7 resultados para Multi-Criteria Optimisation
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OBJECTIVES: This study analyzes the results of the arterial switch operation for transposition of the great arteries in member institutions of the European Congenital Heart Surgeons Association. METHODS: The records of 613 patients who underwent primary arterial switch operations in each of 19 participating institutions in the period from January 1998 through December 2000 were reviewed retrospectively. RESULTS: A ventricular septal defect was present in 186 (30%) patients. Coronary anatomy was type A in 69% of the patients, and aortic arch pathology was present in 20% of patients with ventricular septal defect. Rashkind septostomy was performed in 75% of the patients, and 69% received prostaglandin. There were 37 hospital deaths (operative mortality, 6%), 13 (3%) for patients with an intact ventricular septum and 24 (13%) for those with a ventricular septal defect (P < .001). In 36% delayed sternal closure was performed, 8% required peritoneal dialysis, and 2% required mechanical circulatory support. Median ventilation time was 58 hours, and intensive care and hospital stay were 6 and 14 days, respectively. Although of various preoperative risk factors the presence of a ventricular septal defect, arch pathology, and coronary anomalies were univariate predictors of operative mortality, only the presence of a ventricular septal defect approached statistical significance (P = .06) on multivariable analysis. Of various operative parameters, aortic crossclamp time and delayed sternal closure were also univariate predictors; however, only the latter was an independent statistically significant predictor of death. CONCLUSIONS: Results of the procedure in European centers are compatible with those in the literature. The presence of a ventricular septal defect is the clinically most important preoperative risk factor for operative death, approaching statistical significance on multivariable analysis.
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Introduction and hypothesis Puborectalis avulsion is a likely etiological factor for female pelvic organ prolapse(FPOP). We performed a study to establish minimal sonographic criteria for the diagnosis of avulsion. Methods We analysed datasets of 764 women seen at a urogynecological service. Offline analysis of ultrasound datasets was performed blinded to patient data. Tomographic ultrasound imaging (TUI) was used to diagnose avulsion of the puborectalis muscle. Results Logistic regression modelling of TUI data showed that complete avulsion is best diagnosed by requiring the three central tomographic slices to be abnormal. This finding was obtained in 30% of patients and was associated with symptoms and signs of FPOP (P<0.001). Lesser degrees of trauma (‘partial avulsion’) were not associated with symptoms or signs of pelvic floor dysfunction. Conclusions Complete avulsion of the puborectalis muscle is best diagnosed on TUI by requiring all three central slices to be abnormal. Partial trauma seems of limited clinical relevance.
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INTRODUCTION: There is much controversy regarding the current indications and contraindications for digital replantation. PRESENTATION OF CASE: Three patients with absolute contraindications for digital replantation according to classical criteria are presented (Case 1: multilevel amputation of the hand and fingers; Case 3: avulsion of the thumb; Case 4: index amputation proximal to the insertion of the flexor digitorum superficialis). In addition a patient with a very distal digital amputation (Case 2), whose indication for replantation is controversial is also presented. In all cases, the patients were replanted and showed good functional and aesthetical results. DISCUSSION: Most authors advocate that the classical indications for replantation have been validated by experience, are predicated on the potential for long-term function, and should be followed in most if not all cases. However, some surgeons have been adopting a more liberal attitude with good results. CONCLUSION: The clinical cases presented in this paper suggest that the standard criteria for digital replantation should not be followed rigidly but instead should be regarded as a general guide.
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BACKGROUND: Wireless capsule endoscopy has been introduced as an innovative, non-invasive diagnostic technique for evaluation of the gastrointestinal tract, reaching places where conventional endoscopy is unable to. However, the output of this technique is an 8 hours video, whose analysis by the expert physician is very time consuming. Thus, a computer assisted diagnosis tool to help the physicians to evaluate CE exams faster and more accurately is an important technical challenge and an excellent economical opportunity. METHOD: The set of features proposed in this paper to code textural information is based on statistical modeling of second order textural measures extracted from co-occurrence matrices. To cope with both joint and marginal non-Gaussianity of second order textural measures, higher order moments are used. These statistical moments are taken from the two-dimensional color-scale feature space, where two different scales are considered. Second and higher order moments of textural measures are computed from the co-occurrence matrices computed from images synthesized by the inverse wavelet transform of the wavelet transform containing only the selected scales for the three color channels. The dimensionality of the data is reduced by using Principal Component Analysis. RESULTS: The proposed textural features are then used as the input of a classifier based on artificial neural networks. Classification performances of 93.1% specificity and 93.9% sensitivity are achieved on real data. These promising results open the path towards a deeper study regarding the applicability of this algorithm in computer aided diagnosis systems to assist physicians in their clinical practice.
