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PURPOSE: This study aimed to evaluate a new therapeutic option for the spasticity using ultrasound neuromodulation in an animal model of spastic cerebral palsy. METHODS: Thirty-two adult male Wistar rats were randomly distributed in: negative control (NC); positive control (PC); untreated model (UTM); and treated model (TM). Rats in the control groups received sham surgery, and rats in the model groups received the spastic cerebral palsy model surgery. The rats' motor functions were evaluated by the Rotarod and CatWalk tests before and after surgery. PC and TM groups underwent ultrasonic neuromodulation by a physiotherapeutic ultrasound (intensity 0.1 W/cm2, at 1 MHz) continuous mode for 5 seconds, for seven days. RESULTS: Twelve rats showed a spastic pattern (UTM = 6 and TM = 6), motor limitations (UTM = 6 and TM = 6), and ten had difficulty feeding (UTM = 5 and TM = 5). One UTM group rat could not recover its preoperative latency time, while the other rats in the model groups did. The speed at which the limbs swung reduced after surgery and increased in subsequent assessments, demonstrating greater instability and a deficit in locomotion balance. CONCLUSIONS: Results were not yet sufficient to assert ultrasound neuromodulation as a possible therapy for spasticity in spastic cerebral palsy in the parameters used, and more studies are necessary.

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ABSTRACT Purpose: This study aimed to evaluate a new therapeutic option for the spasticity using ultrasound neuromodulation in an animal model of spastic cerebral palsy. Methods: Thirty-two adult male Wistar rats were randomly distributed in: negative control (NC); positive control (PC); untreated model (UTM); and treated model (TM). Rats in the control groups received sham surgery, and rats in the model groups received the spastic cerebral palsy model surgery. The rats' motor functions were evaluated by the Rotarod and CatWalk tests before and after surgery. PC and TM groups underwent ultrasonic neuromodulation by a physiotherapeutic ultrasound (intensity 0.1 W/cm2, at 1 MHz) continuous mode for 5 seconds, for seven days. Results: Twelve rats showed a spastic pattern (UTM = 6 and TM = 6), motor limitations (UTM = 6 and TM = 6), and ten had difficulty feeding (UTM = 5 and TM = 5). One UTM group rat could not recover its preoperative latency time, while the other rats in the model groups did. The speed at which the limbs swung reduced after surgery and increased in subsequent assessments, demonstrating greater instability and a deficit in locomotion balance. Conclusions: Results were not yet sufficient to assert ultrasound neuromodulation as a possible therapy for spasticity in spastic cerebral palsy in the parameters used, and more studies are necessary.

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BACKGROUND AND OBJECTIVE: The improvement in the appearance of the skin with dermal striae (DS) is currently eval-uated by invasive methods, such as biopsy. This study evaluates whether high-resolution ultrasound (HRUS) could be used to identify skin lesions in vivo caused by DS, using 2D images and measuring the thickness of the dermal layer. METHODS: High-resolution ultrasound at frequencies of 20 and 30 MHz was used in this study in ten volunteers with DS. The thickness of the skin layers was estimated by tracing five vertical lines from epidermis (EP) to dermis (DE) and DE to hypodermis (H) surface. RESULTS: The dermal lesions caused by striae appeared in ultrasonic images as poor echo areas. The average normal DE thickness varied from 1.07 to 1.65 mm, while the DE thickness with DS varied between 0.35 and 1.33 mm. A statistically significant reduction in the DE thickness was found (P-value < .05) in the presence of DS. The mean values of the EP thickness without and with DS were 0.12 ± 0.03 mm and 0.11 ± 0.02 mm, respec-tively. A total of 90.00% of the EP-related groups did not present the normal distribu-tion (P-value < .05). CONCLUSIONS: High-resolution ultrasound permitted the visualization of the three skin layers and the dermal lesions caused by striae. The dermal layer thicknesses with striae were thinner than those without. Therefore, ultrasound 2D imaging has shown to be a promising and financially feasible tool to be used as a noninvasive diagnostic method for evaluating therapeutic protocols used in the treatment of these dermal conditions.

