European Radiology

, Volume 19, Issue 8, pp 1914–1922 | Cite as

Is body weight the most appropriate criterion to select patients eligible for low-dose pulmonary CT angiography? Analysis of objective and subjective image quality at 80 kVp in 100 patients

  • Zsolt Szucs-Farkas
  • Tamara Strautz
  • Michael A. PatakEmail author
  • Luzia Kurmann
  • Peter Vock
  • Sebastian T. Schindera


The objective of this retrospective study was to assess image quality with pulmonary CT angiography (CTA) using 80 kVp and to find anthropomorphic parameters other than body weight (BW) to serve as selection criteria for low-dose CTA. Attenuation in the pulmonary arteries, anteroposterior and lateral diameters, cross-sectional area and soft-tissue thickness of the chest were measured in 100 consecutive patients weighing less than 100 kg with 80 kVp pulmonary CTA. Body surface area (BSA) and contrast-to-noise ratios (CNR) were calculated. Three radiologists analyzed arterial enhancement, noise, and image quality. Image parameters between patients grouped by BW (group 1: 0–50 kg; groups 2–6: 51–100 kg, decadally increasing) were compared. CNR was higher in patients weighing less than 60 kg than in the BW groups 71–99 kg (P between 0.025 and <0.001). Subjective ranking of enhancement (P = 0.165–0.605), noise (P = 0.063), and image quality (P = 0.079) did not differ significantly across all patient groups. CNR correlated moderately strongly with weight (R = −0.585), BSA (R = −0.582), cross-sectional area (R = −0.544), and anteroposterior diameter of the chest (R = −0.457; P < 0.001 all parameters). We conclude that 80 kVp pulmonary CTA permits diagnostic image quality in patients weighing up to 100 kg. Body weight is a suitable criterion to select patients for low-dose pulmonary CTA.


