Optimization of dual-energy subtraction chest radiography by use of a direct-conversion flat-panel detector system.
Radiol Phys Technol
; 8(1): 46-52, 2015 Jan.
Article
en En
| MEDLINE
| ID: mdl-25119320
ABSTRACT
We aimed to optimize the exposure conditions in the acquisition of soft-tissue images using dual-energy subtraction chest radiography with a direct-conversion flat-panel detector system. Two separate chest images were acquired at high- and low-energy exposures with standard or thick chest phantoms. The high-energy exposure was fixed at 120 kVp with the use of an auto-exposure control technique. For the low-energy exposure, the tube voltages and entrance surface doses ranged 40-80 kVp and 20-100 % of the dose required for high-energy exposure, respectively. Further, a repetitive processing algorithm was used for reduction of the image noise generated by the subtraction process. Seven radiology technicians ranked soft-tissue images, and these results were analyzed using the normalized-rank method. Images acquired at 60 kVp were of acceptable quality regardless of the entrance surface dose and phantom size. Using a repetitive processing algorithm, the minimum acceptable doses were reduced from 75 to 40 % for the standard phantom and to 50 % for the thick phantom. We determined that the optimum low-energy exposure was 60 kVp at 50 % of the dose required for the high-energy exposure. This allowed the simultaneous acquisition of standard radiographs and soft-tissue images at 1.5 times the dose required for a standard radiograph, which is significantly lower than the values reported previously.
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Radiografía Torácica
/
Interpretación de Imagen Radiográfica Asistida por Computador
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Fantasmas de Imagen
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Nódulos Pulmonares Múltiples
Límite:
Female
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Humans
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Middle aged
Idioma:
En
Revista:
Radiol Phys Technol
Asunto de la revista:
BIOFISICA
/
RADIOLOGIA
Año:
2015
Tipo del documento:
Article