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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Proceedings of the Second PHANToM User's Group Workshop

Salisbury, J. Kenneth, Srinivasan, Mandayam A. 01 December 1997 (has links)
On October 19-22, 1997 the Second PHANToM Users Group Workshop was held at the MIT Endicott House in Dedham, Massachusetts. Designed as a forum for sharing results and insights, the workshop was attended by more than 60 participants from 7 countries. These proceedings report on workshop presentations in diverse areas including rigid and compliant rendering, tool kits, development environments, techniques for scientific data visualization, multi-modal issues and a programming tutorial.
2

Phantom Graphs

Lloyd, Philip 16 March 2012 (has links) (PDF)
No description available.
3

Effects of hypnosis in the treatment of residual stump pain and phantom limb pain

Rickard, Julie Ann, January 2004 (has links) (PDF)
Thesis (Ph. D.)--Washington State University. / Includes bibliographical references.
4

Phantom Graphs

Lloyd, Philip 16 March 2012 (has links)
No description available.
5

The phantom limb

Freed, Murray January 1951 (has links)
Thesis (M.D.)—Boston University
6

Phantom antropomórfico para treinamento de biópsia de tireoide guiada por ultrassom / Anthropomorphic phantom for training of ultrasound-guided biopsy

Grillo, Felipe Wilker 30 September 2015 (has links)
O câncer de tireoide é um dos mais comuns da região da cabeça e pescoço. Atualmente, o método mais eficaz no diagnóstico de lesões da tireoide é a técnica de biópsia conhecida por punção aspirativa por agulha fina (PAAF) guiada por ultrassom. As imagens de ultrassom são utilizadas como guia para inserção de uma agulha fina até a região da lesão, onde são retirados fragmentos de tecido para análise microscópica. O sucesso dos procedimentos de biópsias está diretamente ligado a experiência do médico desde guiar a agulha à lesão até a preparação das lâminas para análise microscópica. O treinamento médico proporciona, durante a realização dos procedimentos, maior confiança ao médico e maior conforto ao paciente. No entanto o número de pacientes disponíveis, bem como o estágio de graduação do profissional, limitam o número de treinamentos realizados. Com base nessas limitações, esse estudo teve por objetivo o desenvolvimento de um phantom de tireoide permitirá que os treinamentos sejam realizados em qualquer horário e local, minimizando a responsabilidade de alunos e professores. Phantoms para ultrassom, geralmente, são corpos de prova construídos para mimetizar propriedades mecânicas e acústicas dos tecidos biológicos que podem ser utilizados no treinamento de habilidades médicas. Para o desenvolvimento deste modelo, utilizou-se um material a base de hidrocarbonetos de cadeia longa com diferentes concentrações de agentes contraste (pó de vidro, cera de carnaúba, parafina granulada, borracha de silicone). Caracterizou-se amostras de diferentes composições com relação ao módulo elástico, velocidade e atenuação da onda ultrassônica, de modo à atingir valores próximos aos encontrados na literatura para as regiões a serem mimetizadas. Obteve-se valores entre 1385 e 1480 m/s, para velocidade; valores entre 0,4 e 4 dB/cm para atenuação; e uma faixa entre 40 e 750 kPa para o módulo elástico. Ao final da caracterização dos materiais, obteve-se um phantom morfológico de pescoço, contendo a mimetização da tireoide para procedimentos de biópsia de tireoide guiada por ultrassom. / The thyroid cancer is one of the most common of head and neck region. Currently, the most effective method in the diagnosis of thyroid lesions is biopsy technique, known by fine-needle aspiration (FNA) guided by ultrasound. Ultrasound images guides the fine needle insertion into the lesion for sampling and then examined under a microscope. The medical training provides greater confidence to physician and comfort to patient. However, the number of available patients as well as the doctor degree stage limit the number of trainings conducted. Therefore, this study aimed to develop a thyroid phantom to training everywhere at any time, minimizing the students and teachers responsibilities. Ultrasound Phantoms mimics mechanical and acoustic properties of biological tissue and can be used for medical training. To develop the phantom we used a hydrocarbon-based material with different concentrations of contrast agents (glass powder, Carnauba wax, paraffin wax and silicone rubber). We calculated the elastic modulus, velocity and ultrasonic wave attenuation of different mixtures to reach values, as close the literature as possible. Was obtained values from 1385 to 1480 m / s for ultrasound velocity, values from 0.4 to 4 dB/cm for attenuation and a range from 40 to 750 kPa for elastic modulus. This study present an anthropomorphic neck phantom containing the necessary structures for training ultrasound guided biopsy by fine-needle aspiration.
7

Phantom para treinamento de neuronavegação guiada por imagens de ultra-som e de ressonância magnética / Training Phantom For Neuronavigation Guided By Ultrasound and Magnetic Ressonance Imaging.

