Image quality and radiation dose of lower extremity CT angiography at 70 kVp on an integrated circuit detector dual-source computed tomography

• Published in: Acta radiologica (1987) 2015-06, Vol.56 (6), p.659-665
• Main Authors: Qi, Li, Zhao, Yan’E, Zhou, Chang Sheng, Spearman, James V, Renker, Matthias, Schoepf, U Joseph, Zhang, Long Jiang, Lu, Guang Ming
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Angiography - methods; Feasibility Studies; Female; Humans; Lower Extremity - blood supply; Lower Extremity - diagnostic imaging; Male; Middle Aged; Radiation Dosage; Retrospective Studies; Tomography, X-Ray Computed - methods; Young Adult
• ISSN: 0284-1851; 1600-0455
• DOI: 10.1177/0284185114535391

Background Despite the well-established requirement for radiation dose reduction there are few studies examining the potential for lower extremity CT angiography (CTA) at 70 kVp. Purpose To compare the image quality and radiation dose of lower extremity CTA at 70 kVp using a dual-source CT system with an integrated circuit detector to similar studies at 120 kVp. Material and Methods A total of 62 patients underwent lower extremity CTA. Thirty-one patients were examined at 70 kVp using a second generation dual-source CT with an integrated circuit detector (70 kVp group) and 31 patients were evaluated at 120 kVp using a first generation dual-source CT (120 kVp group). The attenuation and image noise were measured and signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Two radiologists assessed image quality. Radiation dose was compared. Results The mean attenuation of the 70 kVp group was higher than the 120 kVp group (575 ± 149 Hounsfield units [HU] vs. 258 ± 38 HU, respectively, P