974 resultados para Instabilidade cervical
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PURPOSE: Statistical shape and appearance models play an important role in reducing the segmentation processing time of a vertebra and in improving results for 3D model development. Here, we describe the different steps in generating a statistical shape model (SSM) of the second cervical vertebra (C2) and provide the shape model for general use by the scientific community. The main difficulties in its construction are the morphological complexity of the C2 and its variability in the population. METHODS: The input dataset is composed of manually segmented anonymized patient computerized tomography (CT) scans. The alignment of the different datasets is done with the procrustes alignment on surface models, and then, the registration is cast as a model-fitting problem using a Gaussian process. A principal component analysis (PCA)-based model is generated which includes the variability of the C2. RESULTS: The SSM was generated using 92 CT scans. The resulting SSM was evaluated for specificity, compactness and generalization ability. The SSM of the C2 is freely available to the scientific community in Slicer (an open source software for image analysis and scientific visualization) with a module created to visualize the SSM using Statismo, a framework for statistical shape modeling. CONCLUSION: The SSM of the vertebra allows the shape variability of the C2 to be represented. Moreover, the SSM will enable semi-automatic segmentation and 3D model generation of the vertebra, which would greatly benefit surgery planning.
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PURPOSE: To meta-analyze the literature on the clinical performance of Class V restorations to assess the factors that influence retention, marginal integrity, and marginal discoloration of cervical lesions restored with composite resins, glass-ionomer-cement-based materials [glass-ionomer cement (GIC) and resin-modified glass ionomers (RMGICs)], and polyacid-modified resin composites (PMRC). MATERIALS AND METHODS: The English literature was searched (MEDLINE and SCOPUS) for prospective clinical trials on cervical restorations with an observation period of at least 18 months. The studies had to report about retention, marginal discoloration, marginal integrity, and marginal caries and include a description of the operative technique (beveling of enamel, roughening of dentin, type of isolation). Eighty-one studies involving 185 experiments for 47 adhesives matched the inclusion criteria. The statistical analysis was carried out by using the following linear mixed model: log (-log (Y /100)) = β + α log(T ) + error with β = log(λ), where β is a summary measure of the non-linear deterioration occurring in each experiment, including a random study effect. RESULTS: On average, 12.3% of the cervical restorations were lost, 27.9% exhibited marginal discoloration, and 34.6% exhibited deterioration of marginal integrity after 5 years. The calculation of the clinical index was 17.4% of failures after 5 years and 32.3% after 8 years. A higher variability was found for retention loss and marginal discoloration. Hardly any secondary caries lesions were detected, even in the experiments with a follow-up time longer than 8 years. Restorations placed using rubber-dam in teeth whose dentin was roughened showed a statistically significantly higher retention rate than those placed in teeth with unprepared dentin or without rubber-dam (p < 0.05). However, enamel beveling had no influence on any of the examined variables. Significant differences were found between pairs of adhesive systems and also between pairs of classes of adhesive systems. One-step self-etching had a significantly worse clinically index than two-step self-etching and three-step etch-and-rinse (p = 0.026 and p = 0.002, respectively). CONCLUSION: The clinical performance is significantly influenced by the type of adhesive system and/or the adhesive class to which the system belongs. Whether the dentin/enamel is roughened or not and whether rubberdam isolation is used or not also significantly influenced the clinical performance. Composite resin restorations placed with two-step self-etching and three-step etch-and-rinse adhesive systems should be preferred over onestep self-etching adhesive systems, GIC-based materials, and PMRCs.
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OBJETIVO: Avaliar, radiograficamente, o efeito da tração manual sobre o comprimento da coluna cervical. MATERIAIS E MÉTODOS: Cinqüenta e cinco participantes de ambos os gêneros - 12 masculinos (22%) e 43 femininos (78%) - sem história de distúrbios cervicais contituíram a amostra deste estudo. Eles foram submetidos a dois procedimentos radiológicos, um antes e outro durante a tração manual sustentada por 120 segundos. As distâncias entre as bordas anteriores e posteriores da segunda à sétima vértebras cervicais foram mensuradas e comparadas antes e durante a tração manual. RESULTADOS: A mediana da distância anterior antes da tração foi de 8,40 cm e durante a tração aumentou para 8,50 cm (p=0,002). A mediana da distância posterior antes da tração foi de 8,35 cm e durante a tração aumentou para 8,50 cm (p<0,001). CONCLUSÃO: Os resultados demonstraram que a aplicação da tração manual promoveu aumento estatisticamente significante do comprimento da coluna cervical em indivíduos assintomáticos.
