998 resultados para Radiology, Medical


Relevância:

20.00% 20.00%

Publicador:

Resumo:

We discuss potential caveats when estimating topologies of 3D brain networks from surface recordings. It is virtually impossible to record activity from all single neurons in the brain and one has to rely on techniques that measure average activity at sparsely located (non-invasive) recording sites Effects of this spatial sampling in relation to structural network measures like centrality and assortativity were analyzed using multivariate classifiers A simplified model of 3D brain connectivity incorporating both short- and long-range connections served for testing. To mimic M/EEG recordings we sampled this model via non-overlapping regions and weighted nodes and connections according to their proximity to the recording sites We used various complex network models for reference and tried to classify sampled versions of the ""brain-like"" network as one of these archetypes It was found that sampled networks may substantially deviate in topology from the respective original networks for small sample sizes For experimental studies this may imply that surface recordings can yield network structures that might not agree with its generating 3D network. (C) 2010 Elsevier Inc All rights reserved

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: To obtain cerebral perfusion territories of the left, the right. and the posterior circulation in humans with high signal-to-noise ratio (SNR) and robust delineation. Materials and Methods: Continuous arterial spin labeling (CASL) was implemented using a dedicated radio frequency (RF) coil. positioned over the neck, to label the major cerebral feeding arteries in humans. Selective labeling was achieved by flow-driven adiabatic fast passage and by tilting the longitudinal labeling gradient about the Y-axis by theta = +/- 60 degrees. Results: Mean cerebral blood flow (CBF) values in gray matter (GM) and white matter (WM) were 74 +/- 13 mL center dot 100 g(-1) center dot minute(-1) and 14 +/- 13 mL center dot 100 g(-1) center dot minute(-1), respectively (N = 14). There were no signal differences between left and right hemispheres when theta = 0 degrees (P > 0.19), indicating efficient labeling of both hemispheres. When theta = +60 degrees, the signal in GM on the left hemisphere, 0.07 +/- 0.06%, was 92% lower than on the right hemisphere. 0.85 +/- 0.30% (P < 1 x 10(-9)). while for theta = -60 degrees, the signal in the right hemisphere. 0.16 +/- 0.13%, was 82% lower than on the contralateral side. 0.89 +/- 0.22% (P < 1 x 10(-10)). Similar attenuations were obtained in WM. Conclusion: Clear delineation of the left and right cerebral perfusion territories was obtained, allowing discrimination of the anterior and posterior circulation in each hemisphere.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: We present an iterative framework for CT reconstruction from transmission ultrasound data which accurately and efficiently models the strong refraction effects that occur in our target application: Imaging the female breast. Methods: Our refractive ray tracing framework has its foundation in the fast marching method (FNMM) and it allows an accurate as well as efficient modeling of curved rays. We also describe a novel regularization scheme that yields further significant reconstruction quality improvements. A final contribution is the development of a realistic anthropomorphic digital breast phantom based on the NIH Visible Female data set. Results: Our system is able to resolve very fine details even in the presence of significant noise, and it reconstructs both sound speed and attenuation data. Excellent correspondence with a traditional, but significantly more computationally expensive wave equation solver is achieved. Conclusions: Apart from the accurate modeling of curved rays, decisive factors have also been our regularization scheme and the high-quality interpolation filter we have used. An added benefit of our framework is that it accelerates well on GPUs where we have shown that clinical 3D reconstruction speeds on the order of minutes are possible.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Modern medical imaging techniques enable the acquisition of in vivo high resolution images of the vascular system. Most common methods for the detection of vessels in these images, such as multiscale Hessian-based operators and matched filters, rely on the assumption that at each voxel there is a single cylinder. Such an assumption is clearly violated at the multitude of branching points that are easily observed in all, but the Most focused vascular image studies. In this paper, we propose a novel method for detecting vessels in medical images that relaxes this single cylinder assumption. We directly exploit local neighborhood intensities and extract characteristics of the local intensity profile (in a spherical polar coordinate system) which we term as the polar neighborhood intensity profile. We present a new method to capture the common properties