377 resultados para Arteries Radiography

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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Atherosclerosis is a serious chronic disease, responsible for thousands of deaths worldwide and is characterized by thickening and loss of elasticity of the arterial walls, associated with the presence of atheromatous plaques. Various risk factors act directly on predisposition to the disease, among which the following are pointed out: diabetes mellitus, arterial hypertension and inadequate diet and eating habits. More recent researches have elucidated new risk factors acting in the development of this disease, such as, for example: periodontitis, chronic renal disease and menopause. The panoramic radiograph, commonly used in dental practice, makes it possible to see calcified atherosclerotic plaques that are eventually deposited in the carotid arteries. The aim of this review article was to emphasize the dentist's important role in the detection of carotid artery atheromas in panoramic radiographs and the immediate referral of patients affected by these calcifications to doctors. In addition, the study intended to guide the dentist, especially the dental radiologist, with regard to differential diagnosis, which should be made taking into consideration particularly the triticeal cartilage when it is calcified. © Henriques et al.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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This study assessed the effects of a single intracoronary injection of autologous stem cells on the cardiac function of dogs with Chagas cardiomyopathy. Bone-marrow-derived stem cells were delivered into the right and left coronary arteries of 5 mature dogs with mildly compromised cardiac function due to chronic Chagas cardiomyopathy. Blood pressure and electrocardiographic and echocardiographic parameters were recorded at monthly intervals for 6 mo in the 3 dogs that survived. Although no changes were observed in the electrocardiogram and blood pressure, there was a significant increase in peak velocity of aortic flow 3 mo after stem cell transplantation. Pre-ejection period, isovolumic relaxation time, and the Tei index of myocardial performance were reduced significantly 4 mo after the procedure. All significant changes persisted to the end of the study. The results suggest that the transplantation of autologous bone-marrow-derived stem cells into the coronary arteries of dogs with Chagas cardiomyopathy may have a beneficial effect but the small number of dogs studied was a limitation.

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O trajeto das artérias coronárias foi estudado no cervo-do-pantanal para comparação com os ruminantes domésticos. A artéria coronária esquerda se origina na aorta, na superfície auricular cardíaca e divide-se em ramos paraconal e circunflexo, os quais preenchem o sulco paraconal interventricular e sulco subsinuoso, respectivamente; esta artéria também origina um ramo para o conus arteriosus imediatamente antes de entrar no miocárdio. A artéria coronária direita surge da aorta, na borda cranial cardíaca e termina nesta borda, próximo ao sulco subsinuoso interventricular, entretanto, sem preenche-lo.

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Digital radiography in the inspection of welded pipes to be installed under deep water offshore gas and oil pipelines, like a presalt in Brazil, in the paper has been investigated. The aim is to use digital radiography for nondestructive testing of welds as it is already in use in the medical, aerospace, security, automotive, and petrochemical sectors. Among the current options, the DDA (Digital Detector Array) is considered as one of the best solutions to replace industrial films, as well as to increase the sensitivity to reduce the inspection cycle time. This paper shows the results of this new technique, comparing it to radiography with industrial films systems. In this paper, 20 test specimens of longitudinal welded pipe joints, specially prepared with artificial defects like cracks, lack of fusion, lack of penetration, and porosities and slag inclusions with varying dimensions and in 06 different base metal wall thicknesses, were tested and a comparison of the techniques was made. These experiments verified the purposed rules for parameter definitions and selections to control the required digital radiographic image quality as described in the draft international standard ISO/DIS 10893-7. This draft is first standard establishing the parameters for digital radiography on weld seam of welded steel pipes for pressure purposes to be used on gas and oil pipelines.

