Multidetector computed tomography pulmonary angiography: does arm position affect pulmonary artery enhancement?
J Comput Assist Tomogr
; 32(5): 778-82, 2008.
Article
em En
| MEDLINE
| ID: mdl-18830111
ABSTRACT
OBJECTIVE:
To evaluate whether arm position affects pulmonary artery enhancement in computed tomographic pulmonary angiography (CTPA).METHODS:
Study protocol had local ethics committee approval. Eighty-six patients who received 16 detector row CTPA for suspected pulmonary embolism were scanned with their contrast-injected arm resting at their side and compared with 94 patients who were scanned with both arms resting above their head. Two radiologists assessed pulmonary artery enhancement with a region-of-interest measurement of the main pulmonary artery density, scored the degree of beam-hardening artifact arising from the superior vena cava (SVC) and from the dependent arm that crossed the pulmonary arteries (1 = no artifact, 5 = artery obscured), and measured the degree of central venous compression of the injected veins at the thoracic inlet. A 2-tailed t test was performed to compare pulmonary artery density and central venous compression.RESULTS:
There was no difference in pulmonary artery enhancement between the 2 arm positions. Mean density of contrast in the main pulmonary artery was 329 Hounsfield units (HU) (95% confidence interval (CI), 310-350) in the arm-down group, compared with 325 HU (95% CI, 306-346) in the arm-up group (P = 0.65). Greater compression of the central veins occurred in the arm-up group (48.5%; 95% CI, 42.3%-54.8%) than in the arm-down group (22.3%; 95% CI, 16.8%-27.8%) (P < 0.05). There was also more beam hardening arising from contrast in the SVC in the arm-up group (P < 0.0001).CONCLUSIONS:
Arm position does not affect pulmonary arterial enhancement during CTPA. There was greater central venous compression and more beam-hardening artifact arising from the SVC when the arm was held above the head.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Braço
/
Artéria Pulmonar
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Tomografia Computadorizada por Raios X
Tipo de estudo:
Etiology_studies
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Incidence_studies
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Observational_studies
/
Risk_factors_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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Middle aged
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article