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HIV-infected women are at increased risk of cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC), but it has been difficult to disentangle the influences of heavy exposure to HPV infection, inadequate screening and immunodeficiency. A case-control study including 364 CIN2/3 and 20 ICC cases matched to 1,147 controls was nested in the Swiss HIV Cohort Study (1985-2013). CIN2/3 risk was significantly associated with low CD4+ cell counts, whether measured as nadir [odds ratio (OR) per 100-cell/μL decrease = 1.15, 95% CI: 1.08, 1.22], or at CIN2/3 diagnosis (1.10, 95% CI: 1.04, 1.16). An association was evident even for nadir CD4+ 200-349 versus ≥350 cells/μL (OR = 1.57, 95% CI: 1.09, 2.25). After adjustment for nadir CD4+, a protective effect of >2-year cART use was seen against CIN2/3 (OR versus never cART use = 0.64, 95% CI: 0.42, 0.98). Despite low study power, similar associations were seen for ICC, notably with nadir CD4+ (OR for 50 vs. >350 cells/μL= 11.10, 95% CI: 1.24, 100). HPV16-L1 antibodies were significantly associated with CIN2/3, but HPV16-E6 antibodies were nearly exclusively detected in ICC. In conclusion, worsening immunodeficiency, even at only moderately decreased CD4+ cell counts, is a significant risk factor for CIN2/3 and cervical cancer.
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PFAPA syndrome represents the most common cause of recurrent fever in children in European populations, and it is characterized by recurrent episodes of high fever, pharyngitis, cervical adenitis, and aphthous stomatitis. Many possible causative factors have been explored so far, including infectious agents, immunologic mechanisms and genetic predisposition, but the exact etiology remains unclear. Recent findings demonstrate a dysregulation of different components of innate immunity during PFAPA flares, such as monocytes, neutrophils, complement, and pro-inflammatory cytokines, especially IL-1β, suggesting an inflammasome-mediated innate immune system activation and supporting the hypothesis of an autoinflammatory disease. Moreover, in contrast with previous considerations, the strong familial clustering suggests a potential genetic origin rather than a sporadic disease. In addition, the presence of variants in inflammasome-related genes, mostly in NLRP3 and MEFV, suggests a possible role of inflammasome-composing genes in PFAPA pathogenesis. However, none of these variants seem to be relevant, alone, to its etiology, indicating a high genetic heterogeneity as well as an oligogenic or polygenic genetic background.
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BACKGROUND: To compare the prognostic value of different anatomical and functional metabolic parameters determined using [(18)F]FDG-PET/CT with other clinical and pathological prognostic parameters in cervical cancer (CC). METHODS: Thirty-eight patients treated with standard curative doses of chemo-radiotherapy (CRT) underwent pre- and post-therapy [(18)F]FDG-PET/CT. [(18)F]FDG-PET/CT parameters including mean tumor standardized uptake values (SUV), metabolic tumor volume (MTV) and tumor glycolytic volume (TGV) were measured before the start of CRT. The post-treatment tumor metabolic response was evaluated. These parameters were compared to other clinical prognostic factors. Survival curves were estimated by using the Kaplan-Meier method. Cox regression analysis was performed to determine the independent contribution of each prognostic factor. RESULTS: After 37 months of median follow-up (range, 12-106), overall survival (OS) was 71 % [95 % confidence interval (CI), 54-88], disease-free survival (DFS) 61 % [95 % CI, 44-78] and loco-regional control (LRC) 76 % [95 % CI, 62-90]. In univariate analyses the [(18)F]FDG-PET/CT parameters unfavorably influencing OS, DFS and LRC were pre-treatment TGV-cutoff ≥562 (37 vs. 76 %, p = 0.01; 33 vs. 70 %, p = 0.002; and 55 vs. 83 %, p = 0.005, respectively), mean pre-treatment tumor SUV cutoff ≥5 (57 vs. 86 %, p = 0.03; 36 vs. 88 %, p = 0.004; 65 vs. 88 %, p = 0.04, respectively) and a partial tumor metabolic response after treatment (9 vs. 29 %, p = 0.0008; 0 vs. 83 %, p < 0.0001; 22 vs. 96 %, p < 0.0001, respectively). After multivariate analyses a partial tumor metabolic response after treatment remained as an independent prognostic factor unfavorably influencing DFS and LRC (RR 1:7.7, p < 0.0001, and RR 1:22.6, p = 0.0003, respectively) while the pre-treatment TGV-cutoff ≥562 negatively influenced OS and DFS (RR 1:2, p = 0.03, and RR 1:2.75, p = 0.05). CONCLUSIONS: Parameters capturing the pre-treatment glycolytic volume and metabolic activity of [(18)F]FDG-positive disease provide important prognostic information in patients with CC treated with CRT. The post-therapy [(18)F]FDG-PET/CT uptake (partial tumor metabolic response) is predictive of disease outcome.
