Effects of a novel tungsten-impregnated rubber neck shield on the quality of cerebral images acquired using 15O-labeled gas.
Radiol Phys Technol
; 10(4): 422-430, 2017 Dec.
Article
em En
| MEDLINE
| ID: mdl-28823084
ABSTRACT
The present study aimed to validate the effects of a novel tungsten-impregnated rubber neck shield on the quality of phantom and clinical 15O-labeled gas positron emission tomography (PET) images. Images were acquired in the presence or absence of a neck shield from a cylindrical phantom containing [15O]H2O (phantom study) and from three individuals using [15O]CO2, [15O]O2 and [15O]CO gas (clinical study). Data were acquired in three-dimensional (3D) mode using a Discovery PET/CT 710. Values for cerebral blood flow, cerebral blood volume, oxygen extraction fraction, and cerebral metabolic rate of oxygen with and without the neck shield were calculated from 15O-labeled gas images. Arterial radioactivity and count characteristics were evaluated in the phantom and clinical studies. The coefficient of variance (CV) for the phantom study and the standard deviation (SD) for functional images were also analyzed. The neck shield decreased the random count rates by 25-59% in the phantom and clinical studies. The noise equivalent count rate (NECR) increased by 44-66% in the phantom and clinical studies. Random count rates and NECR in [15O]CO2 images significantly differed with and without the neck shield. The improvement in visual and physical image quality with the neck shield was not observed in the phantom and clinical studies. The novel neck shield reduced random count rate and improved NECR in a 3D PET study using 15O-labeled gas. The image quality with the neck shield was similar to that without the neck shield.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Temas:
Agentes_cancerigenos
Base de dados:
MEDLINE
Assunto principal:
Radioisótopos de Oxigênio
/
Borracha
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Tungstênio
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Processamento de Imagem Assistida por Computador
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Encéfalo
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Imagens de Fantasmas
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Pescoço
Limite:
Humans
Idioma:
En
Revista:
Radiol Phys Technol
Assunto da revista:
BIOFISICA
/
RADIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Japão