shared by polar neighborhood intensity profiles for all the types of vascular points belonging to the vascular system. The new method enables us to detect vessels even near complex extreme points, including branching points. Our method demonstrates improved performance over standard methods on both 2D synthetic images and 3D animal and clinical vascular images, particularly close to vessel branching regions. (C) 2008 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Data mining is a relatively new field of research that its objective is to acquire knowledge from large amounts of data. In medical and health care areas, due to regulations and due to the availability of computers, a large amount of data is becoming available [27]. On the one hand, practitioners are expected to use all this data in their work but, at the same time, such a large amount of data cannot be processed by humans in a short time to make diagnosis, prognosis and treatment schedules. A major objective of this thesis is to evaluate data mining tools in medical and health care applications to develop a tool that can help make rather accurate decisions. In this thesis, the goal is finding a pattern among patients who got pneumonia by clustering of lab data values which have been recorded every day. By this pattern we can generalize it to the patients who did not have been diagnosed by this disease whose lab values shows the same trend as pneumonia patients does. There are 10 tables which have been extracted from a big data base of a hospital in Jena for my work .In ICU (intensive care unit), COPRA system which is a patient management system has been used. All the tables and data stored in German Language database.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Many countries recognized the potential of medicaltourism as an alternative source of economic growth. Especially after theeconomic crisis many Asian countries joined medical tourism in hopes to escapethe severe financial difficulty. However, yet only few countries have managedto become a famous medical tourism destination. With growing number ofcompetitors, newly joined countries of medical tourism, face the difficulty inintroducing them self as attractive medical tourism destination. South Koreaas a new medical tourism destination, should consider what to offer to themedical tourists to attract them. The aim of the thesis was to investigate aspects influencing the participationof medical tourists to discover how South Korea could develop anattractive medical tourism destination. After examining the casestudy and results from the text analysis, researcher reached to the conclusionthat quality, cost and accessibility to treatment are the major reasons toparticipate in medical tourism. Also in the fierce competition, it is importantto develop differentiated offers from other destinations. Therefore, Koreashould concentrate on specialized treatments and ICT system to become anattractive medical tourism destination.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The World Health Organisation suggests that simplification of the medical abortion regime will contribute to an increased acceptability of medical abortion, among women as well as providers. It is expected that a home-based follow-up after a medical abortion will increase the willingness to opt for medical abortion as well as decrease the workload and service costs in the clinic. Trial design The study is a randomised, controlled, non-superiority trial . Methods Women screened to participate in the study are those with unwanted pregnancies and gestational ages equal to or less than nine weeks. Eligible women randomised to the home-based assessment group will use a low-sensitivity pregnancy test and a pictorial instruction sheet at home, while the women in the clinic follow-up group will return to the clinic for routine follow-up carried out by a doctor. The primary objective of the study is to evaluate the effectiveness of home-based assessment using a low-sensitivity pregnancy test and a pictorial instruction sheet 10-14 days after an early medical abortion. Providers or research assistants will not be blinded during outcome assessment. To ensure feasibility of the self-assessment intervention an adaption phase took place at the selected study sites before study initiation. This was to optimise and tailor-make the intervention and the study procedures and resulted in the development of the pictorial instruction sheet for how to use the low-sensitivity pregnancy test and the danger signs after a medical abortion. Discussion In this paper, we will describe the study protocol for a randomised control trial investigating the efficacy of simplified follow-up in terms of home-based assessment, 10-14 days after a medical abortion. Moreover, a description of the adaptation phase is included for a better understanding of the implementation of the intervention in a setting where literacy is low and the road-connections are poor. Trial registration: Clinicaltrials.gov NCT01827995. Registered 04 May 2013