Pulmonary CT angiography Radiation exposure Image quality 


  1. 1.
    Kubo T, Lin PJ, Stiller W, Takahashi M, Kauczor HU, Ohno Y, Hatabu H (2008) Radiation dose reduction in chest CT: a review. AJR Am J Roentgenol 190:335–343PubMedCrossRefGoogle Scholar
  2. 2.
    McCollough CH, Bruesewitz MR, Kofler JM Jr (2006) CT dose reduction and dose management tools: overview of available options. Radiographics 26:503–512PubMedCrossRefGoogle Scholar
  3. 3.
    Wintersperger B, Jakobs T, Herzog P, Schaller S, Nikolaou K, Suess C, Weber C, Reiser M, Becker C (2005) Aorto-iliac multidetector-row CT angiography with low kV settings: improved vessel enhancement and simultaneous reduction of radiation dose. Eur Radiol 15:334–341PubMedCrossRefGoogle Scholar
  4. 4.
    Holmquist F, Nyman U (2006) Eighty-peak kilovoltage 16-channel multidetector computed tomography and reduced contrast-medium doses tailored to body weight to diagnose pulmonary embolism in azotaemic patients. Eur Radiol 16:1165–1176PubMedCrossRefGoogle Scholar
  5. 5.
    Heyer CM, Mohr PS, Lemburg SP, Peters SA, Nicolas V (2007) Image quality and radiation exposure at pulmonary CT angiography with 100- or 120-kVp protocol: prospective randomized study. Radiology 245:577–583PubMedCrossRefGoogle Scholar
  6. 6.
    Schueller-Weidekamm C, Schaefer-Prokop CM, Weber M, Herold CJ, Prokop M (2006) CT angiography of pulmonary arteries to detect pulmonary embolism: improvement of vascular enhancement with low kilovoltage settings. Radiology 241:899–907PubMedCrossRefGoogle Scholar
  7. 7.
    Szucs-Farkas Z, Kurmann L, Strautz T, Patak MA, Vock P, Schindera ST (2008) Patient exposure and image quality of low-dose pulmonary computed tomography angiography: comparison of 100- and 80-kVp protocols. Invest Radiol 43:871–876PubMedCrossRefGoogle Scholar
  8. 8.
    Szucs-Farkas Z, Verdun FR, von Allmen G, Mini RL, Vock P (2008) Effect of X-ray tube parameters, iodine concentration, and patient size on image quality in pulmonary computed tomography angiography: a chest-phantom-study. Invest Radiol 43:374–381PubMedCrossRefGoogle Scholar
  9. 9.
    Livingston EH, Lee S (2001) Body surface area prediction in normal-weight and obese patients. Am J Physiol Endocrinol Metab 281:E586–E591PubMedGoogle Scholar
  10. 10.
    Bae KT, Tao C, Gurel S, Hong C, Zhu F, Gebke TA, Milite M, Hildebolt CF (2007) Effect of patient weight and scanning duration on contrast enhancement during pulmonary multidetector CT angiography. Radiology 242:582–589PubMedCrossRefGoogle Scholar
  11. 11.
    Huda W, Ogden KM, Khorasani MR (2008) Converting dose-length product to effective dose at CT. Radiology 248:995–1003PubMedCrossRefGoogle Scholar
  12. 12.
    Bae KT, Seeck BA, Hildebolt CF, Tao C, Zhu F, Kanematsu M, Woodard PK (2008) Contrast enhancement in cardiovascular MDCT: effect of body weight, height, body surface area, body mass index, and obesity. AJR Am J Roentgenol 190:777–784PubMedCrossRefGoogle Scholar
  13. 13.
    Kondo H, Kanematsu M, Goshima S, Tomita Y, Miyoshi T, Hatcho A, Moriyama N, Onozuka M, Shiratori Y, Bae KT (2008) Abdominal multidetector CT in patients with varying body fat percentages: estimation of optimal contrast material dose. Radiology 249:872–877PubMedCrossRefGoogle Scholar
  14. 14.
    Bae KT, Heiken JP, Brink JA (1998) Aortic and hepatic contrast medium enhancement at CT. Part I. Prediction with a computer model. Radiology 207:647–655PubMedGoogle Scholar
  15. 15.
    Roggenland D, Peters SA, Lemburg SP, Holland-Letz T, Nicolas V, Heyer CM (2008) CT angiography in suspected pulmonary embolism: impact of patient characteristics and different venous lines on vessel enhancement and image quality. AJR Am J Roentgenol 190:W351–W359PubMedCrossRefGoogle Scholar
  16. 16.
    Arakawa H, Kohno T, Hiki T, Kaji Y (2007) CT pulmonary angiography and CT venography: factors associated with vessel enhancement. AJR Am J Roentgenol 189:156–161PubMedCrossRefGoogle Scholar
  17. 17.
    Mettler FA Jr, Huda W, Yoshizumi TT, Mahesh M (2008) Effective doses in radiology and diagnostic nuclear medicine: a catalog. Radiology 248:254–263PubMedCrossRefGoogle Scholar
  18. 18.
    Fleischmann D (2005) How to design injection protocols for multiple detector-row CT angiography (MDCTA). Eur Radiol 15 Suppl 5:E60–E65CrossRefGoogle Scholar
  19. 19.
    Nakaura T, Awai K, Yauaga Y, Nakayama Y, Oda S, Hatemura M, Nagayoshi Y, Ogawa H, Yamashita Y (2008) Contrast injection protocols for coronary computed tomography angiography using a 64-detector scanner: comparison between patient weight-adjusted- and fixed iodine-dose protocols. Invest Radiol 43:512–519PubMedCrossRefGoogle Scholar
  20. 20.
    Schaefer-Prokop C, Prokop M (2008) CTPA for the diagnosis of acute pulmonary embolism during pregnancy. Eur Radiol 18:2705–2708PubMedCrossRefGoogle Scholar
  21. 21.
    U-King-Im JM, Freeman SJ, Boylan T, Cheow HK (2008) Quality of CT pulmonary angiography for suspected pulmonary embolus in pregnancy. Eur Radiol 18:2709–2715PubMedCrossRefGoogle Scholar
  22. 22.
    Andreou AK, Curtin JJ, Wilde S, Clark A (2008) Does pregnancy affect vascular enhancement in patients undergoing CT pulmonary angiography? Eur Radiol 18:2716–2722PubMedCrossRefGoogle Scholar

Copyright information

© European Society of Radiology 2009

Authors and Affiliations

  • Zsolt Szucs-Farkas
    • 1
  • Tamara Strautz
    • 1
  • Michael A. Patak
    • 1
    Email author
  • Luzia Kurmann
    • 1
  • Peter Vock
    • 1
  • Sebastian T. Schindera
    • 1
  1. 1.Department of Diagnostic, Interventional and Paediatric RadiologyUniversity Hospital and University of BerneBerneSwitzerland

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