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Aim. Duplex scanning has been used in the evaluation of the aorta and proximal arteries of the lower extremities, but has limitations in evaluating the arteries of the leg. The utilization of ultrasonographic contrast (USC) may be helpful in improving the quality of the image in these arteries. The objective of the present study was to verify whether the USC increases the diagnostic accuracy of patency of the leg arteries and if it diminishes the time needed to perform duplex scanning.Methods. Twenty patients with critical ischemia (20 lower extremities) were examined by standard duplex scanning, duplex scanning with contrast and digital subtraction arteriography (DSA). The 3 arteries of the leg were divided into 3 segments, for a total of 9 segments per limb. Each segment was evaluated for patency in order to compare the 3 diagnostic methods. Comparison was made between standard duplex scanning and duplex scanning with contrast in terms of quality of the color-coded Doppler signal and of the spectral curve, and also of the time to perform the exams.Results. Duplex scanning with contrast was similar to arteriography in relation to patency diagnosis (p>0.3) and even superior in some of the segments. Standard duplex scanning was inferior to arteriography and to duplex scanning with contrast (p<0.001). There were improvements of 70% in intensity of the color-coded Doppler signal and 76% in the spectral curve after the utilization of contrast. The time necessary to perform the examinations was 23.7 minutes for standard duplex scanning and 16.9 minutes for duplex scanning with contrast (p<0.001).Conclusion. The use of ultrasonographic contrast increased the accuracy of the diagnosis of patency of leg arteries and diminished the time necessary for the execution of duplex scanning.

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A anastomose arterial término-terminal é demorada, requer tempo prolongado de oclusão vascular e esta associada a necrose focal, infiltração leucocitária e, conseqüentemente, à fibrose e calcificação da parede arterial. A cola de fibrina é uma alternativa para a anastomose microvascular e pode evitar estas alterações com menor aderência aos tecidos vizinhos e melhor coaptação das bordas arteriais. OBJETIVO: Comparar o processo cicatricial de anastomoses convencionais com anastomoses feitas com cola de fibrina em artérias maiores. MÉTODOS: em 22 coelhos, ambas carótidas foram seccionadas transversalmente e reconstruídas por meio de anastomose término-terminal com 4 pontos simples de reparo e cola de fibrina de um lado (G1), e com 8 pontos separados do outro lado (G2). Após 3 e 15 dias, os animais foram destinados aleatoriamente para estudo de força tênsil concentração de hidroxiprolina (8 animais) e avaliação histológica das anastomoses (3 animais). As lâminas histológicas foram coradas pelo HE Masson e Picrossirius polarização (PSP). RESULTADOS: Após 3 e 15 dias a força tênsil aumenta em ambos os grupos, de 280,0± 32,6g para 432,2± 131,2g no Grupo 1 e de 221,4± 72,4g para 452,2± 132,0g no Grupo 2; sem diferença estatística entre os grupos em cada período. A concentração de hidroxiprolina expressa como razão hidroxiprolina/proteína, variou de 0,0816± 0,0651 para 0,0622± 0,0184 no Grupo 1 e de 0,0734± 0,0577 para 0,0460± 0,0271 no Grupo 2; sem diferença estatística entre os períodos e grupos. Os estudos histológicos mostraram discreto aumento das reações de inflamação e reparação no Grupo 2. A técnica PSP mostrou predomínio do colágeno tipo I em relação do colágeno tipo II nas anastomoses de ambos os grupos, sem diferença expressiva entre esses grupos. CONCLUSÃO: A anastomose com a cola de fibrina foi menos lesiva para a parede arterial do que a anastomose convencional. Mesmo usando menos pontos, as características de força tênsil e de cicatrização da anastomose com cola de fibrina foram similares em ambos os grupos. Os tempos de realização das anastomoses foram significativamente maiores do que na anastomose convencional.

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Background: Accurate early diagnosis of lung metastases is important for establishing therapeutic measures. Therefore, the present study aimed to compare survey thoracic radiographs and computerized tomography (CT) scans to specifically identify lung metastases in female dogs with mammary tumors.Methods: Twenty-one female dogs, weighing 3 to 34 kg and aged from 5 years to 14 years and 10 months, with mammary tumors were studied. In all dogs before the imaging examinations, fine-needle aspiration cytology of the mammary tumors was performed to confirm the diagnosis. Three-view thoracic radiographs were accomplished: right lateral, left lateral and ventrodorsal views. Sequential transverse images of the thorax were acquired on a spiral Scanner, before and after intravenous bolus injection of nonionic iodine contrast. Soft-tissue and lung windows were applied. All the mammary tumors were surgically removed and examined histologically.Results: The correlation between the cytological and histological results regarding presence of malignancy was observed in only 17 cases. In radiographic examinations, no dog displayed signs of lung metastases or thorax chest lesions. CT detected lung metastasis in two cases, while small areas of lung atelectasis located peripherally were found in 28.57% of the dogs.Conclusion: In this study population, spiral CT showed higher sensitivity than chest radiographies to detect lung metastasis; this indicates that CT should be performed on all female dogs with malignant mammary tumors.