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Studies evaluating acceptability of simplified follow-up after medical abortion have focused on high-resource or urban settings where telephones, road connections, and modes of transport are available and where women have formal education. Objective: To investigate women's acceptability of home-assessment of abortion and whether acceptability of medical abortion differs by in-clinic or home-assessment of abortion outcome in a low-resource setting in India. Design: Secondary outcome of a randomised, controlled, non-inferiority trial. Setting Outpatient primary health care clinics in rural and urban Rajasthan, India. Population: Women were eligible if they sought abortion with a gestation up to 9 weeks, lived within defined study area and agreed to follow-up. Women were ineligible if they had known contraindications to medical abortion, haemoglobin < 85mg/l and were below 18 years. Methods: Abortion outcome assessment through routine clinic follow-up by a doctor was compared with home-assessment using a low-sensitivity pregnancy test and a pictorial instruction sheet. A computerized random number generator generated the randomisation sequence (1: 1) in blocks of six. Research assistants randomly allocated eligible women who opted for medical abortion (mifepristone and misoprostol), using opaque sealed envelopes. Blinding during outcome assessment was not possible. Main outcome measures: Women's acceptability of home-assessment was measured as future preference of follow-up. Overall satisfaction, expectations, and comparison with previous abortion experiences were compared between study groups. Results: 731 women were randomized to the clinic follow-up group (n = 353) or home-assessment group (n = 378). 623 (85%) women were successfully followed up, of those 597 (96%) were satisfied and 592 (95%) found the abortion better or as expected, with no difference between study groups. The majority, 355 (57%) women, preferred home-assessment in the event of a future abortion. Significantly more women, 284 (82%), in the home-assessment group preferred home-assessment in the future, as compared with 188 (70%) of women in the clinic follow-up group, who preferred clinic follow-up in the future (p < 0.001). Conclusion: Home-assessment is highly acceptable among women in low-resource, and rural, settings. The choice to follow-up an early medical abortion according to women's preference should be offered to foster women's reproductive autonomy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Unsafe abortions are estimated to cause eight per-cent of maternal mortality in India. Lack of providers, especially in rural areas, is one reason unsafe abortions take place despite decades of legal abortion. Education and training in reproductive health services has been shown to influence attitudes and increase chances that medical students will provide abortion care services in their future practice. To further explore previous findings about poor attitudes toward abortion among medical students in Maharastra, India, we conducted in-depth interviews with medical students in their final year of education. METHOD: We used a qualitative design conducting in-depth interviews with twenty-three medical students in Maharastra applying a topic guide. Data was organized using thematic analysis with an inductive approach. RESULTS: The participants described a fear to provide abortion in their future practice. They lacked understanding of the law and confused the legal regulation of abortion with the law governing gender biased sex selection, and concluded that abortion is illegal in Maharastra. The interviewed medical students' attitudes were supported by their experiences and perceptions from the clinical setting as well as traditions and norms in society. Medical abortion using mifepristone and misoprostol was believed to be unsafe and prohibited in Maharastra. The students perceived that nurse-midwives were knowledgeable in Sexual and Reproductive Health and many found that they could be trained to perform abortions in the future. CONCLUSIONS: To increase chances that medical students in Maharastra will perform abortion care services in their future practice, it is important to strengthen their confidence and knowledge through improved medical education including value clarification and clinical training.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objectives. This study aimed to investigate the knowledge, attitudes and perceptionstowards contraceptive use and counselling among medical students in Maharashtra, India. Setting. Considerable global maternal mortality and morbidity could be avoided through theuse of effective contraception. In India, contraception services are frequently unavailable or there are obstacles to obtaining modern, reversible contraceptives. Participants. A cross-sectional descriptive study using a self-administered questionnaire was conducted among 1996 medical students in their fifth year of study at 27 medical colleges in the state of Maharashtra, India. Descriptive and analytical statistics interpreted the survey instrument and significant results were presented with 95% CI. Results. Respondents expressed