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ABSTRACT Objective: This work evaluates the relationship between ultrasonic reflection and bone density from fourteen cylindrical bovine cortical bone samples (3.0-cm thick). Methods: Twenty US reflection signals per sample were acquired along the bone surface (2.0-mm step). The Integrated Reflection Coefficient (IRC) from each signal was compared to Quantitative Computed Tomography (QCT). Results: Seven IRC and QCT curves presented Pearson's Correlation R-values above 0.5. For weak correlation curves, QCT and IRC showed similar trends in several segments. Conclusion: IRC was sensitive to bone density variation. Level of Evidence: Experimental Study, Investigating a Diagnostic Test.

RESUMO Objetivo: Este estudo avalia a relação entre a reflexão ultrassônica e a densidade óssea de 14 amostras cilíndricas de osso cortical bovino (3,0 cm de espessura). Métodos: Foi realizada a aquisição de 20 sinais de reflexão ultrassônica por amostra (passo de 2,0 mm), ao longo da superfície óssea. O Coeficiente de Reflexão Integrado (IRC) de cada sinal foi comparado por Tomografia Computadorizada Quantitativa (QCT). Resultados: Sete curvas de IRC e QCT apresentaram valor de Correlação R de Pearson acima de 0,5. Para curvas de correlação fraca, QCT e IRC apresentaram tendências semelhantes em vários segmentos. Conclusão: O IRC foi sensível à variação da densidade óssea. Nível de evidência: Estudo Experimental, Investigação de Exame Diagnóstico.

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O presente trabalho descreve o projeto e construção de um calorímetro diferencial com a finalidade de avaliar o aquecimento gerado por feixes ultrassônicos em níveis terapêuticos. O calorímetro consiste em duas câmaras cilíndricas de alumínio idênticas (de medição e de referência), preenchidas com um material mimetizador de tecido biológico (phantom). Cada câmara possui seis termopares tipo E (diâmetro 0,24 mm), posicionados ao longo do eixo central de propagação da onda, entre as profundidades 10-60 mm, distantes 10 mm entre si. Foi levantada a curva de potência e estimado o valor da área de radiação efetiva (ERA) dos dois transdutores utilizados. A partir destes dados, a intensidade efetiva foi determinada. Para avaliar o calorímetro, foi utilizado um equipamento de ultrassom de Fisioterapia, operando nas frequências nominais 1 e 3 MHz, modo contínuo, intensidades nominais 0,5; 1,0; 1,5 e 2,0 W.cm-2 e tempo de irradiação 180 segundos. Uma sequência de oito protocolos de medição foi realizada dez vezes. Para ambas as frequências, houve um declínio do aquecimento ao longo da profundidade e a região do "phantom" que mais aqueceu foi a que corresponde à profundidade de 10 mm, em todas as intensidades. O maior aquecimento ocorreu a 2,0 W.cm-2, com médias de 6,7 ± 1,0 ºC e 12,6 ± 1,2 ºC, a 1 MHz e 3 MHz, respectivamente. O calorímetro proposto mostrou-se útil na caracterização de feixes ultrassônicos aplicados em Fisioterapia, principalmente na identificação de possíveis máximos locais de temperatura (pontos quentes) que ocorrem ao longo do eixo principal do feixe.

The present work describes the project and construction of a differential calorimeter designed to evaluate the heating generated by ultrasound beam in therapeutic levels. The calorimeter consists of two identical aluminum cylindrical chambers (for measurement and reference) filled with biological tissue mimicking material (phantom). Each chamber is fitted with six thermocouples type E (0.24 mm diameter) disposed along the wave propagation central axis, between the depths of 10-60 mm, distant 10 mm from each other. The power curve and the value of the effective radiation area (ERA) of the two transducers were estimated. From these data, the effective intensity was determined. The calorimeter was tested by using an ultrasound equipment of Physiotherapy, operating at the frequencies 1 and 3 MHz, continuous mode, nominal intensities 0.5, 1.0, 1.5 and 2.0 W.cm-2 and irradiation time 180 seconds. A sequence of eight protocols of measurement was repeated 10 times. At both frequencies, there was a decline of heating along the depth and the phantom region that heated the most corresponded to 10 mm of depth, in all intensities employed. The greatest increase in temperature occurred after application of 2.0 W.cm-2, with averages of 6.7 ± 1.0 ºC and 12.6 ± 1.2 ºC, at 1 MHz and 3 MHz, respectively. The proposed calorimeter may be useful for identifying possible local temperature maxima (hot spots) that appear along the central axis beam.