Seventy-Peak Kilovoltage High-Pitch Thoracic Aortic CT Angiography without ECG Gating: Evaluation of Image Quality and Radiation Dose.
Acad Radiol
; 22(7): 890-7, 2015 Jul.
Article
em En
| MEDLINE
| ID: mdl-25872860
ABSTRACT
RATIONALE AND OBJECTIVES:
To assess the feasibility of 70-kVp high-pitch non-ECG-gated thoracic aortic computed tomography angiography (CTA) with 40-mL contrast agent compared to 100-kVp standard-pitch CTA with 60-mL contrast agent. MATERIALS ANDMETHODS:
Sixty-seven patients (51 men and 16 women; mean age, 55 ± 14 years) received non-ECG-gated aortic CTA at 70 kVp, high pitch of 3.4, and 40-mL contrast agent (group A, n = 31) or CTA at 100-kVp, pitch of 1.2, and 60-mL contrast agent (group B, n = 36). Iterative reconstruction was used in all patients. For image quality assessment, CTA images were evaluated on a three-point scale and signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated and compared. Furthermore, computed tomography (CT) dose index was recorded.RESULTS:
Mean CT values and noise levels were higher in group A compared to group B (all P < .001), whereas SNR and CNR were lower than those in group B (all P < .001). Furthermore, the image quality of the aorta at the level of the diaphragm was lower in group A than that in group B (P < .05). However, image quality was graded as diagnostic in all patients, and motion artifacts of the aortic arch were significantly decreased in group A (P <.05). Interreader agreement was good or excellent for image quality assessment (k = 0.625-0.835). The 70-kVp CTA protocol, which allows dose reduction of 85%, was considered diagnostic in all instances by two readers.CONCLUSIONS:
Our proposed thoracic aortic CTA protocol provides diagnostic information with substantial reduction of both radiation and contrast agent doses compared to standard-pitch CTA at 100 kVp.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Aorta Torácica
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Doenças da Aorta
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Doses de Radiação
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Aortografia
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Interpretação de Imagem Assistida por Computador
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Tomografia Computadorizada por Raios X
Tipo de estudo:
Diagnostic_studies
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Guideline
Limite:
Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Acad Radiol
Ano de publicação:
2015
Tipo de documento:
Article