a desire to provide contraceptive services. A few studentshad experienced training in abortion care. There were misconceptions about moderncontraceptive methods and the impact of sex education. Attitudes towards contraceptionwere mainly positive, premarital counselling was supported and the influence of traditional values and negative provider attitudes on services was recognised. Gender, area of upbringing and type of medical college did not change the results. Conclusions. Despite mostly positive attitudes towards modern contraceptives, sex education and family planning counselling, medical students in Maharashtra have misconceptions about modern methods of contraception. Preservice and in-service training in contraceptive counselling should be implemented in order to increase women's access to evidence-based maternal healthcare services.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: The need for multiple clinical visits remains a barrier to women accessing safe legal medical abortion services. Alternatives to routine clinic follow-up visits have not been assessed in rural low-resource settings. We compared the effectiveness of standard clinic follow-up versus home assessment of outcome of medical abortion in a low-resource setting. Methods: This randomised, controlled, non-inferiority trial was done in six health centres (three rural, three urban) in Rajasthan, India. Women seeking early medical abortion up to 9 weeks of gestation were randomly assigned (1:1) to either routine clinic follow-up or self-assessment at home. Randomisation was done with a computer-generated randomisation sequence, with a block size of six. The study was not blinded. Women in the home-assessment group were advised to use a pictorial instruction sheet and take a low-sensitivity urine pregnancy test at home, 10-14 days after intake of mifepristone, and were contacted by a home visit or telephone call to record the outcome of the abortion. The primary (non-inferiority) outcome was complete abortion without continuing pregnancy or need for surgical evacuation or additional mifepristone and misoprostol. The non-inferiority margin for the risk difference was 5%. All participants with a reported primary outcome and who followed the clinical protocol were included in the analysis. This study is registered with ClinicalTrials.gov, number NCT01827995. Findings: Between April 23, 2013, and May 15, 2014, 731 women were recruited and assigned to clinic follow-up (n=366) or home assessment (n=365), of whom 700 were analysed for the main outcomes (n=336 and n=364, respectively). Complete abortion without continuing pregnancy, surgical intervention, or additional mifepristone and misoprostol was reported in 313 (93%) of 336 women in the clinic follow-up group and 347 (95%) of 364 women in the home-assessment group (difference -2.2%, 95% CI -5.9 to 1.6). One case of haemorrhage occurred in each group (rate of adverse events 0.3% in each group); no other adverse events were noted. Interpretation Home assessment of medical abortion outcome with a low-sensitivity urine pregnancy test is non-inferior to clinic follow-up, and could be introduced instead of a clinic follow-up visit in a low-resource setting.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Current legislation does not permit the administration of first line resuscitation medications by suitably qualified Division 1 registered nurses (RNs) in the absence of a medical officer. This omission by the Drugs,  Poisons and Controlled Substances Act 1981 (Vic) and the Drugs, Poisons and The Controlled Substances Regulations 1995 (Vic) leaves many critical care nurses in a vulnerable legal position.

The primary aim of this study was to gauge the view of critical care nurses with respect to lobbying for change to the current legislation. In addition, the study aimed to explore and describe the educational preparation, practice perceptions and experiences of RNs working in critical care regarding cardiopulmonary resuscitation and the administration of first line advanced life support (ALS) medications in the absence of a medical officer. It was anticipated that data collected would demonstrate some of the dilemmas associated with the initiation and administration of ALS medications for practising critical care nurses and could be used to inform controlling bodies in order for them to gain an appreciation of the issues facing critical care nurses during resuscitation.

A mailout survey was sent to all members of the Victorian Branch of the Australian College of Critical Care Nurses (ACCCN). The results showed that the majority of nurses underwent an annual ALS assessment and had current ALS accreditation. Nurses indicated that they felt educationally prepared and were confident to manage cardiopulmonary resuscitation without a medical officer; indeed, the majority had done so. The differences in practice issues for metropolitan, regional and rural nurses were highlighted. There is therefore clear evidence to suggest that legislative amendments are appropriate and necessary, given the time critical nature of cardiopulmonary arrest. There was overwhelming support for ACCCN Vic. Ltd to lobby the Victorian government for changes to the law.