Lemos, Tenysson Will de 11 September 2008 (has links)
Este trabalho teve como objetivo o desenvolvimento de um phantom de cabeça, com características acústicas e magnéticas equivalentes à do cérebro humano, para a formação de imagens, tanto por ultrasom quanto em ressonância magnética, para uso de treinamento clínico em neuronavegação. Geralmente, nos procedimentos de neurocirurgia, são usadas ambas as modalidades de imagens, sendo a ressonância comumente usada durante o processo préoperatório e, o ultrasom usado durante o procedimento cirúrgico, a fim de localizar a lesão e guiar o ato cirúrgico. Para tanto, o material que mimetiza o tecido cerebral foi desenvolvido a base de gelatina animal e vegetal. Pó de vidro e outras substâncias químicas foram adicionados à gelatina de modo que a atenuação acústica, espalhamento da onda e velocidade acústica ficassem equivalentes ao observado no tecido humano. Para mimetizar o sinal de ressonância magnética, material paramagnético foi adicionado à gelatina de modo que os valores dos tempos de relaxação transversal (T2) e longitudinal (T1) ficassem equivalentes aos observados nos tecidos do cérebro humano. Testes de neuronavegação foram realizados com um sistema desenvolvido no próprio laboratório. Para simular um processo cirúrgico, uma janela de acesso ao tecido cerebral foi criada no lado esquerdo da cabeça. As propriedades acústicas e magnéticas do tecido mimetizador proporcionaram contraste nas imagens de ultrasom e ressonância magnética equivalentes aos observados no tecido do cérebro humano. A morfologia e o tamanho do phantom são equivalentes ao de um cérebro de uma criança de aproximadamente cinco anos. Para avaliar o potencial do phantom como uma ferramenta para treinamento de um processo précirúrgico, foi realizada o préprocessamento e reconstrução 3D do phantom a partir das imagens de ressonância magnética, utilizando um software comercial Brainvoyeger® . / The goal of this work was to make a head phantom that can be used either in Ultrasonography (US) or Magnetic Resonance Imaging (MRI) to be applied as guided training for head surgery in a neuronavigation system. Generally, for neurosurgery procedures, both images modality (US and MRI) are used as guide. MRI images are used for previous evaluation of surgery, for localization of the tumor, choice of window on the head for craniotomy and path into the brain to access the tumor. The ultrasonography of the brain is used during the surgery procedure to guide and control the removal of the tumor. The phantom was developed with mimickingtissue material to generate contrast and intensity in the MRI and US image equivalent to that one obtained in human brain. The base material was made of pork gelatin (Bloom 250). The acoustic properties of this material (velocity, attenuation and Speckle) were controlled adding formaldehyde and glass bids. The magnetic properties (T1 and T2 relaxation) were controlled by adding sodiumEDTA and cupric chloride (CuCl2). The morphology and size of the brain were modeled into a head shell of rubber with size and geometry equivalent to a head of a child of approximately 5 years old. The evaluation of the phantom as tools for neuronavigation training was done simulating a surgery procedure. First, a volume of MRI image of the phantom was acquired using a tomography of 1.5 T (Siemens Vision®). After, using a 3D special sensor coupled to micro convex ultrasound transducer, the ultrasound and MRI image, of a same region, was showed simultaneously using a navigator software developed in the own lab by another student. For this evaluation, a craniotomy was done in the right side of the phantom. The 3D reconstruction of the phantom from MRI images volume was evaluated using commercial software Brainvoyeger®. The size, morphology of the head and the US and MRI image quality 12 of the simulated brain were very close to those ones observed in the brain of a young person. This product is very useful as a tool for training neurosurgeons and for calibration of neuronavegator system.
8

Phantom antropomórfico para treinamento de biópsia de tireoide guiada por ultrassom / Anthropomorphic phantom for training of ultrasound-guided biopsy

