures but not morphometric vertebral fractures. One large study found a strong correlation with duration of disease and fracture risk but additional studies are needed to confirm this. There was little evidence to correlate other measures of disease such as DAS (disease activity score), VAS (visual analogue scale), acute phase reactants, use of non-glucocorticoid medications and increased fracture risk. We concluded that FRAX(®) calculations may underestimate fracture probability in patients with impaired functional status from rheumatoid arthritis but that this could not be quantified at this time. At this time, other disease measures cannot be used for fracture prediction. However only a few, mostly small studies addressed other disease parameters and further research is needed. Additional questions for future research are suggested.
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The reliable and objective assessment of chronic disease state has been and still is a very significant challenge in clinical medicine. An essential feature of human behavior related to the health status, the functional capacity, and the quality of life is the physical activity during daily life. A common way to assess physical activity is to measure the quantity of body movement. Since human activity is controlled by various factors both extrinsic and intrinsic to the body, quantitative parameters only provide a partial assessment and do not allow for a clear distinction between normal and abnormal activity. In this paper, we propose a methodology for the analysis of human activity pattern based on the definition of different physical activity time series with the appropriate analysis methods. The temporal pattern of postures, movements, and transitions between postures was quantified using fractal analysis and symbolic dynamics statistics. The derived nonlinear metrics were able to discriminate patterns of daily activity generated from healthy and chronic pain states.
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Ami, ou ennemi, le soleil ? Qui n'a jamais maudit un petit excès de bain de soleil sanctionné par une peau brûlée ? Mais en hiver, quand il se fait rare, l'huile de foie de morue est la panacée que prescrit la sagesse de nos grands-mères pour remplacer la vitamine D qu'en temps normal il nous aide à synthétiser. Pour pouvoir faire le point sur les dangers et les bénéfices du rayonnement solaire, il faut connaître son intensité et en particulier celle du rayonnement ultraviolet (UV) qui a une forte influence sur la santé.Durant ces dernières décades, une forte augmentation des cancers de la peau a été constatée dans les pays développés. La communauté médicale suppose que cette augmentation est liée à une plus forte exposition aux UV, qui serait elle-même due à des changements d'habitudes de la population (engouement pour les loisirs en plein air, pour les vacances sous les tropiques, popularité du bronzage, etc.) et éventuellement à un accroissement du rayonnement UV. [Auteurs]
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Question: Outdoor occupational exposure could be associated with important cumulative and intense exposure to ultraviolet (UV) solar radiation. Such exposure would increase risk of skin cancer. However, little information exists on jobs associated with intense UV exposure. The objective of this study was to characterise occupational UV exposure in a representative sample in France. Methods: A population-based survey was conducted in May-June 2012 through computer-assisted telephonic interviews in population 25 to 69 years of age. Individual UV irradiation was computed with declared time and place of residence matched to UV records from satellite measurement (Eurosun project). We analysed factors influencing exposure to UV (annual average and seasonal peak). Results: A total of 1442 individuals declared having an occupational exposure to UV which represents 18% of population aged 25 to 69 years. Outdoor workers were more frequently men (58%), aged 40-54 (43%), with a phototype III or IV (69%). Occupations associated with highest UV exposure were: construction workers (annual daily average 62.8 Joules/m2), gardeners (62.6), farmers (52.8), culture/art/social sciences workers (52.0) and transport workers/mail carriers (49.5). The maximum of UVA exposure was found for occupation with a strong seasonality of exposure: culture, art or social sciences works (98.1 Joules/m2), construction works (97.2), gardening (96.7) and farming (95.0). Significant factors associated with high occupational UV exposure were gender (men vs. women: 53.6 vs. 42.6), phototype (IV vs. I: 51.9 vs. 45.5) and taking lunch outdoors (always vs. never: 59.8 vs. 48.6). Conclusion: Our study showed that some occupations were associated with particularly intense UV exposure such as farmers, gardeners, construction workers. Other unexpected occupations were also associated with high UV exposure such as transport workers, mail carriers and culture/art/social sciences workers.
