Quantitative multi-detector emission computerized tomography using iterative attenuation compensation.
J Nucl Med
; 23(8): 706-14, 1982 Aug.
Article
em En
| MEDLINE
| ID: mdl-6980972
ABSTRACT
An iterative procedure to correct for attenuation has been developed for a multidetector, single-photon emission tomographic scanner. The difference between measured and estimated data projections is used at each iteration to form an error image which is used, in turn, to correct the image. A damping factor that minimizes chi2 is applied after each iteration to speed convergence. Several phantoms of different size, with various concentration distributions, have been used to compare this method with a first-order multiplicative attenuation correction used previously with this scanner. The first-order correction is inadequate for most of the phantoms studied, whereas relative and absolute quantitative capability is demonstrated for the iterative attenuation correction. The reconstructed average number of counts per pixel is a linear function of activity concentration up to 5 muCi/ml for all regions of uniform activity whose size is greater than or equal to 5 cm. The importance of using an accurate attenuation distribution with this method is demonstrated with a torso-like phantom.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tomografia Computadorizada de Emissão
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Nucl Med
Ano de publicação:
1982
Tipo de documento:
Article