Felipe Wilker Grillo 30 September 2015 (has links)
O câncer de tireoide é um dos mais comuns da região da cabeça e pescoço. Atualmente, o método mais eficaz no diagnóstico de lesões da tireoide é a técnica de biópsia conhecida por punção aspirativa por agulha fina (PAAF) guiada por ultrassom. As imagens de ultrassom são utilizadas como guia para inserção de uma agulha fina até a região da lesão, onde são retirados fragmentos de tecido para análise microscópica. O sucesso dos procedimentos de biópsias está diretamente ligado a experiência do médico desde guiar a agulha à lesão até a preparação das lâminas para análise microscópica. O treinamento médico proporciona, durante a realização dos procedimentos, maior confiança ao médico e maior conforto ao paciente. No entanto o número de pacientes disponíveis, bem como o estágio de graduação do profissional, limitam o número de treinamentos realizados. Com base nessas limitações, esse estudo teve por objetivo o desenvolvimento de um phantom de tireoide permitirá que os treinamentos sejam realizados em qualquer horário e local, minimizando a responsabilidade de alunos e professores. Phantoms para ultrassom, geralmente, são corpos de prova construídos para mimetizar propriedades mecânicas e acústicas dos tecidos biológicos que podem ser utilizados no treinamento de habilidades médicas. Para o desenvolvimento deste modelo, utilizou-se um material a base de hidrocarbonetos de cadeia longa com diferentes concentrações de agentes contraste (pó de vidro, cera de carnaúba, parafina granulada, borracha de silicone). Caracterizou-se amostras de diferentes composições com relação ao módulo elástico, velocidade e atenuação da onda ultrassônica, de modo à atingir valores próximos aos encontrados na literatura para as regiões a serem mimetizadas. Obteve-se valores entre 1385 e 1480 m/s, para velocidade; valores entre 0,4 e 4 dB/cm para atenuação; e uma faixa entre 40 e 750 kPa para o módulo elástico. Ao final da caracterização dos materiais, obteve-se um phantom morfológico de pescoço, contendo a mimetização da tireoide para procedimentos de biópsia de tireoide guiada por ultrassom. / The thyroid cancer is one of the most common of head and neck region. Currently, the most effective method in the diagnosis of thyroid lesions is biopsy technique, known by fine-needle aspiration (FNA) guided by ultrasound. Ultrasound images guides the fine needle insertion into the lesion for sampling and then examined under a microscope. The medical training provides greater confidence to physician and comfort to patient. However, the number of available patients as well as the doctor degree stage limit the number of trainings conducted. Therefore, this study aimed to develop a thyroid phantom to training everywhere at any time, minimizing the students and teachers responsibilities. Ultrasound Phantoms mimics mechanical and acoustic properties of biological tissue and can be used for medical training. To develop the phantom we used a hydrocarbon-based material with different concentrations of contrast agents (glass powder, Carnauba wax, paraffin wax and silicone rubber). We calculated the elastic modulus, velocity and ultrasonic wave attenuation of different mixtures to reach values, as close the literature as possible. Was obtained values from 1385 to 1480 m / s for ultrasound velocity, values from 0.4 to 4 dB/cm for attenuation and a range from 40 to 750 kPa for elastic modulus. This study present an anthropomorphic neck phantom containing the necessary structures for training ultrasound guided biopsy by fine-needle aspiration.
9

Simulation and Analysis of Human Phantoms Exposed to Heavy Charged Particle Irradiations Using the Particle and Heavy Ion Transport System (PHITS)

Lee, Dongyoul 2011 December 1900 (has links)
Anthropomorphic phantoms are commonly used for testing radiation fields without the need to expose human subjects. One of the most widely known is RANDO phantom. This phantom is used primarily for medical X-ray applications, but a similar design known as "MATROSHKA" is now being used for space research and exposed to heavy ion irradiations from the Galactic environment. Since the radiation field in the phantom should respond in a similar manner to how it would act in human tissues and organs under an irradiation, the tissue substitute chosen for soft tissue and the level of complexity of the entire phantom are crucial issues. The phantoms, and the materials used to create them, were developed mainly for photon irradiations and have not been heavily tested under the conditions of heavy ion exposures found in the space environment or external radiotherapy. The Particle and Heavy-Ion Transport code System (PHITS) was used to test the phantoms and their materials for their potential as human surrogates for heavy ion irradiation. Stopping powers and depth-dose distributions of heavy charged particles (HCPs) important to space research and medical applications were first used in the simulations to test the suitability of current soft tissue substitutes. A detailed computational anthropomorphic phantom was then developed where tissue substitutes and ICRU-44 tissue could be interchanged to verify the validation of the soft tissue substitutes and and determine the required level of complexity of the entire phantom needed to achieve a specified precision as a replacement of the human body. The materials tested were common soft tissue substitutes in use and the materials which had a potential for the soft tissue substitute. Ceric sulfate dosimeter solution was closest to ICRU-44 tissue; however, it was not appropriate as the phantom material because it was a solution. A150 plastic, ED4C (fhw), Nylon (Du Pont Elvamide 8062), RM/SR4, Temex, and RW-2 were within 1% of the mean normalized difference of mass stopping powers (or stopping powers for RW-2) when compared to the ICRU-44 tissue, and their depth-dose distributions were close; therefore, they were the most suitable among the remaining solid materials. Overall, the soft tissue substitutes which were within 1% of ICRU-44 tissue in terms of stopping power produced reasonable results with respect to organ dose in the developed phantom. RM/SR4 is the best anthropomorphic phantom soft tissue substitute because it has similar interaction properties and identical density with ICRU-44 tissue and it is a rigid solid polymer giving practical advantages in manufacture of real phantoms.
10