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OBJECTIVE: Intensive image surveillance after endovascular aneurysm repair is generally recommended due to continued risk of complications. However, patients at lower risk may not benefit from this strategy. We evaluated the predictive value of the first postoperative computed tomography angiography (CTA) characteristics for aneurysm-related adverse events as a means of patient selection for risk-adapted surveillance. METHODS: All patients treated with the Low-Permeability Excluder Endoprosthesis (W. L. Gore & Assoc, Flagstaff, Ariz) at a tertiary institution from 2004 to 2011 were included. First postoperative CTAs were analyzed for the presence of endoleaks, endograft kinking, distance from the lowermost renal artery to the start of the endograft, and for proximal and distal sealing length using center lumen line reconstructions. The primary end point was freedom from aneurysm-related adverse events. Multivariable Cox regression was used to test postoperative CTA characteristics as independent risk factors, which were subsequently used as selection criteria for low-risk and high-risk groups. Estimates for freedom from adverse events were obtained using Kaplan-Meier survival curves. RESULTS: Included were 131 patients. The median follow-up was 4.1 years (interquartile range, 2.1-6.1). During this period, 30 patients (23%) sustained aneurysm-related adverse events. Seal length <10 mm and presence of endoleak were significant risk factors for this end point. Patients were subsequently categorized as low-risk (proximal and distal seal length ≥10 mm and no endoleak, n = 62) or high-risk (seal length <10 mm or presence of endoleak, or both; n = 69). During follow-up, four low-risk patients (3%) and 26 high-risk patients (19%) sustained events (P < .001). Four secondary interventions were required in three low-risk patients, and 31 secondary interventions in 23 high-risk patients. Sac growth was observed in two low-risk patients and in 15 high-risk patients. The 5-year estimates for freedom from aneurysm-related adverse events were 98% for the low-risk group and 52% for the high-risk group. For each diagnosis, 81.7 image examinations were necessary in the low-risk group and 8.2 in the high-risk group. CONCLUSIONS: Our results suggest that the first postoperative CTA provides important information for risk stratification after endovascular aneurysm repair when the Excluder endoprosthesis is used. In patients with adequate seal and no endoleaks, the risk of aneurysm-related adverse events was significantly reduced, resulting in a large number of unnecessary image examinations. Adjusting the imaging protocol beyond 30 days and up to 5 years, based on individual patients' risk, may result in a more efficient and rational postoperative surveillance.
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An increase in the number of new cases of tuberculosis (TB) combined with poor clinical outcome was identified among HIV-infected injecting drug users attending a large HIV unit in central Lisbon. A retrospective epidemiological and laboratory study was conducted to review all newly diagnosed cases of TB from 1995 to 1996 in the HIV unit. Results showed that from 1995 to 1996, 63% (109/173) of the Mycobacterium tuberculosis isolates from HIV-infected patients were resistant to one or more anti-tuberculosis drugs; 89% (95) of these were multidrug-resistant, i.e., resistant to at least isoniazid and rifampicin. Eighty percent of the multidrug-resistant strains (MDR) available for restriction fragment length polymorphism (RFLP) DNA fingerprinting clustered into one of two large clusters. Epidemiological data support the conclusion that the transmission of MDR-TB occurred among HIV-infected injecting drug users exposed to infectious TB cases on open wards in the HIV unit. Improved infection control measures on the HIV unit and the use of empirical therapy with six drugs once patients were suspected to have TB, reduced the incidence of MDR-TB from 42% of TB cases in 1996 to 11% in 1999.
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Existem diversos factores que podem influenciar o prognóstico funcional nos doentes com Acidente Vascular Cerebral (AVC), nomeadamente o hemisfério afectado, severidade do deficit neurológico inicial, presença de comorbilidades, etiologia, entre outros. A idade como factor preditivo na reabilitação destes doentes tem sido alvo de controvérsia. O objectivo deste trabalho foi avaliar a idade como variável preditiva de funcionalidade após AVC. Os autores recolheram retrospectivamente os dados dos processos clínicos dos doentes internados para reabilitação no Serviço de MFR do Hospital de Curry Cabral durante o ano de 2008, tendo como critério de inclusão diagnóstico de AVC. A funcionalidade foi avaliada à entrada e à saída do internamento, com a Medida de Independência Funcional (MIF) e o Índice de Barthel (IB). Os doentes com idade igual ou inferior a 45 anos foram considerados jovens adultos. Foi realizado o emparelhamento de doentes em casos-controlo. Para cada caso de AVC no adulto jovem os critérios de emparelhamento foram: idade> 45 anos, o mesmo tipo de AVC e hemisfério envolvido e igual MIF à entrada (mais ou menos três pontos). Para tratamento estatístico foi utilizado o programa SPSS 13.0. Foram recolhidos dados de 69 doentes com AVC, dos quais 12 foram considerados adultos jovens (38 +-5 anos). Quando comparados com os doentes mais velhos, os adultos jovens saíram com uma MIF maior (101 Vs 88 pontos; p=0,04), sem que se verificassem diferenças estatisticamente significativas em relação a: MIF à entrada, IB à entrada e saída, eficiência da MIF ou duração do internamento. A idade jovem associou-se com um melhor valor de MIF à saída (r=0,33, p=0,006), mesmo quando se controlou para a MIF à entrada (r=0,23, p=0,05). Em relação à análise dos nove pares caso-controlo, não se verificaram diferenças entre os grupos nas medidas de funcionalidade à entrada e à saída, nem na duração do internamento. A idade correlacionou-se com funcionalidade à saída, sendo que os doentes mais jovens saíram mais funcionais. No entanto, na análise caso-controlo, quando se controlou para outras variáveis (e.g. tipo de AVC), a variável perdeu o seu valor preditivo. Estes resultados podem dever-se ao facto de o AVC no jovem adulto ter diferentes características, como um maior número de eventos hemorrágicos. Nesta amostra, os jovens adultos tiveram igual número de AVC isquémicos e hemorrágicos (seis) e o grupo mais velho teve apenas 23% eventos hemorrágicos (p=0,07). É conhecido o melhor prognóstico funcional deste tipo de AVC, quando não associados a mortalidade precoce. Este estudo apresenta algumas limitações: o tamanho da amostra; o facto de a MIF e o IB não serem medidas de funcionalidade desenvolvidas especificamente para doentes com AVC; um viés de selecção, pois somente alguns doentes são incluídos em programa de reabilitação em internamento; o momento de avaliação da funcionalidade residual foi á saída do internamento, apenas algumas semanas pós-AVC. A idade jovem parece associar-se a um melhor prognóstico funcional. Este aspecto pode estar associado ao facto de o AVC nos doentes mais novos ter características diferentes (e.g. maior proporção de AVC hemorrágico), normalmente associadas a uma recuperação mais favorável.