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There has been relatively little change over recent decades in the methods used in research on self-reported delinquency. Face-to-face interviews and selfadministered interviews in the classroom are still the predominant alternatives envisaged. New methods have been brought into the picture by recent computer technology, the Internet, and an increasing availability of computer equipment and Internet access in schools. In the autumn of 2004, a controlled experiment was conducted with 1,203 students in Lausanne (Switzerland), where "paper-and-pencil" questionnaires were compared with computer-assisted interviews through the Internet. The experiment included a test of two different definitions of the (same) reference period. After the introductory question ("Did you ever..."), students were asked how many times they had done it (or experienced it), if ever, "over the last 12 months" or "since the October 2003 vacation". Few significant differences were found between the results obtained by the two methods and for the two definitions of the reference period, in the answers concerning victimisation, self-reported delinquency, drug use, failure to respond (missing data). Students were found to be more motivated to respond through the Internet, take less time for filling out the questionnaire, and were apparently more confident of privacy, while the school principals were less reluctant to allow classes to be interviewed through the Internet. The Internet method also involves considerable cost reductions, which is a critical advantage if self-reported delinquency surveys are to become a routinely applied method of evaluation, particularly so in countries with limited resources. On balance, the Internet may be instrumental in making research on self-reported delinquency far more feasible in situations where limited resources so far have prevented its implementation.
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The purpose of this study is to introduce and describe a newly developed index using foot pressure analysis to quantify the degree of equinus gait in children with cerebral palsy before and after injection with botulinum toxin. Data were captured preinjection and 12 weeks postinjection. Ten children aged 2(1/2) to 6(1/2) years took part (5 boys and 5 girls). Three of them had a diagnosis of spastic diplegia and 7 of congenital hemiplegia. In total, 13 limbs were analyzed. After orientation and segmentation of raw pedobarographic data, we determined a dynamic foot pressure index graded 0 to 100 that quantified the relative degree of heel and forefoot contact during stance. These data were correlated (Pearson correlation) with clinical measurements of dorsiflexion at the ankle (on a slow and fast stretch) and video observation (using the Observational Gait Scale). Pedobarograph data were strongly correlated with both the Observational Gait Scale scores (R = 0.79, P < 0.005) and clinical measurements of dorsiflexion on a fast stretch, which is reflective of spasticity (R = 0.70, P < 0.005). We demonstrated the index's sensitivity in detecting changes in spasticity and good correlation with video observations seems to indicate this technique's potential validity. When manipulated and segmented appropriately, and with the development of a simple ordinal index, we found that foot pressure data provided a useful tool in tracking changes in patients with spastic equinus.
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Question: Outdoor workers can be exposed to intense ultraviolet (UV) solar radiation likely to results to sunburns. As sunburn is an important risk factor for skin cancer, in particular melanoma, we investigated the causes of occupational sunburns (OS) in French outdoor workers. Methods: A population-based survey was conducted in May-June 2012 through computer-assisted telephonic interviews in population 25 to 69 years of age. History of sunburn from occupational exposure within the year preceding interview was collected. We analysed the risk of OS in multivariate logistic regression. Results: Out of 1442 individuals who declared having an occupational exposure to solar UV radiation, 403 (27.9%) reported a sunburn from occupational exposure in the year preceding the interview. Sunburns were more frequent in women (30% vs. 26.4% in men although not significant p = 0.14), in younger workers (p = 0.0099), in sensitive phototype (40% in phototype I/II vs. 23% in phototype III/IV, p < 0.001) and in workers taking lunch outdoor (p = 0.0355). Some occupations were more associated with OS (more than 30%): health occupations, managing, research/engineering, construction workers and culture/art/social sciences workers. In multivariate analysis, risk factors for OS are phototype (I vs. IV, OR = 4.30 95% CI [2.65-6.98]), sunburn during leisure time (OR = 3.46 95% CI [2.62-4.59]), seasonality of exposure (seasonal vs. constant exposure OR = 1.36 95% CI [1.02-1.81] and annual UVA exposure (OR for 10J/m² daily average increment 1.08 95% CI [1.02-1.14]). In multivariate analysis the type of occupation was not associated with increased OS. Conclusion: Sunburns from occupation was also observed in non sensitive population, phototype IV, which shows that outdoor workers are potentially exposed to intense UV radiations. This study suggests that prevention should target UV sensitive outdoor workers as well as those cumulating intense UV exposure.