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Study design: A retrospective study of image guided cervical implant placement precision. Objective: To describe a simple and precise classification of cervical critical screw placement. Summary of Background Data: "Critical" screw placement is defined as implant insertion into a bone corridor which is surrounded circumferentially by neurovascular structures. While the use of image guidance has improved accuracy, there is currently no classification which provides sufficient precision to assess the navigation success of critical cervical screw placement. Methods: Based on postoperative clinical evaluation and CT imaging, the orthogonal view evaluation method (OVEM) is used to classify screw accuracy into grade I (no cortical breach), grade la (screw thread cortical breach), grade II (internal diameter cortical breach) and grade III (major cortical breach causing neural or vascular injury). Grades II and III are considered to be navigation failures, after accounting for bone corridor / screw mismatch (minimal diameter of targeted bone corridor being smaller than an outer screw diameter). Results: A total of 276 screws from 91 patients were classified into grade I (64.9%), grade la (18.1%), and grade II (17.0%). No grade III screw was observed. The overall rate of navigation failure was 13%. Multiple logistic regression indicated that navigational failure was significantly associated with the level of instrumentation and the navigation system used. Navigational failure was rare (1.6%) when the margin around the screw in the bone corridor was larger than 1.5 mm. Conclusions: OVEM evaluation appears to be a useful tool to assess the precision of critical screw placement in the cervical spine. The OVEM validity and reliability need to be addressed. Further correlation with clinical outcomes will be addressed in future studies.
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To understand the natural history of cervical human papillomavirus (HPV)-infections, more information is needed on their genotype-specific prevalence, acquisition, clearance, persistence and progression. This thesis is part of the prospective Finnish Family HPV study. 329 pregnant women (mean age 25.5 years) were recruited during the third trimester of pregnancy and were followed up for 6 years. The outcomes of cervical HPV infections were evaluated among all the mothers participating in the study. Generalized estimating equation (GEE)-models and Poisson regression were used to estimate the risk factors of type-specific acquisition, clearance, persistence and progression of Species 7 and 9 HPV-genotypes. Independent protective factors against incident infections were higher number of life-time sexual partners, initiation of oral contraceptive use after age 20 years and becoming pregnant during FU. Older age and negative oral HR-HPV DNA status at baseline were associated with increased clearance, whereas higher number of current sexual partners decreased the probability of clearance. Early onset of smoking, practicing oral sex and older age increased the risk of type-specific persistence, while key predictors of CIN/SIL were persistent HR-HPV, abnormal Pap smear and new sexual partners. HPV16, together with multiple-type infections were the most frequent incident genotypes, most likely to remain persistent and least likely to clear. Collectively, LR-HPV types showed shorter incidence and clearance times than HR-HPV types. In multivariate models, different predictors were associated with these main viral outcomes, and there is some tentative evidence to suggest that oral mucosa might play a role in controlling some of these outcomes.
