Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
Sci Rep ; 10(1): 9118, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32499539

RESUMO

Intense laser-driven proton pulses, inherently broadband and highly divergent, pose a challenge to established beamline concepts on the path to application-adapted irradiation field formation, particularly for 3D. Here we experimentally show the successful implementation of a highly efficient (50% transmission) and tuneable dual pulsed solenoid setup to generate a homogeneous (laterally and in depth) volumetric dose distribution (cylindrical volume of 5 mm diameter and depth) at a single pulse dose of 0.7 Gy via multi-energy slice selection from the broad input spectrum. The experiments were conducted at the Petawatt beam of the Dresden Laser Acceleration Source Draco and were aided by a predictive simulation model verified by proton transport studies. With the characterised beamline we investigated manipulation and matching of lateral and depth dose profiles to various desired applications and targets. Using an adapted dose profile, we performed a first proof-of-technical-concept laser-driven proton irradiation of volumetric in-vitro tumour tissue (SAS spheroids) to demonstrate concurrent operation of laser accelerator, beam shaping, dosimetry and irradiation procedure of volumetric biological samples.

3.
Phys Med Biol ; 61(8): 3084-108, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27008208

RESUMO

Preclinical in vivo studies using small animals are essential to develop new therapeutic options in radiation oncology. Of particular interest are orthotopic tumour models, which better reflect the clinical situation in terms of growth patterns and microenvironmental parameters of the tumour as well as the interplay of tumours with the surrounding normal tissues. Such orthotopic models increase the technical demands and the complexity of preclinical studies as local irradiation with therapeutically relevant doses requires image-guided target localisation and accurate beam application. Moreover, advanced imaging techniques are needed for monitoring treatment outcome. We present a novel small animal image-guided radiation therapy (SAIGRT) system, which allows for precise and accurate, conformal irradiation and x-ray imaging of small animals. High accuracy is achieved by its robust construction, the precise movement of its components and a fast high-resolution flat-panel detector. Field forming and x-ray imaging is accomplished close to the animal resulting in a small penumbra and a high image quality. Feasibility for irradiating orthotopic models has been proven using lung tumour and glioblastoma models in mice. The SAIGRT system provides a flexible, non-profit academic research platform which can be adapted to specific experimental needs and therefore enables systematic preclinical trials in multicentre research networks.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Glioblastoma/radioterapia , Neoplasias Pulmonares/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagem/métodos , Animais , Camundongos , Movimento , Imagens de Fantasmas , Ratos , Raios X
4.
Z Med Phys ; 17(3): 212-7, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-17879819

RESUMO

Positron emission tomography (PET) has become a key technology for molecular imaging in clinical practice, as well as in medical, biological and pharmaceutical research. This increases the necessity for a practical introduction to PET in students with a corresponding specialization. For this purpose, the PET scanner 'PET-TW 05' was set up to demonstrate both the principles of computer tomography (CT) as well as the basics of PET. Moreover, the technical requirements and the signal processing needed for a PET system are shown in a simplified but comprehensive way. This article illustrates the layout of the tomography and provides an overview on the signal processing, as well as on the details of data acquisition and processing. The measuring procedure is described. The results for a measurement with a simple source configuration (five 22Na sources) are also presented. Finally, the characteristic parameters and the educational goals of the tomograph are summarized.


Assuntos
Educação Médica Continuada , Tomografia por Emissão de Pósitrons , Desenho de Equipamento , Humanos , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia por Emissão de Pósitrons/métodos , Estudantes de Medicina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...