Abstract
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.
Similar content being viewed by others
References
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 190:335–343
McCollough CH, Bruesewitz MR, Kofler JM Jr (2006) CT dose reduction and dose management tools: overview of available options. Radiographics 26:503–512
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 15:334–341
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 16:1165–1176
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 245:577–583
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 241:899–907
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 43:871–876
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 43:374–381
Livingston EH, Lee S (2001) Body surface area prediction in normal-weight and obese patients. Am J Physiol Endocrinol Metab 281:E586–E591
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 242:582–589
Huda W, Ogden KM, Khorasani MR (2008) Converting dose-length product to effective dose at CT. Radiology 248:995–1003
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 190:777–784
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 249:872–877
Bae KT, Heiken JP, Brink JA (1998) Aortic and hepatic contrast medium enhancement at CT. Part I. Prediction with a computer model. Radiology 207:647–655
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–W359
Arakawa H, Kohno T, Hiki T, Kaji Y (2007) CT pulmonary angiography and CT venography: factors associated with vessel enhancement. AJR Am J Roentgenol 189:156–161
Mettler FA Jr, Huda W, Yoshizumi TT, Mahesh M (2008) Effective doses in radiology and diagnostic nuclear medicine: a catalog. Radiology 248:254–263
Fleischmann D (2005) How to design injection protocols for multiple detector-row CT angiography (MDCTA). Eur Radiol 15 Suppl 5:E60–E65
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 43:512–519
Schaefer-Prokop C, Prokop M (2008) CTPA for the diagnosis of acute pulmonary embolism during pregnancy. Eur Radiol 18:2705–2708
U-King-Im JM, Freeman SJ, Boylan T, Cheow HK (2008) Quality of CT pulmonary angiography for suspected pulmonary embolus in pregnancy. Eur Radiol 18:2709–2715
Andreou AK, Curtin JJ, Wilde S, Clark A (2008) Does pregnancy affect vascular enhancement in patients undergoing CT pulmonary angiography? Eur Radiol 18:2716–2722
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Szucs-Farkas, Z., Strautz, T., Patak, M.A. et al. 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. Eur Radiol 19, 1914–1922 (2009). https://doi.org/10.1007/s00330-009-1385-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00330-009-1385-7