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CT angiography for pulmonary embolism in the emergency department: investigation of a protocol by 20 ml of high-concentration contrast medium

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To retrospectively compare semi-qualitative and quantitative CT pulmonary angiography (CTPAs) image metrics testing diagnostic performance between protocols performed by 20 or 40 ml of contrast medium (CM) in patients with suspected pulmonary embolism (PE).


A total of 102 CTPAs performed by 20 ml (ultra-low volume: ULV) and 74 CTPAs performed by 40 ml (low volume: LV) protocol for the diagnosis of clinically suspected PE performed between October 2012 and September 2013 were retrieved. High-concentration CM (Iomeprol 400 mgI/ml) was injected at 3 ml/s (iodine delivery rate 1.2 mgI/s). Two radiologists (blinded and independent) semi-qualitatively scored vascular enhancement and image noise according to a five-point visual scoring system. Quantitative analysis was performed by regions of interest quantifying densitometric parameters, such as central and peripheral pulmonary arteries vascular contrast enhancement (CE, threshold for diagnostic CE ≥ 250 HU), and metrics for image noise. Continuous variables were compared by the Student’s t test between groups if normally distributed while categorical variables were analyzed with the Chi-squared test. Interobserver agreement was calculated by the weighted kappa test; correlation coefficients were calculated using Pearson’s correlation tests.


The semi-qualitative scores for central and peripheral pulmonary arteries vascular CE were sufficient by ULV, yet inferior than LV (p < 0.001). Semi-qualitative image noise was comparable between ULV and LV, and the interobserver agreement was only fair for quality of peripheral vessels. Agreement on nondiagnostic semi-qualitative parameters was seen in 9/102 (8.8%) ULV CTPAs, in particular associated with massive PE (2/9), pleuro-pulmonary abnormalities (5/9) or without major abnormalities (2/9). Quantitative analysis showed that mean CE was lower in ULV group (p < 0.001), though greater than the diagnostic threshold of 250 HU in both groups.


Diagnostic vascular CE (> 250 HU) was obtained in both 20 ml and 40 ml CTPAs. CTPA by 20 ml of CM rendered diagnostic CE for the assessment of pulmonary arteries in patients with clinical suspicion of acute PE. Decreased image quality was mostly associated with massive PE or concomitant pleuro-parenchymal abnormalities.

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  1. Konstantinides SV, Torbicki A, Agnelli G, Danchin N, Fitzmaurice D, Galie N, Gibbs JS, Huisman MV, Humbert M, Kucher N, Lang I, Lankeit M, Lekakis J, Maack C, Mayer E, Meneveau N, Perrier A, Pruszczyk P, Rasmussen LH, Schindler TH, Svitil P, Vonk Noordegraaf A, Zamorano JL, Zompatori M, Task Force for the D, Management of Acute Pulmonary Embolism of the European Society of C (2014) 2014 ESC guidelines on the diagnosis and management of acute pulmonary embolism. Eur Heart J 35(43):3033–3069.

    Article  CAS  PubMed  Google Scholar 

  2. Heit JA, Spencer FA, White RH (2016) The epidemiology of venous thromboembolism. J Thromb Thrombolysis 41(1):3–14.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  3. Remy-Jardin M, Pistolesi M, Goodman LR, Gefter WB, Gottschalk A, Mayo JR, Sostman HD (2007) Management of suspected acute pulmonary embolism in the era of CT angiography: a statement from the Fleischner society. Radiology 245(2):315–329.

    Article  PubMed  Google Scholar 

  4. Turedi S, Erdem E, Karaca Y, Tatli O, Sahin A, Turkmen S, Gunduz A (2016) The high risk of contrast-induced nephropathy in patients with suspected pulmonary embolism despite three different prophylaxis: a randomized controlled trial. Acad Emerg Med 23(10):1136–1145.

    Article  PubMed  Google Scholar 

  5. Tao SM, Wichmann JL, Schoepf UJ, Fuller SR, Lu GM, Zhang LJ (2016) Contrast-induced nephropathy in CT: incidence, risk factors and strategies for prevention. Eur Radiol 26(9):3310–3318.

    Article  PubMed  Google Scholar 

  6. Stacul F, van der Molen AJ, Reimer P, Webb JA, Thomsen HS, Morcos SK, Almen T, Aspelin P, Bellin MF, Clement O, Heinz-Peer G, Contrast Media Safety Committee of European Society of Urogenital R (2011) Contrast induced nephropathy: updated ESUR Contrast Media Safety Committee guidelines. Eur Radiol 21(12):2527–2541.

    Article  PubMed  Google Scholar 

  7. Beckett KR, Moriarity AK, Langer JM (2015) Safe use of contrast media: what the radiologist needs to know. Radiographics 35(6):1738–1750.

