| Autor: |
Meinel, Felix G, Canstein, Christian, Schoepf, U Joseph, Sedlmaier, Martin, Schmidt, Bernhard, Harris, Brett S, Flohr, Thomas G, De Cecco, Carlo N |
| Zdroj: |
European Radiology; Jul2014, Vol. 24 Issue 7, p1643-1650, 8p |
| Abstrakt: |
Objectives: To assess the influence of tube potential on radiation dose and image quality of third-generation dual-source coronary CT angiography (CTA) in a phantom simulating an obese patient.Methods: A thoracic phantom was equipped with tubular inserts containing iodine solution and water. A soft-tissue-equivalent ring around the phantom simulated an obese patient. Images were acquired at tube potentials of 80, 100, 120 and 140 kV with second-generation dual-source CT (DSCT) and 70-150 kV (in 10-kV increments) with third-generation DSCT. Contrast-to-noise ratio (CNR) was calculated and CT dose index was recorded.Results: With second-generation DSCT, CNR was highest for 120 kV (19.0) and decreased with lower tube potential (12.0 at 80 kV) owing to disproportionately increased image noise. With third-generation DSCT, 70- and 80-kV acquisitions showed a smaller increase in noise. CNRs for third-generation DSCT were highest for 70 and 80 kV (21.1 and 21.2, respectively). Compared to 120 kV, radiation dose was 68% and 49% lower at 70 kV and 80 kV, respectively.Conclusion: Third-generation DSCT enables one to perform coronary CTA at 70-80 kV in obese patients without compromising CNR and thus reduces radiation dose by 49-68%.Key Points: • Low tube potential CT angiography is currently not suitable for obese patients. • Third-generation DSCT offers substantially increased tube power at low tube potential. • This enables one to perform coronary CT angiography at 70-80 kV in obese patients. • Signal-to-noise ratio is maintained owing to increased tube current. • This approach can be expected to reduce radiation dose by 49-68%. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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