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OBJECTIVES: The purpose of this study was to assess the effectiveness of a novel radiation-independent aiming device for distal locking of intramedullary nails in a human cadaver model. METHODS: A new targeting system was used in 25 intact human cadaver femora for the distal locking procedure after insertion of an intramedullary nail. The number of successful screw placements and the time needed for this locking procedure were recorded. The accuracy of the aiming process was evaluated by computed tomography. RESULTS: The duration of the distal locking process was 8.0 ± 1.8 minutes (mean ± SD; range, 4-11 minutes). None of the screw placements required fluoroscopic guidance. Computed tomography revealed high accuracy of the locking process. The incidence angle (α) of the locking screws through the distal locking holes of the nail was 86.8° ± 5.0° (mean ± SD; range, 80°-96°). Targeting failed in 1 static locking screw because of a material defect in the drilling sleeve. CONCLUSIONS: This cadaver study indicated that an aiming arm-based targeting device is highly reliable and accurate. The promising results suggest that it will help to decrease radiation exposure compared with the traditional "free-hand technique."
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The best indirect evidence that increased bone turnover contributes to fracture risk is the fact that most of the proven therapies for osteoporosis are inhibitors of bone turnover. The evidence base that we can use biochemical markers of bone turnover in the assessment of fracture risk is somewhat less convincing. This relates to natural variability in the markers, problems with the assays, disparity in the statistical analyses of relevant studies and the independence of their contribution to fracture risk. More research is clearly required to address these deficiencies before biochemical markers might contribute a useful independent risk factor for inclusion in FRAX(®).
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Risk factors for fracture can be purely skeletal, e.g., bone mass, microarchitecture or geometry, or a combination of bone and falls risk related factors such as age and functional status. The remit of this Task Force was to review the evidence and consider if falls should be incorporated into the FRAX® model or, alternatively, to provide guidance to assist clinicians in clinical decision-making for patients with a falls history. It is clear that falls are a risk factor for fracture. Fracture probability may be underestimated by FRAX® in individuals with a history of frequent falls. The substantial evidence that various interventions are effective in reducing falls risk was reviewed. Targeting falls risk reduction strategies towards frail older people at high risk for indoor falls is appropriate. This Task Force believes that further fracture reduction requires measures to reduce falls risk in addition to bone directed therapy. Clinicians should recognize that patients with frequent falls are at higher fracture risk than currently estimated by FRAX® and include this in decision-making. However, quantitative adjustment of the FRAX® estimated risk based on falls history is not currently possible. In the long term, incorporation of falls as a risk factor in the FRAX® model would be ideal.
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BACKGROUND: To compare morphological gross tumor volumes (GTVs), defined as pre- and postoperative gadolinium enhancement on T1-weighted magnetic resonance imaging to biological tumor volumes (BTVs), defined by the uptake of (18)F fluoroethyltyrosine (FET) for the radiotherapy planning of high-grade glioma, using a dedicated positron emission tomography (PET)-CT scanner equipped with three triangulation lasers for patient positioning. METHODS: Nineteen patients with malignant glioma were included into a prospective protocol using FET PET-CT for radiotherapy planning. To be eligible, patients had to present with residual disease after surgery. Planning was performed using the clinical target volume (CTV = GTV union or logical sum BTV) and planning target volume (PTV = CTV + 20 mm). First, the interrater reliability for BTV delineation was assessed among three observers. Second, the BTV and GTV were quantified and compared. Finally, the geometrical relationships between GTV and BTV were assessed. RESULTS: Interrater agreement for BTV delineation was excellent (intraclass correlation coefficient 0.9). Although, BTVs and GTVs were not significantly different (p = 0.9), CTVs (mean 57.8 +/- 30.4 cm(3)) were significantly larger than BTVs (mean 42.1 +/- 24.4 cm(3); p < 0.01) or GTVs (mean 38.7 +/- 25.7 cm(3); p < 0.01). In 13 (68%) and 6 (32%) of 19 patients, FET uptake extended >or= 10 and 20 mm from the margin of the gadolinium enhancement. CONCLUSION: Using FET, the interrater reliability had excellent agreement for BTV delineation. With FET PET-CT planning, the size and geometrical location of GTVs and BTVs differed in a majority of patients.