    Article  PubMed  Google Scholar 

  8. van der Molen AJ, Reimer P, Dekkers IA, Bongartz G, Bellin MF, Bertolotto M, Clement O, Heinz-Peer G, Stacul F, Webb JAW, Thomsen HS (2018) Post-contrast acute kidney injury—part 1: definition, clinical features, incidence, role of contrast medium and risk factors: Recommendations for updated ESUR Contrast Medium Safety Committee guidelines. Eur Radiol 28(7):2845–2855.

    Article  PubMed  PubMed Central  Google Scholar 

  9. Szucs-Farkas Z, Christe A, Megyeri B, Rohacek M, Vock P, Nagy EV, Heverhagen JT, Schindera ST (2014) Diagnostic accuracy of computed tomography pulmonary angiography with reduced radiation and contrast material dose: a prospective randomized clinical trial. Invest Radiol 49(4):201–208.

    Article  CAS  PubMed  Google Scholar 

  10. Faggioni L, Neri E, Sbragia P, Pascale R, D’Errico L, Caramella D, Bartolozzi C (2012) 80-kV pulmonary CT angiography with 40 mL of iodinated contrast material in lean patients: comparison of vascular enhancement with iodixanol (320 mg I/mL)and iomeprol (400 mg I/mL). AJR Am J Roentgenol 199(6):1220–1225.

    Article  PubMed  Google Scholar 

  11. Wu CC, Lee EW, Suh RD, Levine BS, Barack BM (2012) Pulmonary 64-MDCT angiography with 30 mL of IV contrast material: vascular enhancement and image quality. AJR Am J Roentgenol 199(6):1247–1251.

    Article  PubMed  Google Scholar 

  12. Delesalle MA, Pontana F, Duhamel A, Faivre JB, Flohr T, Tacelli N, Remy J, Remy-Jardin M (2013) Spectral optimization of chest CT angiography with reduced iodine load: experience in 80 patients evaluated with dual-source, dual-energy CT. Radiology 267(1):256–266.

    Article  PubMed  Google Scholar 

  13. Saade C, Bourne R, El-Merhi F, Somanathan A, Chakraborty D, Brennan P (2013) An optimised patient-specific approach to administration of contrast agent for CT pulmonary angiography. Eur Radiol 23(11):3205–3212.

    Article  PubMed  Google Scholar 

  14. Hendriks BM, Kok M, Mihl C, Bekkers SC, Wildberger JE, Das M (2016) Individually tailored contrast enhancement in CT pulmonary angiography. Br J Radiol 89(1061):20150850.

    Article  PubMed  PubMed Central  Google Scholar 

  15. Lu GM, Luo S, Meinel FG, McQuiston AD, Zhou CS, Kong X, Zhao YE, Zheng L, Schoepf UJ, Zhang LJ (2014) High-pitch computed tomography pulmonary angiography with iterative reconstruction at 80 kVp and 20 mL contrast agent volume. Eur Radiol 24(12):3260–3268.

    Article  PubMed  Google Scholar 

  16. Horehledova B, Mihl C, Milanese G, Brans R, Eijsvoogel NG, Hendriks BMF, Wildberger JE, Das M (2018) CT angiography in the lower extremity peripheral artery disease feasibility of an ultra-low volume contrast media protocol. Cardiovasc Interv Radiol 41(11):1751–1764.

    Article  Google Scholar 

  17. Aschoff AJ, Catalano C, Kirchin MA, Krix M, Albrecht T (2017) Low radiation dose in computed tomography: the role of iodine. Br J Radiol 90(1076):20170079.

    Article  PubMed  PubMed Central  Google Scholar 

  18. Hendriks BMF, Schnerr RS, Milanese G, Jeukens C, Niesen S, Eijsvoogel NG, Wildberger JE, Das M (2019) Computed tomography pulmonary angiography during pregnancy: radiation dose of commonly used protocols and the effect of scan length optimization. Korean J Radiol 20(2):313–322.

    Article  PubMed  Google Scholar 

  19. Boos J, Kropil P, Lanzman RS, Aissa J, Schleich C, Heusch P, Sawicki LM, Antoch G, Thomas C (2016) CT pulmonary angiography: simultaneous low-pitch dual-source acquisition mode with 70 kVp and 40 ml of contrast medium and comparison with high-pitch spiral dual-source acquisition with automated tube potential selection. Br J Radiol 89(1062):20151059.

    Article  PubMed  PubMed Central  Google Scholar 

  20. Wittram C, Maher MM, Yoo AJ, Kalra MK, Shepard JA, McLoud TC (2004) CT angiography of pulmonary embolism: diagnostic criteria and causes of misdiagnosis. Radiographics 24(5):1219–1238.