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In the present experimental study we assessed induced osteoarthritis data in rabbits, compared three diagnostic methods, i.e., radiography (XR), computed tomography (CT) and magnetic resonance imaging (MRI), and correlated the imaging findings with those obtained by macroscopic evaluation. Ten young female rabbits of the Norfolk breed were used. Seven rabbits had the right knee immobilized in extension for a period of 12 weeks (immobilized group), and three others did not have a limb immobilized and were maintained under the same conditions (control group). Alterations observed by XR, CT and MRI after the period of immobilization were osteophytes, osteochondral lesions, increase and decrease of joint space, all of them present both in the immobilized and non-immobilized contralateral limbs. However, a significantly higher score was obtained for the immobilized limbs (XT: P = 0.016, CT: P = 0.031, MRI: P = 0.0156). All imaging methods were able to detect osteoarthritis changes after the 12 weeks of immobilization. Macroscopic evaluation identified increased thickening of joint capsule, proliferative and connective tissue in the femoropatellar joint, and irregularities of articular cartilage, especially in immobilized knees. The differences among XR, CT and MRI were not statistically significant for the immobilized knees. However, MRI using a 0.5 Tesla scanner was statistically different from CT and XR for the non-immobilized contralateral knees. We conclude that the three methods detected osteoarthritis lesions in rabbit knees, but MRI was less sensitive than XR and CT in detecting lesions compatible with initial osteoarthritis. Since none of the techniques revealed all the lesions, it is important to use all methods to establish an accurate diagnosis.

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Purpose: the purpose of this in vivo study was to compare the accuracy of primary incisor length determined by direct digital radiography (straight-line measurement and grid superimposition) and measurement of the actual tooth length. Methods. Twenty-two primary maxillary incisors that required extractions were selected from 3- to 5-year-old children. The teeth were radiographed with an intraoral sensor using the long cone technique and a sensor holder (30-cm focus-to-sensor distance). The exposure time was 03 seconds. Tooth length was estimated by using straight-line and grid measurements provided by the distance measurement feature of the Computed Dental Radiography digital dental imaging system. The actual tooth length was obtained by measuring the extracted tooth with G digital caliper. Data were analyzed statistically by Pearson's correlation coefficient and a paired t test. Results: There were statistically significant differences (P=.007) between the 2 measurement techniques and between the actual tooth lengths and grid measurements. There was no statistically significant difference (P=38) between straight-line measurements and actual tooth lengths, showing that the straight-line measurements were more accurate. Underestimation of the actual tooth length, however, occurred in 45% of the straight-line measurements and in 73% of the grid measurements. Conclusion: It is possible to determine primary tooth length in digital radiographs using onscreen measurements with 0 reasonable degree of accuracy.

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Objective: The objective of this study was to evaluate the influence of homeopathic treatment with comfrey (Shymphytum officinalis 6CH) on radiographic bone density and area around titanium implants.Material and methods: Forty-eight rats were divided into two groups of 24 animals each: a control group (C) and a test group (SO). Each animal received one titanium micro-implant placed in the tibia. The animals in Group SO were subjected to 10 drops of comfrey 6CH per day mixed into their drinking water until the day of sacrifice. Eight animals of each group were sacrificed at 7, 14 and 28 days post-surgery, respectively.Standardized digital radiographs were obtained on the day of implant installation (baseline images) and on the day of sacrifice (final images). Digital subtraction of the two corresponding images was performed to evaluate changes in bone density and the area related to change around the implant between baseline and final images.Results: Subtraction images demonstrated that a significant difference existed in mean shade of gray at 14 days post-surgery between Group SO (mean 175.3 +/- 14.4) and Group C (mean 146.2 +/- 5.2). Regarding the area in pixels corresponding to the bone gain in Group SO, the differences observed between the sacrifice periods and groups were only significant at 7 days sacrifice between Group SO (mean 171.2 +/- 21.9) and Group C (mean 64.5 +/- 60.4).Conclusion: Within the limits of this study, comfrey administration promotes an increase in radiographic bone density around titanium implants in the initial period of bone healing.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)