Arm raising at exposure-controlled multidetector trauma CT of thoracoabdominal region: higher image quality, lower radiation dose.
Radiology
; 249(2): 661-70, 2008 Nov.
Article
em En
| MEDLINE
| ID: mdl-18936319
ABSTRACT
PURPOSE:
To evaluate the effect of arm position on image quality and effective radiation dose in an automatic exposure-controlled (AEC) multidetector thoracoabdominal computed tomography (CT) protocol in trauma patients. MATERIALS ANDMETHODS:
This retrospective study of the data of 177 trauma patients (117 male; median age, 39 years) was approved by the institutional ethics board, with informed patient consent waived. Patients underwent scanning by using an AEC 16-detector thoracoabdominal CT protocol in which both arms were raised above the shoulder region (standard-position group, 132 patients), one arm was raised and the other was down (one-arm group, 27 patients), or both arms were down (two-arm group, 18 patients). Objective and subjective image quality was assessed. Individual effective radiation dose was calculated from the effective tube current-time product per exposed section. For this purpose, section location-dependent conversion factors were derived by using a CT dosimetry calculator. The effect of arm position on effective dose was quantified by using linear regression analysis with correction for patient volume and attenuation.RESULTS:
Compared with the image quality in the standard-position group, the image quality in the one- and two-arm groups was decreased but within acceptable diagnostic limits. The median corrected effective dose in the standard-position group was 18.6 mSv; the dose in the one-arm group was 18% (95% confidence interval 11%, 25%) higher than this, and that in the two-arm group was 45% (95% confidence interval 34%, 57%) higher.CONCLUSION:
Omitting arm raising results in lower but acceptable image quality and a substantially higher effective radiation dose. Hence, effort should be made to position the arms above the shoulder when scanning trauma patients. Clinical trial registration no. NCT00228111.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Braço
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Postura
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Ferimentos não Penetrantes
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Tomografia Computadorizada por Raios X
Tipo de estudo:
Guideline
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Observational_studies
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Prognostic_studies
Limite:
Adolescent
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Adult
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Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article