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O tratamento dos ferimentos de hipofaringe ainda é controvertido na literatura. A maior parte dos autores acredita que o tratamento preferencial consiste na exploração cirúrgica imediata, com reparo primário da lesão e drenagem ou somente a drenagem, e que o tratamento conservador estaria indicado em casos selecionados. Entre 157 ferimentos cervicais penetrantes, num período de quatro anos, encontramos sete (4,4%) casos de perfuração de hipofaringe. Destes, seis (85,7%) foram tratados cirurgicamente, cinco (71 ,4%) com sutura primária e drenagem. A taxa de mortalidade foi nula e a morbidade foi de 28,6%, sendo de 11,2 dias o tempo médio de internação.
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O encontro de fatores preditivos de metástase cervical seria de grande valia para o tratamento de pacientes com tumores de alto potencial metastatizante e com pescoço clinicamente negativo. Procuramos encontrar fatores clínicos e histológicos em tumores iniciais de língua e soalho de boca que pudessem indicar a realização de um esvaziamento cervical eletivo.Foram estudados os seguintes fatores: sexo, idade, tabagismo, etilismo, raça, tamanho da lesão, sítio primário, dor, tempo de queixa, primeira queixa, aspecto macroscópico da lesão, infiltrado inflamatório peritumoral, grau de diferenciação da biópsia, desmoplasia, invasão vascular, invasão perineural e número de mitoses por 10 campos de maior aumento. Nenhum dos fatores estudados foi capaz de predizer a ocorrência de metástase cervical no período pré-operatório. Acreditamos que outros fatores devam ser estudados e explorados para que se consiga indicar o esvaziamento cervical eletivo de modo criterioso para o tratamento destas lesões.
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O câncer cérvico-uterino é muito comum em vários países da América Latina. As estatísticas de mortalidade e as taxas de incidência demonstram a sua real importância. O cânver cérvico-uterino freqüentemente é uma doença progressiva iniciada com mudanças intra-epiteliais, que podem se transformar em um processo invasivo, sendo o nosso objetivo tratar precocemente estas lesões quando ainda é possível a cura de 100%. Em nosso estudo prospectivo foram selecionadas 21 pacientes com neoplasia cervical intra-epitelial reatreadas pela citplogia e diagnosticadas pela histopatologia após biópsia dirigida pela colposcopia. O método terapêutico empregado foi a vaporização a laser com o CO2. Tiveram como pré-requisito os seguintes critérios: informação segura pela colposcopia da zona de transformação e afastar a presença de câncer invasivo; a neoplasia epitelial cervical deve ocupar a ectocervix sem nenhuma extensão para o canal cervical e correlação positiva entre a citologia, colposcopia e histologia. O uso de laser CO2 com microscópio permitiu precisão na aplicação e com vantagens de ser um procedimento ambulatorial diminuindo estresse cirúrgico das pacientes. Foi realizado sem anestesia e com duração média de 15 minutos. A cicatrização completou-se em torno de três semanas e com cuidados operatórios mínimos. Somente dois casos tiveram sangramento vaginal discreto no quinto e décimo dia de pós-operatório, resolvido com tamponamento vaginal por 24 horas. A colposcopia, cirurgia e o seguimento foram feitos pelo autor, tendo uma paciente sido submetida a uma segunda vaporização no quinto mês de controle. Somente uma paciente teve recidiva no 26° mês de seguimento e complementará o tratamento. As vinte outras restantes estão em controle sem recidiva de doença. Em vista dos resultados obtivemos um percentual de cura de 95%, que coincide com a literatura. O uso de laser CO2 no tratamento das neoplasias cervicais intra-epiteliais (NIC) ou virais tem sido estimulado como uma alternativa digna de ser seguida pelas seguintes razões: cirurgia de não contato, tratamento rápido e indolor, diminuição das custas da internação; complicações mínimas e sem efeito subseqüente sobre a fertilidade e competência cervical, menor necrose térmica, e possibilidade de novo tratamento ambulatorial. Por estas razões e pelo alto percentual de cura podemos concluir que a cirurgia proposta foi vantajosa para o tratamento da neoplasia cervical intra-epitelial, quando comparada com outros métodos de tratamento.