    Article  PubMed  Google Scholar 

  21. Godoy MC, Heller SL, Naidich DP, Assadourian B, Leidecker C, Schmidt B, Vlahos I (2011) Dual-energy MDCT: comparison of pulmonary artery enhancement on dedicated CT pulmonary angiography, routine and low contrast volume studies. Eur J Radiol 79(2):e11–e17.

    Article  PubMed  Google Scholar 

  22. 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(2):582–589.

    Article  PubMed  Google Scholar 

  23. Horehledova B, Mihl C, Milanese G, Brans R, Eijsvoogel NG, Hendriks BMF, Wildberger JE, Das M (2018) CT Angiography in the lower extremity peripheral artery disease feasibility of an ultra-low volume contrast media protocol. Cardiovasc Interv Radiol.

    Article  Google Scholar 

  24. Watson PF, Petrie A (2010) Method agreement analysis: a review of correct methodology. Theriogenology 73(9):1167–1179.

    Article  CAS  PubMed  Google Scholar 

  25. Hemmett J, Er L, Chiu HH, Cheung C, Djurdjev O, Levin A (2015) Time to revisit the problem of CIN? The low incidence of acute kidney injury with and without contrast in hospitalized patients: an observational cohort study. Can J Kidney Health Dis 2:38.

    Article  PubMed  PubMed Central  Google Scholar 

  26. McDonald JS, McDonald RJ, Carter RE, Katzberg RW, Kallmes DF, Williamson EE (2014) Risk of intravenous contrast material-mediated acute kidney injury: a propensity score-matched study stratified by baseline-estimated glomerular filtration rate. Radiology 271(1):65–73.

    Article  PubMed  Google Scholar 

  27. Radon MR, Kaduthodil MJ, Jagdish J, Matthews S, Hill C, Bull MJ, Morcos SK (2011) Potentials and limitations of low-concentration contrast medium (150 mg iodine/ml) in CT pulmonary angiography. Clin Radiol 66(1):43–49.

    Article  CAS  PubMed  Google Scholar 

  28. Iezzi R, Santoro M, Marano R, Di Stasi C, Dattesi R, Kirchin M, Tinelli G, Snider F, Bonomo L (2012) Low-dose multidetector CT angiography in the evaluation of infrarenal aorta and peripheral arterial occlusive disease. Radiology 263(1):287–298.

    Article  PubMed  Google Scholar 

  29. Faggioni L, Gabelloni M (2016) Iodine concentration and optimization in computed tomography angiography: current issues. Invest Radiol 51(12):816–822.

    Article  CAS  PubMed  Google Scholar 

  30. Costantino G, Norsa AH, Amadori R, Ippolito S, Resta F, Bianco R, Casazza G, Biagiotti S, Rusconi AM, Montano N (2009) Interobserver agreement in the interpretation of computed tomography in acute pulmonary embolism. Am J Emerg Med 27(9):1109–1111.

    Article  PubMed  Google Scholar 

  31. Trattner S, Pearson GDN, Chin C, Cody DD, Gupta R, Hess CP, Kalra MK, Kofler JM Jr, Krishnam MS, Einstein AJ (2014) Standardization and optimization of CT protocols to achieve low dose. J Am Coll Radiol 11(3):271–278.

    Article  PubMed  PubMed Central  Google Scholar 

  32. Martini K, Barth BK, Nguyen-Kim TD, Baumueller S, Alkadhi H, Frauenfelder T (2016) Evaluation of pulmonary nodules and infection on chest CT with radiation dose equivalent to chest radiography: prospective intra-individual comparison study to standard dose CT. Eur J Radiol 85(2):360–365.

    Article  CAS  PubMed  Google Scholar 

  33. Milanese G, Silva M, Frauenfelder T, Eberhard M, Sabia F, Martini C, Marchiano A, Prokop M, Sverzellati N, Pastorino U (2019) Comparison of ultra-low dose chest CT scanning protocols for the detection of pulmonary nodules: a phantom study. Tumori.

    Article  PubMed  Google Scholar 

  34. Mayo J, Thakur Y (2013) Pulmonary CT angiography as first-line imaging for PE: image quality and radiation dose considerations. AJR Am J Roentgenol 200(3):522–528.

    Article  PubMed  Google Scholar 

  35. Hendriks BMF, Eijsvoogel NG, Kok M, Martens B, Wildberger JE, Das M (2018) Optimizing pulmonary embolism computed tomography in the age of individualized medicine: a prospective clinical study. Invest Radiol.

    Article  PubMed  Google Scholar 

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Correspondence to Mario Silva.

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Silva, M., Milanese, G., Cobelli, R. et al. CT angiography for pulmonary embolism in the emergency department: investigation of a protocol by 20 ml of high-concentration contrast medium. Radiol med 125, 137–144 (2020).

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