Phantom para treinamento de neuronavegação guiada por imagens de ultra-som e de ressonância magnética / Training Phantom For Neuronavigation Guided By Ultrasound and Magnetic Ressonance Imaging.

Tenysson Will de Lemos 11 September 2008 (has links)
Este trabalho teve como objetivo o desenvolvimento de um phantom de cabeça, com características acústicas e magnéticas equivalentes à do cérebro humano, para a formação de imagens, tanto por ultrasom quanto em ressonância magnética, para uso de treinamento clínico em neuronavegação. Geralmente, nos procedimentos de neurocirurgia, são usadas ambas as modalidades de imagens, sendo a ressonância comumente usada durante o processo préoperatório e, o ultrasom usado durante o procedimento cirúrgico, a fim de localizar a lesão e guiar o ato cirúrgico. Para tanto, o material que mimetiza o tecido cerebral foi desenvolvido a base de gelatina animal e vegetal. Pó de vidro e outras substâncias químicas foram adicionados à gelatina de modo que a atenuação acústica, espalhamento da onda e velocidade acústica ficassem equivalentes ao observado no tecido humano. Para mimetizar o sinal de ressonância magnética, material paramagnético foi adicionado à gelatina de modo que os valores dos tempos de relaxação transversal (T2) e longitudinal (T1) ficassem equivalentes aos observados nos tecidos do cérebro humano. Testes de neuronavegação foram realizados com um sistema desenvolvido no próprio laboratório. Para simular um processo cirúrgico, uma janela de acesso ao tecido cerebral foi criada no lado esquerdo da cabeça. As propriedades acústicas e magnéticas do tecido mimetizador proporcionaram contraste nas imagens de ultrasom e ressonância magnética equivalentes aos observados no tecido do cérebro humano. A morfologia e o tamanho do phantom são equivalentes ao de um cérebro de uma criança de aproximadamente cinco anos. Para avaliar o potencial do phantom como uma ferramenta para treinamento de um processo précirúrgico, foi realizada o préprocessamento e reconstrução 3D do phantom a partir das imagens de ressonância magnética, utilizando um software comercial Brainvoyeger® . / The goal of this work was to make a head phantom that can be used either in Ultrasonography (US) or Magnetic Resonance Imaging (MRI) to be applied as guided training for head surgery in a neuronavigation system. Generally, for neurosurgery procedures, both images modality (US and MRI) are used as guide. MRI images are used for previous evaluation of surgery, for localization of the tumor, choice of window on the head for craniotomy and path into the brain to access the tumor. The ultrasonography of the brain is used during the surgery procedure to guide and control the removal of the tumor. The phantom was developed with mimickingtissue material to generate contrast and intensity in the MRI and US image equivalent to that one obtained in human brain. The base material was made of pork gelatin (Bloom 250). The acoustic properties of this material (velocity, attenuation and Speckle) were controlled adding formaldehyde and glass bids. The magnetic properties (T1 and T2 relaxation) were controlled by adding sodiumEDTA and cupric chloride (CuCl2). The morphology and size of the brain were modeled into a head shell of rubber with size and geometry equivalent to a head of a child of approximately 5 years old. The evaluation of the phantom as tools for neuronavigation training was done simulating a surgery procedure. First, a volume of MRI image of the phantom was acquired using a tomography of 1.5 T (Siemens Vision®). After, using a 3D special sensor coupled to micro convex ultrasound transducer, the ultrasound and MRI image, of a same region, was showed simultaneously using a navigator software developed in the own lab by another student. For this evaluation, a craniotomy was done in the right side of the phantom. The 3D reconstruction of the phantom from MRI images volume was evaluated using commercial software Brainvoyeger®. The size, morphology of the head and the US and MRI image quality 12 of the simulated brain were very close to those ones observed in the brain of a young person. This product is very useful as a tool for training neurosurgeons and for calibration of neuronavegator system.

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